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CA chiti (cyclohexanone le cyclohexanol cawhmi) in adipic acid (nylon 66 a chuahtertu) electrosynthesis cu a hmunmi strategy a si i a harmi thil sining a herhmi hlanlio lam hna kha a thlen khawh. Sihmanhsehlaw, a tlawmmi current density le aa zuammi oxygen thlennak nih a riantuannak hmannak kha a tlawmter ngaingai. Hi rian ah, nickel double hydroxide cu vanadium he kan remh i a tu lio a ritmi le a sangmi faradaic tthatnak (>80%) kha a kau ngaimi potential range (1.5–1.9 V vs. reversible hydrogen electrode) cung ah kan kilven. Hneksaknak le ruahnak hlathlainak nih V remhnak ah a biapi bikmi rian pahnih a langhter, cu hna ah cun a rangmi catalyst remhthannak le a tthanchomi cyclohexanone laknak hna aa tel. Ruahnak tehte ah, kannih nih membrane-electrode fonhmi kan ser i cu nih cun adipic acid cu a sangmi faradaic tthatnak (82%) le chuah khawhnak (1536 μmol cm-2 h-1) he riantuannak he aa pehtlaimi current density (300 mA cm-2) ah a chuahter, cu lio ah fekmi >50 h a hmuh. Hi rian nih hin adipic acid electrosynthesis caah a ttha ngaimi thilchuah khawhnak le riantuannak ah a tthatnak a langhter.
Adipic acid (AA) cu a biapi bikmi aliphatic dicarboxylic acid pakhat a si i nylon 66 le a dang polyamides asiloah polymers1 sernak ah hman a si bik. Chawlehnak ah, AA cu cyclohexanol le cyclohexanone (cucu, AA chiti) cawhmi kha 50-60 vol% nitric acid hmangin oxidizing tuahnak in sermi a si. Hi thil kalning nih hin pawngkam kongah lungretheihnak a ngei i, nitric acid le nitrogen oxides (N2O le NOx) kha greenhouse gas bantuk in chuahternak he aa pehtlaimi a si2,3. H2O2 cu a dang green oxidizing agent ah hman khawh a si ko nain, a man a fakmi le a harmi sernak dirhmun nih hman khawh a harter, cun a man a fawi deuhmi le a hmunmi lam a herh4,5,6.
A luancia kum hra chung ah, electrocatalytic chemical le meihol sernak lam hna nih scientist pawl lungthin a lak chin lengmang hna, zeicahtiah an tthatnak cu thlen khawhmi thazaang hmannak le a nemmi thil sining (tahchunhnak ah, khaan lum le pawngkam thli) tangah riantuannak ah a si.7,8,9,10. Hi kong he pehtlai in, KA chiti kha AA ah electrocatalytic thlennak sernak cu a cunglei ṭhatnak hmuh khawhnak ding caah a biapi tuk i cu pin ah phungning tein chuahmi ah tonmi nitric acid le nitrous oxide chuahnak hmannak hloh khawhnak ding caah a biapi tuk (Figure 1a). Petrosyan et al. nih a hmasa bik rian an ttuan, annih nih nickel oxyhydroxide (NiOOH) cung ah cyclohexanone (COR; cyclohexanone asiloah cyclohexanol cu ​​KA chiti aiawh in hlathlainak tuah a si tawn) i electrocatalytic oxidation reaction kong an thanh, asinain a tlawmmi current density (6 cm) le a tlawm deuhmi A-A (25%) an chuah hmuhmi11,12. Cu hnu cun, COR cawlcanghnak thanchoternak caah nickel-based catalysts sernak ah tthanchonak nganpi a um. Tahchunhnak ah, cyclohexanol13 ah Cα–Cβ tthennak thanchoternak caah dar-doped nickel hydroxide (Cu-Ni(OH)2) catalyst cu ser a si. Nai ah khan Ni(OH)2 catalyst cu sodium dodecyl sulfonate (SDS) he remhmi a si i cyclohexanone14 a tthanchotermi ti a doh khomi pawngkam a ser.
a KA chiti electrooxidation in AA chuah khawhnak harnak hna. b A hlan ah report tuahmi Ni-based catalysts le kan catalyst hna i electrode pathum system le flow battery system ah electrocatalytic COR tahchunhnak11,13,14,16,26. Reaction parameters le reaction riantuan ning kong he pehtlai in a tlingmi thawngpang cu Supplementary Tables 1 le 2 ah pek a si. c H-cell reactor le MEA ah COR caah kan NiV-LDH-NS catalysts hna i catalytic riantuan ning, cu hna cu a kau ngaimi thil ti khawhnak hmun ah rian an ttuan.
A cunglei lam hna nih COR cawlcanghnak kha a tthanchoter ko nain, langhtermi Ni-based catalysts nih AA Faraday tthatnak (FE) (>80%) sang kha a niam deuhmi thilti khawhnak lawng ah an langhter, a tlangpi in 1.6 V tang ah a kir khomi hydrogen electrode (RHE, a tawinak in VRHE) he tahchunh tikah. Cucaah, AA i report tuahmi a cheuchum tthawnnak (cucu, FE in karhtermi tthawnnak dihlak) cu 60 mA cm−2 tang ah a um zungzal (Figure 1b le Supplementary Table 1). A tlawmmi current density cu riantuannak nih a herhmi (>200 mA cm−2)15 nak in a niam deuh ngai, cu nih cun a sangmi AA sernak caah electrocatalytic thiamnak kha a kham ngaingai (Figure 1a; cunglei). Current density karhternak caah, a ttha deuhmi potential (electrode pathum system caah) asiloah a sang deuhmi cell voltage (electrode pahnih system caah) hman khawh a si, cucu electrocatalytic thlennak tampi caah a sawhsawh mi lam a si, a hlei in oxygen evolution reaction (OER). Sihmanhsehlaw, anodic thazaang sang ah COR caah, OER cu AA FE zorternak ah zuamnak nganpi ah a cang kho, cucaah thazaang tthatnak a zorter (Figure 1a; tanglei). Tahchunhnak ah, a hlan i tthanchonak (Figure 1b le Supplementary Table 1) zoh tikah, SDS-modified Ni(OH)2 cung i AA FE cu 1.5 VRHE in 1.7 VRHE14 tiang hmanmi thilti khawhnak karhternak he 93% in 76% tiang a zor ti kan hmuh tikah kan lung a dong, cu lio ah AA FE cu 1.5 VRHE in 1.7 VRHE14 tiang a zor 93% in 69% tiang 1.52 VRHE in 1.62 VRHE16 tiang a tthancho khawhnak he. Cucaah, report tuahmi AA i a cheuchum current density cu a sang deuhmi potential ah aa tluk tein a karh lo, cu nih cun AA riantuan ning tthanchonak kha a tlawmter, AA FE a niam ruangah thazaang hmannak a sangmi chim loin. Nickel-based catalysts pin ah, cobalt-based catalysts zong nih COR17,18,19 ah catalytic cawlcanghnak an langhter. Sihmanhsehlaw, an tthatnak cu a sang deuhmi thilti khawhnak ah a zor, cun Ni-based catalysts he tahchunh ahcun, annih cu chawlehnak hmannak ah thilti khawhnak rikhiahnak tam deuh an ngei, cu hna cu man thlennak ngan deuh le thilri chiahnak hme deuh tibantuk an si. Cucaah, AA chuah khawhnak sang hmuh khawhnak ding caah COR ah a sangmi current density le FE he Ni-based catalysts ser cu duhnung a si.
Hi rian ah, vanadium(V)-modified nickel layered double hydroxide nanosheets (NiV-LDH-NS) cu COR hmangin AA chuah khawhnak caah a ttha ngaimi electrocatalysts ah kan langhter, cu hna cu a kau ngaimi potential range cung ah a ttha tukmi OER he rian an ttuan, H-cells le membrane electrodes fonhmi pahnih ah FE sang le current density an hmuh (Figure 1AME; AME hmanthlak 1). A hmasa bik ah kan langhter mi cu a tlangpi in Ni(OH)2 nanosheet catalyst (Ni(OH)2-NS) cung i acetylene oxidation tthatnak cu a zor, ruahchannak bantuk in, a sang deuhmi thilti khawhnak ah, 1.5 VRHE ah 80% in 1.9 VRHE ah 42% tiang. A dang tein, Ni(OH)2 kha V he remh hnu ah, NiV-LDH-NS nih a pekmi thilti khawhnak ah a sang deuhmi tthawnnak a langhter i, a biapi deuhmi cu, a kau ngaimi thilti khawhnak hmun ah FE sang deuh a ngeih. Tahchunhnak ah, 1.9 VRHE ah, 170 mA cm−2 le 83% FE a langhter, cucu three-electrode system ah COR caah a ttha deuhmi catalyst a si (Fig. 1c le Supplementary Table 1). Hneksaknak le ruahnak data nih a langhter mi cu V remhnak nih Ni(OH)2 in a sangmi Ni oxyhydroxides (Ni3+xOOH1-x) ah tlawmternak kinetics a thanchoter, cu hna cu COR caah a cawlcangmi dirhmun ah an ṭuan. Cun, V remhnak nih catalyst cunglei ah cyclohexanone laknak kha a ṭhanchoter, cucu anodic ṭhawnnak sang ah OER khamnak ah a biapi tukmi rian a ṭuan. NiV-LDH-NS thilti khawhnak kha a tak deuhmi thil sining ah langhter awkah, MEA luannak reactor kan suai i AA (82%) FE kha riantuannak he aa pehtlaimi current density (300 mA cm−2) ah kan langhter, cucu membrane luannak reactor ah kan hmuhmi nakin a sang deuh ngaingai (Fig. 1b le Supplementary Table 2). AA (1536 μmol cm−2 h−1) he aa tlakmi chuahmi cu lumternak thlennak (<30 mmol gcatalyst−1 h−1)4 hmangin hmuhmi nakin a sang deuh. Cun, MEA hman tikah catalyst nih a fekmi dirhmun a langhter, 200 mA cm−2 ah 60 h chung FE >80% AA le 300 mA cm−2 ah 58 h chung FE >70% AA a chiah. A donghnak ah, a hmasa bik tuah khawhnak hlathlainak (FEA) nih AA chuah khawhnak caah electrocatalytic strategy man a tthatnak kha a langhter.
A hlan cauk ning in, Ni(OH)2 cu COR caah cawlcanghnak ttha a langhtermi a tlangpi in thlennak a si, cucaah Ni(OH)2-NS13,14 cu a voikhatnak caah coprecipitation phunglam in sermi a si. Sample pawl nih β-Ni(OH)2 sining an langhter, cucu X-ray diffraction (XRD; Fig. 2a) in fehter a si, cun a tlawm tukmi nanosheets (a thuhnak: 2–3 nm, a kam a ngan: 20–50 nm) cu high-resolution transmission electron microscopy (HRTEM Supplementary Fig. 1) le microscopy caah hmuh khawh a si. (AFM) tahnak (Supplementary Fig. 2). Nanosheets pawl an i fonhnak zong an tlawm tuk caah hmuh khawh a si.
Ni(OH)2-NS le NiV-LDH-NS i X-ray thlennak sining hna. FE, throughput, le AA current density cu b Ni(OH)2-NS le c NiV-LDH-NS ah aa dangmi potential ah. Palhnak tlawmpal nih catalyst pakhat hmangin aa hngat lomi tahnak pathum i a tlarimi thleidannak kha a langhter. d NV-LDH-NS i HRTEM hmanthlak. Tahnak: 20 nm. HAADF-STEM hmanthlak NiV-LDH-NS le aa pehtlaimi elemental map nih Ni (a sen), V (a sen), le O (a sen) an i phawtzamhnak a langhter. Tahnak: 100 nm. f Ni 2p3/2, g O 1 s, le h V 2p3/2 XPS data Ni(OH)2-NS (cunglei) le NiV-LDH-NS (tanglei). i FE le j cu 7 cycle chung catalysts pahnih cung i AA riantuannak hna an si. Palhnak tlawmpal nih catalyst pakhat hmangin aa hngatmi tahnak pathum i a tlarimi thleidannak kha a langhter i 10% chung ah a um. a-c le f-j caah raw data cu raw data file ah pek a si.
Cu hnu ah Ni(OH)2-NS nih COR cung ah a chuahpimi thil kha kan zohfel. Constant potential electrolysis hmangin, OER tel loin AA 80% FE cu a tlawmmi potential (1.5 VRHE) ah kan hmuh (Figure 2b), cu nih cun COR cu anodic potential niam ah OER nakin thazaang lei in a ttha deuh ti a langhter. A chuakmi thil ttha bik cu glutaric acid (GA) a si i FE 3% a si. Succinic acid (SA), malonic acid (MA), le oxalic acid (OA) hna an um le um lo zong HPLC in tah a si (thilri phawtzamhnak caah Supplementary Figure 3 zoh). Thilchuak ah formic acid pakhat hmanh hmuh a si lo, cu nih cun carbonate cu C1 thilchuak pakhat in a chuak kho men tiah a langhter. Hi ruahnak cheuhnak hneksaknak caah, 0.4 M cyclohexanone tling tein electrolyse in a chuakmi electrolyte cu acid ah ser a si i, gas bantuk thilri pawl cu Ca(OH)2 cawhmi chungin an luhter hna. Cu ruangah, a cawhmi cu a thurhnawm, electrolysis hnu ah carbonate a chuah kha a fehter. Sihmanhsehlaw, electrolysis tuah lio ah a chuakmi electric thazaang dihlak a tlawm caah (Figure 2b, c), carbonate a tlawm i zat tuak a har. Cun, C2-C5 thilri dang zong an chuak kho, asinain an zat cu tuak khawh a si lo. Thilri dihlak zat tuak a har ko nain, electrochemical tlukruannak dihlak 90% nih electrochemical kalning tam deuh cu hngalh khawh a si cang ti a langhter, cucu kan mechanistic hngalhthiamnak caah hrampi a kan pek. A tlawmmi current density (20 mA cm−2) ruangah, AA chuahmi cu 97 μmol cm−2 h−1 (Figure 2b) a si, 19 mmol h−1 g−1 he aa tluk, cucu catalyst (5 mg cm−2) a ritmi cung ah hram bunh in a si, cucu thermal catalytic chuah khawhnak (~10 mm h−1 g−1) nakin a niam deuh. A hmanmi thilti khawhnak cu 1.5 in 1.9 VRHE tiang a karh tikah, a dihlak in a tthawnnak a karh ko nain (20 in 114 mA cm−2 tiang), AA FE ah 80% in 42% tiang a zor ngaingai. A ttha deuhmi thil ti khawhnak ah FE a zornak cu OER caah zuamnak ruangah a si bik. A hlei in 1.7 VRHE ah, OER zuamnak nih AA FE ah tlawmternak nganpi a chuahter, cucaah AA riantuan ning tlawmpal a zorter i a dihlak in a tu lio a karh. Cucaah, AA i a cheuchum current density cu 16 in 48 mA cm−2 tiang a karh i AA chuah khawhnak a karh (97 in 298 μmol cm−2 h−1) ko nain, thazaang tampi chap a si (1.5 in 1.9 VRHE tiang 2.5 W h gAA−1 tam deuh), cu nih cun carbon chuahnak a karhter. gAA−1 (tuaktannak konglam cu Supplementary Note 1 ah pek a si). A hlan ah langhtermi OER cu anodic thazaang sang ah COR lehrulhnak he aa zuammi a si i a hlan i reports he aa tlak i AA chuah khawhnak tthanchoternak caah a tlangpi in zuamcawhnak a aiawh14,17.
A ttha deuhmi Ni(OH)2-NS-based COR catalyst ser khawhnak dingah, a hmasa bik ah a cawlcangmi tthen kha kan hlathlai. Kan in situ Raman spectroscopy hmuhmi (Supplementary Fig. 4) ah 473 cm-1 le 553 cm-1 ah a sangbik kan hmuh, NiOOH chung i Ni3+-O pehtlaihnak hna i an i mernak le an i hlernak he aa tlak. NiOOH cu Ni(OH)2 zorternak le Ni(OH)O khonnak anodic potentials ah a chuakmi a si ti kha cazin ah khumh a si cang, cun a hrampi in electrocatalytic oxidation ah a cawlcangmi dirhmun a si20,21. Cucaah, Ni(OH)2 in NiOOH ah thlennak riantuannak kha rang deuh in tuahnak nih COR i catalytic cawlcanghnak kha a ṭhanchoter khawh lai tiah kan ruah.
Ni(OH)2 cu thir phunphun in remh kan i zuam, zeicahtiah heteroatom remhnak nih thlennak thir oxides/hydroxides ah a tthencheunak a thanchoter ti hmuh a si22,23,24. Sample pawl cu Ni le a pahnihnak thir precursor fonh in an ser hna. Thir-thlenmi sample phunphun lakah, V-thlenmi sample (V:Ni atomic ratio 1:8) (NiV-LDH-NS tiah auhmi) nih COR (Supplementary Fig. 5) ah a sang deuhmi current density a langhter i a biapi deuhmi cu, a kau ngaimi potential window cung ah AA FE a sang deuhmi a langhter. A bik in, a tlawmmi thilti khawhnak (1.5 VRHE) ah, NiV-LDH-NS i a tu lio a ritmi cu Ni(OH)2-NS nakin a let 1.9 in a sang deuh (39 vs. 20 mA cm−2), cun AA FE cu catalysts pahnih ah aa tluk (83% vs. 80%). Current density a sang deuhmi le aa lo ngaimi FE AA ruangah, NiV-LDH-NS chuah khawhnak cu Ni(OH)2-NS (204 vs. 97 μmol cm−2 h−1) nakin a let 2.1 in a sang deuh, cu nih cun V remhnak nih a niam deuhmi potentials ah current density a thanchotermi a langhter (Figure 2c).
A hmanmi thilti khawhnak (tahchunhnak ah, 1.9 VRHE) a karh tikah, NiV-LDH-NS cung i a tu lio a ritmi cu Ni(OH)2-NS (170 vs. 114 mA cm−2) nakin a let 1.5 in a sang deuh, cun a karhmi cu a niam deuhmi thilti khawhnak (a let 1.9 a sang deuh) he aa lo. A hlei in, NiV-LDH-NS nih a sangmi AA FE (83%) kha a tlaih peng i OER cu a tlawm ngaingai (O2 FE 4%; Figure 2c), Ni(OH)2-NS le a hlan ah report tuahmi catalysts pawl kha a niam deuhmi AA FE he a sangmi anodic potentials (Supplementary Table 1) nakin a ttha deuh. AA FE a sang tuk caah a kau ngaimi thil ti khawhnak window (1.5–1.9 VRHE) ah, AA chuahternak rate 867 μmol cm−2 h−1 (174.3 mmol g−1 h−1 he aa tluk) cu 1.9 VRHE ah hmuh khawh a si, cu nih cun electrocatalytic le thethercatatic hmanh ah a ttha mi riantuan ning a langhter tikah a dihlak in a ttha mi riantuannak nih a ttha mi riantuannak a langhter NiV-LDH-NS sample pawl phorh (Supplementary Fig. 6).
Ni(OH)2 kha V in remh hnu ah a kau ngaimi thil ti khawhnak hmun cung ah a sangmi current density le a sangmi FE hngalhthiam awkah, NiV-LDH-NS dirhmun kha kan langhter. XRD hmuhmi nih a langhter mi cu V he remhnak nih β-Ni(OH)2 in α-Ni(OH)2 ah thlennak a chuahter, cun V he aa pehtlaimi crystalline phun pakhat hmanh an hmu lo (Fig. 2a). HRTEM hmuhmi nih a langhter mi cu NiV-LDH-NS nih a tlawm tukmi Ni(OH)2-NS nanosheets hna i an muisam kha a co i a kam lei ah aa khatmi a si (Fig. 2d). AFM tahnak nih nanosheets pawl i an i fonhnak a fekmi a langhter, cu nih cun tah khawhmi 7 nm hrawng a thuhnak a chuahter (Supplementary Fig. 7), cucu Ni(OH)2-NS (a thuhnak: 2–3 nm) nakin a ngan deuh. Energy-dispersive X-ray spectroscopy (EDS) mapping hlathlainak (Figure 2e) nih V le Ni elements cu nanosheets ah ttha tein an i tthen ti a langhter. V i electronic sining le Ni cung i a thlennak fianternak caah, X-ray photoelectron spectroscopy (XPS) (Figure 2f–h) kan hman. Ni(OH)2-NS nih Ni2+ (855.6 eV ah nu sangbik, 861.1 eV ah satellite sangbik, Figure 2f)25 i a sining a langhter. Ni(OH)2-NS i O 1 s XPS spectrum cu a sangbik pathum ah ṭhen khawh a si, cu hna lakah 529.9, 530.9 le 532.8 eV ah a sangbik pawl cu lattice oxygen (OL), hydroxyl phu (Ni-OH) le a cunglei tlamtlinlonak (OA) ah aa hngatmi oxygen (OA) hna he aa pehtlaimi an si, (Figures 2g)26,27,28,29. V he remh hnu ah, V 2p3/2 peak a hung chuak, cucu 517.1 eV (V5+), 516.6 eV (V4+) le 515.8 eV (V3+) ah a ummi peak pathum ah aa ṭhen khawh, cu nih cun a sining chung i V phun cu a bik in oxidation sang dirhmun ah an um ti a langhter (Figure 2035, 2035). Cun, NiV-LDH-NS ah 855.4 eV ah Ni 2p sangbik cu Ni(OH)2-NS he tahchunh tikah a ttha lo lei in aa thlen (0.2 eV hrawng), cucu electron pawl cu V in Ni ah an i thlen ti a langhter. V remhnak hnu ah hmuhmi Ni a tlawm deuhmi valence dirhmun cu Ni K-edge X-ray absorption near-edge spectroscopy (XANES) hmuhmi he aa tlak (a tanglei “V Remhnak nih Catalyst Tlawmternak A Thawnter” timi ṭhen kha a tawinak in theih na duh ahcun zoh). Suimilam 1 chung COR thlopnak hnu ah NiV-LDH-NS cu NiV-LDH-POST tiah min an pek i transmission electron microscopy, EDS mapping, X-ray diffraction, Raman spectroscopy, le XPS tahnak hna hmangin tling tein sining an langhter (Supplementary Figs. 8 le 9). Catalysts cu ultrathin nanosheet morphology (Supplementary Fig. 8a–c) he aa fonhmi bantuk in an um. V thletnak le catalyst remhthannak ruangah sample pawl i an crystallinity a zor i V dat cu a zor (Supplementary Fig. 8d–f). XPS spectra nih V peak intensity a zorter (Supplementary Fig. 9), cucu V leaching ruangah a si. Cun, O 1s spectrum hlathlainak (Supplementary Fig. 9d) le electron paramagnetic resonance (EPR) tahnak (Supplementary Fig. 10) nih NiV-LDH-NS cung i oxygen a lawngmi zat cu electrolysis 1 h hnu ah a karh ti a langhter, cu nih cun NiV-LDH-NS cung i oxygen a lawngmi zat cu electrolysis 1 h hnu ah a karh, cu nih cun NiV-LDH-NS binding energy ah a ttha lomi thlennak a chuahter khawh ( Supplementary Fig. 9d le Supplementary Fig. 9 10 ah fiang deuh in theih na duh ahcun)26,27,32,33. Cucaah, NiV-LDH-NS nih COR 1 h hnu ah a sining thlennak tlawmte lawng a langhter.
COR thanchoternak ah V nih a biapi tukmi rian a ttuanmi fehternak caah, 1:8 dah ti lo cu coprecipitation phunglam ning tein aa dangmi V:Ni atomic ratio (1:32, 1:16, le 1:4, NiV-32, NiV-16, le NiV-4 tiah min an pekmi) he NiV-LDH catalysts kan ser. EDS mapping hmuhmi nih a langhter mi cu catalyst chung i V:Ni atomic ratio cu a hlan i a ummi he aa naih (Supplementary Fig. 11a–e). V remhnak a karh tikah, V 2p spectrum a tthawnnak a karh, cun Ni 2p pengtlang i pehtlaihnak thazaang cu a ttha lomi lei ah aa thlen peng (Supplementary Fig. 12). Cu lio caan te ah cun, OL zat cu zaangfah tein a karh. Catalytic hneksaknak a phichuak nih a langhter mi cu OER cu a tlawm bik V remhnak (V:Ni atomic ratio 1:32) hnu zongah ttha tein kham khawh a si, V remhnak hnu ah 1.8 VRHE ah O2 FE cu 27% in 11% tiang a zor (Supplementary Fig. 11f). V:Ni ratio 1:32 in 1:8 tiang a karh tikah, catalytic cawlcanghnak a karh. Sihmanhsehlaw, V remhnak a karh chin lengmang tikah (V:Ni ratio 1:4), a tu lio a ritmi a zor, cucu Ni active sites (a bik in NiOOH active phase; Supplementary Fig. 11f) a zor caah a si tiah kan ruah. V remhnak le Ni a cawlcangmi hmun pawl kilvennak nih a chuahpimi thil ruangah, V:Ni ratio 1:8 a ngeimi catalyst nih V:Ni ratio thleidannak hneksaknak ah FE le AA riantuannak a sang bik a langhter. Electrolysis hnu ah V:Ni ratio cu aa thleng lo maw ti fianternak caah, hmanmi catalysts pawl an i fonh ning kha an langhter. A phichuak nih a langhter mi cu a hramthawk V:Ni ratio 1:16 in 1:4 tiang a ngeimi catalysts caah, V:Ni ratio cu 1:22 hrawng ah a zor, cucu catalyst remhthannak ruangah V a chuah ruangah a si kho men (Supplementary Fig. 13). A hramthawk V:Ni ratio cu 1:16 (Supplementary Fig. 11f) he aa tluk asiloah a sang deuh tikah aa tlukmi AA FEs hmuh a si ti kha philh hlah, cucu catalyst remhnak nih aa khatmi catalytic riantuan ning a langhtermi catalyst ah aa lo ngaimi V:Ni ratio a chuahtermi nih a fianter khawh.
COR riantuan ning tthanchoternak ah V-modified Ni(OH)2 a biapitnak fehternak caah, Ni(OH)2-NS thilri chungah V luhternak caah a dang sernak lam pahnih kan ser. Pakhat cu cawhnak lam a si, cun zohchunhmi cu NiV-MIX tiah auhmi a si; a dang pakhat cu a zulmi thletnak lam a si, cun zohchunhmi cu NiV-SP tiah auhmi a si. A fonhmi konglam cu Lamthluan timi ṭhen ah pek a si. SEM-EDS mapping nih V cu sample pahnih Ni(OH)2-NS cunglei ah hlawhtling tein remh a si ti a langhter (Supplementary Fig. 14). Electrolysis hmuhmi nih a langhter mi cu 1.8 VRHE ah, NiV-MIX le NiV-SP electrode cung i AA tthatnak cu 78% le 79% a si, an pahnih in Ni(OH)2-NS (51%) nakin tthatnak sang deuh an langhter. Cun, NiV-MIX le NiV-SP electrode cung i OER cu Ni(OH)2-NS (FE O2: 27%) he tahchunh tikah a zor (FE O2: 7% le 2%, ciocio). Hi hmuhmi nih hin Ni(OH)2 chung i V remhnak nih OER khamnak ah a tthatnak a chuahpi ti kha a fehter (Supplementary Fig. 14). Sihmanhsehlaw, catalysts hna i an fekmi cu a rawk, cucu COR cycle pasarih hnu ah NiV-MIX cung i FE AA 45% le NiV-SP cung i 35% tiang a zornak nih a langhter, cucu V phun pawl fek tein chiah khawhnak ding caah aa tlakmi lam hman a herhnak a langhter, cu bantuk cu Ni(OH)2 latti ah V remhnak Nice-HLD-HLD ah a si, cucu a biapi bikmi a si hi rian ah hin.
Ni(OH)2-NS le NiV-LDH-NS hna i an fekmi zong kha COR kha voi tampi thlennak in kan tuaktan. Cu thlennak cu cycle pakhat ah 1 h chung tuah a si i cycle pakhat hnu pakhat ah electrolyte cu thlen a si. A voi 7nak hnu ah, Ni(OH)2-NS cung i FE le AA riantuannak cu 50% le 60% in a zor, cu lio ah OER a karhmi hmuh a si (Fig. 2i, j). Cycle pakhat cio hnu ah, catalysts hna i cyclic voltammetry (CV) curves kha kan hlathlai i Ni2+ oxidation peak cu a zor thluahmah ti kha kan hmuh, cucu Ni redox thilti khawhnak a zor ti a langhter (Supplementary Fig. 15a–c). Electrolysis tuah lio ah electrolyte chung i Ni cation a karh he (Supplementary Fig. 15d), riantuan ning a rawhnak (FE le AA chuah khawhnak a zor) cu catalyst chungin Ni a chuah ruangah a si tiah kan ruah, cu nih cun OER cawlcanghnak a langhtermi Ni foamed substrate a langhter deuh. Cu he aa dang in, NiV-LDH-NS nih FE le AA chuah khawhnak a zornak kha 10% tiang a zorter (Fig. 2i, j), cucu V remhnak nih Ni chuahnak kha ttha tein a kham ti a langhter (Supplementary Fig. 15d). V remhnak a tthanchomi fekmi hngalhthiam awkah, ruahnak tuaktannak kan tuah. Hlanlio cauk34,35 ning in, catalyst a cawlcangmi cunglei ah thir atom hna i thir tlawmternak kalning i enthalpy thlennak cu catalyst fekmi tuaktannak caah aa tlakmi fianternak ah hman khawh a si. Cucaah, remh ṭhanmi Ni(OH)2-NS le NiV-LDH-NS (NiOOH le NiVOOH, ciocio) cunglei (100) cung i Ni atom hna i thir thlennak kalning i enthalpy thlennak kha tuaktan a si (model sernak konglam cu Supplementary Note 2 le Supplementary Fig. 16 ah langhter a si). NiOOH le NiVOOH chungin Ni thir thlennak kalning cu langhter a si (Supplementary Fig. 17). NiVOOH (0.0325 eV) cung i Ni demetallization thazaang man cu NiOOH (0.0005 eV) cung nakin a sang deuh, cu nih cun V remhnak nih NiOOH a fekmi a ṭhanchoter ti a langhter.
NiV-LDH-NS cung i OER khamnak riantuannak fehternak caah, a hlei in anodic thazaang sang ah, aa dangmi electrochemical mass spectrometry (DEMS) cu sample dangdang cung ah thazaang-a hngatmi O2 sernak hlathlainak tuah a si. A phichuak nih a langhter mi cu cyclohexanone a um lo ahcun, NiV-LDH-NS cung i O2 cu a hramthawk ah 1.53 VRHE a si, cucu Ni(OH)2-NS (1.62 VRHE) cung i O2 nakin tlawmpal a niam deuh (Supplementary Fig. 18). Hi hmuhmi nih hin COR chung ah NiV-LDH-NS OER khamnak cu a chunglei OER cawlcanghnak a niam ruangah a si kho men lo ti a langhter, cucu NiV-LDH-NS cung i linear sweep voltammetry (LSV) curves ah cyclohan tel loin Ni(OH)2-NS cung nakin tlawmpal a sang deuhmi current density he aa tlak (Figu. 19). Cyclohexanone an luhpi hnu ah, O2 thlennak a tlai (COR thermodynamic ṭhatnak ruangah a si kho men) nih a niam deuhmi hmun ah AA FE a sangmi kha a fianter. A biapi deuhmi cu, NiV-LDH-NS (1.73 VRHE) cung i OER thawk khawhnak cu Ni(OH)2-NS (1.65 VRHE) nakin a tlai deuh, cucu AA FE sang le NiV-LDH-NS cung i O2 FE niam he aa tlak (Figure 2c).
V remhnak nih a chuahpimi thil sining hngalhthiam deuh awkah, Ni(OH)2-NS le NiV-LDH-NS cung i OER le COR lehrulhnak kinetics kha an Tafel slopes tahnak in kan hlathlai. Tafel pengkulh chung i a tu lio a ritmi cu LSV hneksaknak tuah lio ah Ni2+ in Ni3+ ah a thlennak ruangah a si ti kha hngalh awk tlak a si. COR Tafel slope tahnak ah Ni2+ oxidation nih a chuahpimi thil kha zorter awkah, 1.8 VRHE ah 10 min chung catalyst kha oxidize kan tuah hmasa i cu hnuah LSV hneksaknak kha reverse scan mode in kan tuah, cucu, a sangmi in a niammi tiang (Supplementary Fig. 20). Tafel slope hmuh khawhnak dingah a hramthawk LSV curve cu 100% iR tlukruannak in remh a si. Cyclohexanone a um lo ahcun, NiV-LDH-NS (41.6 mV dec−1) Tafel slope cu Ni(OH)2-NS (65.5 mV dec−1) nakin a niam deuh, cu nih cun OER kinetics cu V remhnak in a ṭhanchoter khawh ti a langhter (Supplementary Fig. 20c). Cyclohexanone an luhpi hnu ah, NiV-LDH-NS (37.3 mV dec−1) Tafel slope cu Ni(OH)2-NS (127.4 mV dec−1) nakin a niam deuh, cu nih cun V remhnak nih OER he tahchunh tikah COR cungah a fiang deuhmi kinetic effect a ngei ti a langhter (Supplementary Fig. 20). Hi hmuhmi nih hin V remhnak nih OER kha tlawmpal a thanchoter ko nain, COR kinetics kha a rangter ngaingai, cu nih cun AA FE a karhter ti kha a langhter.
A cunglei V remhnak nih FE le AA riantuan ning a tthanchoter ning hngalhthiam khawhnak dingah, mechanism hlathlainak ah kan i hngat. A hlan i report cheukhat nih heteroatom remhnak nih catalysts hna i an crystallinity kha a zorter khawh i electrochemically active surface area (EAS) a karhter khawh, cucaah a cawlcangmi hmun hna kha a karhter khawh i cucaah catalytic cawlcanghnak kha a tthanter khawh36,37. Hi thil cang khomi hlathlainak tuah awkah, electrochemical riantuannak hlan le hnu ah ECSA tahnak kan tuah, cun a phichuak nih Ni(OH)2-NS le NiV-LDH-NS ECSA cu aa tluk (Supplementary Fig. 21) a langhter, V remhnak hnu ah a cawlcangmi hmun tlawmtam nih catalytic tthanchonak cung ah a chuahpimi huham kha telh loin.
A tlangpi in cohlanmi hngalhnak ningin, Ni(OH)2-catalyzed electrooxidation of alcohols asiloah a dang nucleophilic substrates ah, Ni(OH)2 nih a hmasa bik ah electrons le protons a sungh hna i cu hnu ah anodic potential pakhatkhat ah electrochemical steps hmangin NiOOH ah a zorter38,39,40,41. A chuakmi NiOOH nih cun a taktak in a cawlcangmi COR phun bantukin rian a ttuan i nucleophilic substrate chungin hydrogen le electron pawl kha chemical step hmangin a chuah hna i oxidized thilri a ser20,41. Sihmanhsehlaw, naite ah NiOOH ah tlawmternak cu Ni(OH)2 cung i zu electrooxidation caah rate-determining step (RDS) ah a hman ko nain, naite cauk ah ruahnak cheuh a si bantukin, Ni3+ zu pawl oxidation cu Ni3+14,142 i a um lomi orbitals chungin non-redox electron thlennak in a chuakmi thil a si kho tiah report an tuah. Cauk pakhat ah langhtermi mechanistic hlathlainak in thazaang kan lak i, COR chung Ni3+ zornak in a chuakmi Ni2+ sernak paohpaoh kha in situ ah tlaih khawhnak ding caah dimethylglyoxime disodium salt octahydrate (C4H6N2Na2O2 8H2O) kha probe molecule ah kan hman (Supplementary Fig. 22 le Supplementary Note 3). A phichuak nih Ni2+ sernak a langhter, NiOOH chemical tlawmternak le Ni(OH)2 electrooxidation cu COR tuahsernak chungah hmunkhat te ah a cang ti kha a fehter. Cucaah, catalytic cawlcanghnak cu Ni(OH)2 in NiOOH ah a zorternak kinetics cungah tampi aa hngat kho. Hi phunglam cungah hram bunh in, V remhnak nih Ni(OH)2 zorternak a rangter lai i cucaah COR a tthanchoter lai maw ti kha kan hlathlai tthan.
NiOOH cu Ni(OH)2-NS le NiV-LDH-NS cung i COR caah a cawlcangmi dirhmun a si ti langhternak caah in situ Raman thiamnak kha kan hman hmasa i, a cunglei “electrochemical process” (Figure 3) zulh in, a ṭhami thilti khawhnak ah NiOOH a chuahkehnak le cyclohexanone luhternak hnu ah a hmannak kha zoh in kan hman. Cun, remh ṭhanmi NiV-LDH-NS i a lehrulhnak nih Ni(OH)2-NS nakin a lonh, Ni3+–O Raman signal a rang tukmi a tlaunak nih a langhter. Cu hnu ah NiV-LDH-NS nih Ni(OH)2-NS he tahchunh tikah cyclohexanone a um le um lo ah NiOOH sernak caah a tlawm deuhmi a tthatnak a langhter ti kha kan langhter (Figure 3b, c le Supplementary Fig. 4c, d). A hlei in, NiV-LDH-NS i a ttha deuhmi OER riantuannak nih Raman tahnak thilri hmailei lens ah bubble tam deuh a hren, cu nih cun 1.55 VRHE ah Raman peak a tlauter (Supplementary Fig. 4d). DEMS hmuhmi (Supplementary Fig. 18) ning in, a niam mi tthawnnak (VRHE < 1.58 for Ni(OH)2-NS le VRHE < 1.53 for NiV-LDH-NS) ah a tu lio tthawnnak cu cyclohexone um lonak ah OER nakin Ni2+ ions sersiam tthannak ruangah a si bik. Cucaah, LSV curve chung i Ni2+ oxidation peak cu NiV-LDH-NS nakin a tthawng deuh, cu nih cun V remhnak nih NiV-LDH-NS kha a tthanchomi remh khawhnak a pek ti a langhter (a tlingmi hlathlainak caah Supplementary Fig. 19 zoh).
a Ni(OH)2-NS (kehlei) le NiV-LDH-NS (orhlei) hna i OCP dirhmun tangah 1.5 VRHE ah 0.5 M KOH le 0.4 M cyclohexanone ah 60 s chung preoxidation tuah hnu ah an umnak hmun Raman spectra. b 0.5 M KOH + 0.4 M cyclohexanone ah Ni(OH)2-NS le c NiV-LDH-NS hna i an hmunhma ah Raman spectra. d Ni(OH)2-NS le NiV-LDH-NS i Ni K-edge ah 0.5 M KOH le e 0.5 M KOH le 0.4 M cyclohexanone ah a ummi XANES spectra. A chunglei nih 8342 le 8446 eV karlak ah a ngan deuhmi spectral region a langhter. f Ni(OH)2-NS le NiV-LDH-NS ah Ni i a tthawnnak aa dangmi dirhmun. g Cyclohexanone luhternak hlan le hnu ah NiV-LDH-NS i a hmunmi Ni EXAFS spectra cu a dangdang potentials ah. h Ni(OH)2-NS le NiV-LDH-NS i an ruahnak model hna. A cunglei: Ni(OH)2-NS ah, Ni(OH)2-NS in NiOOH ah tlawmpal in remh ṭhannak nih RDS bantukin rian a ṭuan, cu lioah cyclohexanone nih AA chuahter awkah a niammi Ni dirhmun kilven awkah chemical step hmangin a sangmi Ni phun kha a zorter. A tanglei: NiV-LDH-NS ah, remhthannak step cu V remhnak nih a bawmh, cu nih cun remhthannak step in chemical step ah RDS thlennak a chuahter. i Ni(OH)2-NS le NiV-LDH-NS ser ṭhan tikah Gibbs zalongmi thazaang aa thleng. aj le i caah raw data cu raw data file ah pek a si.
Catalyst tlawmternak lio ah atomic le electronic sining hna i an i thlennak kong hlathlainak tuah awkah, in situ X-ray absorption spectroscopy (XAS) hneksaknak kan tuah, cu nih cun Ni phun hna i an thlennak kha a hnu hnu in step pathum in hlathlainak tuahnak caah thilri ṭha a kan pek: OER, cyclohexanone injection, le COR at potential circuit (OCP). Hmanthlak nih hin Ni i K-edge XANES spectra cu cyclohexanone thun hlan le hnu ah a karh chin lengmangmi a langhter (Hmanthlak 3d, e). Cu tluk cun, NiV-LDH-NS i a laknak tthen thazaang cu Ni(OH)2-NS nakin a ttha deuh ngaingai (Figure 3d, e, inset). Thil sining pakhat cio tangah Ni a tlangpi tlukruannak cu XANES spectra le Ni K-edge laknak thazaang thlennak (Figure 3f) i a tlarimi fonhmi tlukruannak in tuak a si, chuahmi cauk chungin lakmi zohchunhnak spectrum he (Supplementary Fig. 23)43.
A hmasa bik ah (cyclohexanone luhternak hlan ah, OER kalning he aa tlakmi; Figure 3f, kehlei), remh ṭhan lomi catalyst (<1.3 VRHE) a ṭhawnnak ah, NiV-LDH-NS (+1.83) chung i Ni valence dirhmun cu Ni(OH)2-NS (+1.83) nakin tlawmpal a niam deuh, cucu V in electron ah thlen khawh a si (+1.97). Ni, a cunglei langhtermi XPS hmuhmi he aa tlak (Figure 2f). A tthawnnak nih tlawmternak hmun (1.5 VRHE) a lonh tikah, NiV-LDH-NS (+3.28) chung i Ni valence dirhmun nih Ni(OH)2-NS (+2.49) he tahchunh tikah a fiang deuhmi karhternak a langhter. A sang deuhmi thilti khawhnak (1.8 VRHE) ah, NiV-LDH-NS (+3.64) ah hmuhmi Ni particles hna i an valence dirhmun cu Ni(OH)2-NS (+3.47) nakin a sang deuh. Nai thawngpang ning in, hi thil kalning hi Ni3+xOOH1-x (Ni3+x cu Ni3+ le Ni4+ cawhmi phun a si) dirhmun ah a sangmi Ni4+ phun sernak he aa tlak, mah nih hin a hlan ah zu ti tlawmternak ah a tthanchomi catalytic cawlcanghnak a rak langhter cang38,39,44. Cucaah, COR ah NiV-LDH-NS riantuannak a ttha deuhmi cu catalytically active high-valent Ni phun sernak caah a tthanchomi tlawmternak ruangah a si kho men.
A pahnihnak ah (ring on hnu ah cyclohexanone luhternak, Figure 3f), catalysts pahnih cung i Ni valence dirhmun cu a zor ngaingai, cucu cyclohexanone nih Ni3+xOOH1-x a zorternak kalning he aa tlak, cucu in situ Raman spectroscopy (Figure 3f) hmuhmi he aa tlak, cun Ni valence dirhmun cu a hramthawk dirhmun ah a kir tthan deng cang (a tlawmmi tthawnnak ah a hmasa bik kehlan), Ni in Ni3+xOOH1-x ah redox kalning a kir khawhnak a langhter.
COR tthawnnak (1.5 le 1.8 VRHE; Figure 3f, orhlei) ah a pathumnak step (COR process) ah, Ni(OH)2-NS chung i Ni valence dirhmun cu tlawmpal lawng a karh (+2.16 le +2.40), cucu a hmasa bik step (+2.49 le +3.47) ah a tthawnnak aa khatmi nakin a niam deuh ngaingai. Hi hmuhmi nih hin cyclohexanone thun hnu ah, COR cu NiOOH le cyclohexanone karlak Ni(OH)2-NS cung i chemical step nih si loin Ni2+ in Ni3+x (cucu, Ni sersiam ṭhannak) a tlawmmi oxidation nih a tthawnnak in a kham ti a langhter, cu nih cun Ni kha a niam deuhmi dirhmun ah a chiah. Cucaah, Ni sersiam ṭhannak nih Ni(OH)2-NS cung i COR kalning ah RDS rian a ṭuan khawh tiah kan donghter. Cu he aa dang in, NiV-LDH-NS nih COR tuah lio ah Ni phun (>3) a sangmi a ngeih peng, cun a tlawm deuh ngai (0.2 nak tlawm deuh) a tlawm deuh (0.2 nak tlawm deuh) ah a hmasa bik kehlan he tahchunh tikah aa khatmi thilti khawhnak (1.65 le 1.8 VRHE), cucu V remhnak nih Ni2+ oxidation kha Ni2+ ah a tthawnter deuh ti a langhter, cu nih cun Ni3+ riantuannak kha a rangter deuh cyclohexanone zorternak chemical step. Extended X-ray absorption fine structure (EXAFS) results zong nih cyclohexanone a um lio ah Ni–O (1.6 in 1.4 Å tiang) le Ni–Ni(V) (2.8 in 2.4 Å tiang) pehtlaihnak tling tein thlennak a langhter. Mah cu Ni(OH)2 tthennak kha NiOOH tthennak ah ser ṭhannak le cyclohexanone nih NiOOH tthennak chemical in a zorternak he aa tlak (Fig. 3g). Sihmanhsehlaw, cyclohexanone nih Ni(OH)2-NS tlawmternak kinetics kha a kham ngaingai (a konglam tam deuh theih na duh ahcun Supplementary Note 4 le Supplementary Fig. 24 zoh).
A dihlak in, Ni(OH)2-NS (Fig. 3h, cunglei) ah, Ni(OH)2 tthen in NiOOH tthen tiang tlawmpal in zorternak step nih NiOOH chemical tlawmternak lio ah cyclohexanone in AA sernak chemical step si loin a dihlak in COR process RDS ah rian a ttuan kho. NiV-LDH-NS ah (Fig. 3h, tanglei), V remhnak nih Ni2+ in Ni3+x ah oxidation kinetics a ṭhanchoter, cucaah NiVOOH sernak kha a rangter (chemical tlawmternak in hmannak nakin), cu nih cun RDS kha chemical step lei ah a thlen. V remhnak nih a chuahtermi Ni sersiam ṭhannak hngalhthiam awkah, ruahnak lei tuaktannak dang kan tuah. Fig. 3h ah langhter bantuk in, Ni(OH)2-NS le NiV-LDH-NS remhthannak kalning kha kan i zohchunh. Ni(OH)2-NS le NiV-LDH-NS cung i lattice hydroxyl phu pawl cu electrolyte chungin OH- chuah in deprotonate an si i electron-deficient lattice oxygen an ser. Aa pehtlaimi chemical thlennak hna cu a tanglei bantuk in an si:
Remhthannak i Gibbs zalongmi thazaang thlennak cu tuak a si (Figure 3i), cun NiV-LDH-NS (0.81 eV) nih Ni(OH)2-NS (1.66 eV) nakin Gibbs zalongmi thazaang thlennak a hme deuhmi a langhter, cu nih cun V remhnak nih Ni remhthannak caah a herhmi voltage a zorter ti a langhter. Remhthannak thanchoternak nih COR dihlak thazaang khamnak kha a zorter khawh tiah kan zumh (a tanglei ah a ummi lehrulhnak mechanism hlathlainak kha zoh), cucaah a sang deuhmi current density ah lehrulhnak kha a rangter.
A cunglei hlathlainak nih a langhter mi cu V remhnak nih Ni(OH)2 a rangmi tthencheunak a chuahter, cu nih cun thlennak rate a karhter i, cu nih cun, COR current density a karhter. Sihmanhsehlaw, Ni3+x hmun hna nih OER cawlcanghnak zong a thanchoter khawh. Cyclohexanone tel loin LSV curve in, NiV-LDH-NS i a tu lio density cu Ni(OH)2-NS nakin a sang deuh ti a fiang (Supplementary Fig. 19), cu nih cun COR le OER i pehtlaihnak kha zuamnak i thlennak a chuahter. Cucaah, NiV-LDH-NS nakin AA FE a sang deuhmi cu V remhnak nih phase rearrangement a thanchotermi nih tling tein a fianter kho lo.
Alkaline media ah, nucleophilic substrates i electrooxidation lehrulhnak nih Langmuir-Hinshelwood (LH) model kha a zulh tawn ti cu a tlangpi in cohlan a si. A bik in, substrate le OH− anions cu catalyst cunglei ah zuamnak in coadsorb an si, cun adsorbed OH− cu active hydroxyl groups (OH*) ah oxidized a si, cu hna cu nucleophiles oxidation caah electrophiles rian an ttuan, mah cu a hlan ah hneksaknak data le/asiloah theoretical tuaktannak nih a langhter cangmi a si,44,46. Cucaah, reactants pawl an i fonhnak le an ratio (organic substrate le OH−) nih catalyst cunglei i reactant khuhnak kha a uk khawh, cucaah FE le target thilri chuahmi kha a hnorsuan14,48,49,50. Kan kong ahcun, NiV-LDH-NS ah cyclohexanone cunglei khuhnak sang nih COR kalning a bawmh tiah kan ruah, cun a dang tein, Ni(OH)2-NS ah cyclohexanone cunglei khuhnak tlawm nih OER kalning a bawmh tiah kan ruah.
A cunglei ruahnak hneksaknak caah, a hmasa bik ah a cawlcangmi thilri (C, cyclohexanone, le COH−) an i fonhnak he aa pehtlaimi hneksaknak phun hnih kan tuah. A hmasa bik hneksaknak cu Ni(OH)2-NS le NiV-LDH-NS catalysts cung ah aa dangmi cyclohexanone C aa telmi (0.05 ~ 0.45 M) le aa thleng lomi COH− aa telmi (0.5 M) he aa thleng lomi thilti khawhnak (1.8 VRHE) ah electrolysis in tuah a si. Cun, FE le AA chuah khawhnak kha an tuak. NiV-LDH-NS catalyst caah, AA chuahmi le cyclohexanone C karlak pehtlaihnak nih LH mode ah a tlangpi in “meitlang phun” a langhter (Fig. 4a), cu nih cun cyclohexanone khuhnak sang nih OH− laknak he aa zuam ti a langhter. Ni(OH)2-NS caah cun, AA chuahmi cu cyclohexanone C 0.05 in 0.45 M tiang a karh tikah aa khat tein a karh, cucu cyclohexanone a tam deuh (0.45 M) a si ko nain a cunglei khuhnak cu a niam deuh rih ti a langhter. Cun, COH− 1.5 M tiang a karh tikah, cyclohexanone C cung ah aa hngatmi Ni(OH)2-NS cung ah “meitlang phun” tlukruannak hmuh a si, cun NiV-LDH-NS he tahchunh tikah riantuannak i thlennak hmun cu a tlai deuh, NiV-LDH-NS he tahchunh tikah cyclohexanone nih a derthawmmi a laknak kha a langhter chin. le Note 5). Cun, NiV-LDH-NS cung i AA FE cu C-cyclohexanone cungah a ttha tuk i C-cyclohexanone cu 0.05 M in 0.3 M tiang an karhter tikah 80% nak tam tiang rang tukin a karh, cu nih cun cyclohexanone cu NiV-LDH-NS cung ah fawi tein a rumter ti a langhter (Figure 4b). Cu he aa dang in, C-cyclohexanone tlawmternak nih Ni(OH)2-NS cung i OER kha a kham lo, cucu cyclohexanone a tlawm tuk caah a si kho men. Cu he aa ralchanh in, COH− nih catalytic tthatnak cung ah aa hngatchannak kong hlathlainak tuah chapnak nih cyclohexanone nih a lakmi cu NiV-LDH-NS he tahchunh tikah a ttha deuh ti zong a fehter, cu nih cun AA FE a zorter loin COR tuahsernak chungah COH− sang deuh a tuar khawh (Supplementary Fig. 25b, c le Note 5).
0.5 M KOH ah C aa dangmi cyclohexanone cung i b Ni(OH)2-NS le NiV-LDH-NS i AA le EF chuah khawhnak. c NiOOH le NiVOOH cung i cyclohexanone nih a lakmi thazaang. d AA FE cu Ni(OH)2-NS le NiV-LDH-NS ah 0.5 M KOH le 0.4 M cyclohexanone ah 1.80 VRHE ah aa pehtlaimi le aa thleng lomi thil ti khawhnak strategy hmangin. Palhnak tlawmpal nih sample pakhat hmangin aa hngatmi tahnak pathum i a tlarimi thleidannak kha a langhter i 10% chung ah a um. e A cunglei: Ni(OH)2-NS cung ah, a tlawmmi a cunglei C a ngeimi cyclohexanone cu cyclohexanone nih a derthawmmi in a lak, cu nih cun OER caah zuamnak fakpi a chuahter. A tanglei: NiV-LDH-NS ah, cyclohexanone C a sangmi a cunglei hmun ah cyclohexanone a laknak a karhmi he hmuh a si, cu nih cun OER kha a kham. a-d caah a hramthawk data cu a hramthawk data file ah pek a si.
NiV-LDH-NS cung i cyclohexanone a tthanchomi laknak hneksaknak caah, a caan hmaan tein lakmi phun hna i an ritmi thlennak zohfel awkah electrochemical coupled quartz crystal microbalance (E-QCM) kan hman. A phichuak nih a langhter mi cu NiV-LDH-NS cung i cyclohexanone nih a hramthawk ah a lak khawhnak cu OCP dirhmun ah Ni(OH)2-NS nakin a let 1.6 in a ngan deuh, cun hi lak khawhnak aa dannak cu 1.5 VRHE tiang a karh tikah a karh chin lengmang (Supplementary Fig. 26). NiOOH le NiVOOH cung i cyclohexanone nih a lakmi ziaza hlathlainak caah spin-polarized DFT tuaktannak an tuah (Figure 4c). Cyclohexanone nih NiOOH cung i Ni-center ah -0.57 eV tlukruannak thazaang (Eads) he a luhhnawh, cu lio ah cyclohexanone nih Ni-center asiloah NiVOOH cung i V-center ah a luhhnawh khawh, cuka ahcun V-center nih Eads (-0.69 eV) a niam deuhmi a pek, hmuhmi a tthawngmi laknak he aa tlak NiVOOH cung i cyclohexanone.
Cyclohexanone a tthanchomi laknak nih AA sernak a thanchoter khawh i OER a kham khawh ti kha fehter chin awkah, a hlan report hna nih a forhmi a simi catalyst cunglei ah cyclohexanone (Ni(OH)2-NS le NiV-LDH-NS caah) ṭhanchoternak caah aa pehzulh lomi thil ti khawhnak strategy kha kan hman. 51, 52 A bik in, COR ah 1.8 VRHE a si khomi kan hman, cun OCP dirhmun ah kan thlen, cun 1.8 VRHE ah kan thlen tthan. Hi kongah, cyclohexanone cu electrolyses karlak ah OCP dirhmun ah catalyst cunglei ah aa pum kho (a tlingmi tuahsernak caah Methods timi ṭhen kha zoh). A phichuak nih a langhter mi cu Ni(OH)2-NS le NiV-LDH-NS caah, aa pehtlaimi thilti khawhnak electrolysis hmannak nih aa pehtlaimi thilti khawhnak electrolysis he tahchunh tikah catalytic riantuan ning a tthanchoter (Figure 4d). A hlei in, Ni(OH)2-NS nih NiV-LDH-NS nakin COR (AA FE: 51% in 82%) le OER (O2 FE: 27% in 4%) khamnak ah a lang deuhmi tthanchonak a langhter, cucu cyclohexanone khonnak cu cataker adsortion (a tthawnnak) he a tam deuh in a tthancho khawh caah a si tiah an ti. Ni(OH)2-NS) cu a caancaan ah a cang khomi electrolysis in.
A dihlak in, NiV-LDH-NS cung i OER khamnak cu cyclohexanone a tthanchomi laknak ruangah a si kho (Figure 4e). Ni(OH)2-NS (Figure 4e, cunglei) ah, cyclohexanone a derthawmmi nih a tlawm deuhmi cyclohexanone khuhnak le catalyst cunglei ah OH* khuhnak a sang deuhmi a chuahter. Cucaah, a tam tukmi OH* phun nih OER caah zuamnak fakpi a chuahter lai i AA FE a zorter lai. Cu he aa dang in, NiV-LDH-NS (Figure 4e, tanglei) ah, V remhnak nih cyclohexanone a lak khawhnak a karhter, cucaah cyclohexanone a cunglei C a karhter i COR caah a lakmi OH* phun kha ttha tein a hman, AA sernak a thanchoter i OER a kham.
Ni phun le cyclohexanone laknak ah V remhnak nih a chuahpimi thil sining hlathlainak lengah, V nih COR in AA sernak lam a thlen maw thlen lo ti zong kan hlathlai. Cauk chungah COR lam phunphun tampi an chuahpi cang, cun kan lehrulhnak system ah an si khawhnak kha kan hlathlai (a konglam tam deuh caah Supplementary Fig. 27 le Supplementary Note 6 zoh)13,14,26. Pakhatnak ah, COR lamthluan i a hmasa bik kehlan ah a biapi bikmi karlak 2-hydroxycyclohexanone (2)13,14 sernak caah cyclohexanone a hramthawk oxidation aa tel kho tiah report an tuah. A kalning fehternak caah, 5,5-dimethyl-1-pyrrolidine N-oxide (DMPO) hmangin catalyst cunglei ah aa hngatmi a cawlcangmi thilri pawl kha kan tlaih hna i EPR kha kan hlathlai. EPR hmuhmi nih COR tuah lio ah C-centered radicals (R ) le hydroxyl radicals (OH ) hna cu catalysts pahnih cungah an um ti a langhter, cu nih cun cyclohexanone i Cα − H dehydrogenation nih a karlak enolate radical (1) a ser ti a langhter, cu cu OH* nih a thlen i 2 a ser (Fig. 5 le Supplement 28). Catalysts pahnih ah aa khatmi karlak thilri pawl hmuh an si ko nain, NiV-LDH-NS cung i R signal area fraction cu Ni(OH)2-NS nakin a sang deuh, cucu cyclohexanone (Supplementary Table 3 le Note 7) i a tthanchomi adsorption ruangah a si kho men. Cun 2 le 1,2-cyclohexanedione (3) kha electrolysis caah a hramthawknak reactants ah kan hman i V nih a hnu oxidation step kha a remh lai maw ti hneksaknak caah kan hman. Ni(OH)2-NS le NiV-LDH-NS cung i a chuak khomi thilri (2 le 3) hna i electrolysis hmuhmi nih aa khatmi thilri thimnak a langhter, cu nih cun Ni(OH)2-NS asiloah NiV-LDH-NS cung i COR lehrulhnak cu aa lo ngaimi lam in a kal ti a langhter (Figure 5b). Cun, AA cu 2 kha reactant ah hman a si tik lawngah a biapi bikmi thilchuak a si, cu nih cun AA cu 2 i Cα − Cβ bond tthennak in direct oxidation process in hmuh a si ti kha a langhter, a hnu ah 3 ah oxidation tuah loin catalysts pahnih cung ah, zeicahtiah 3 kha a hramthawknak reactant ah hman a si tikah GA ah aa thleng bik (S, Figures 29 30).
0.5 M KOH + 0.4 M cyclohexanone ah NiV-LDH-NS EPR signal. b 2-hydroxycyclohexanone (2) le 1,2-cyclohexanedione (3) i electrocatalytic hlathlainak hmuhmi. Electrolysis cu 0.5 M KOH le 0.1 M 2 asiloah 3 ah 1.8 VRE ah suimilam pakhat chung tuah a si. Palhnak tlawmpal nih catalyst pakhat hmangin aa hngat lomi tahnak pahnih i a tlarimi thleidannak kha a langhter. c Catalyst pahnih cung i COR nih a chuahpimi lehrulhnak lam hna kha ruahnak cheuhnak. d Ni(OH)2-NS (orhlei) le d NiV-LDH-NS (orhlei) cung i COR lam a langhtermi hmanthlak. A senmi thal nih V remhnak nih COR kalning ah a thanchotermi kedan pawl kha a langhter. a le b caah raw data cu raw data file ah pek a si.
A dihlak in, Ni(OH)2-NS le NiV-LDH-NS nih COR kha aa khatmi lam in an thlen ti kha kan langhter: cyclohexanone cu catalyst cunglei ah aa hngat, ti a tlawmter i electron a sungh i 1 a ser, cu hnuah OH* nih 2 a ser, cu hnuah multistep thlennak nih a chuahter (Figure Ac). Sihmanhsehlaw, cyclohexanone cu reactant ah hman tikah, OER zuamnak cu Ni(OH)2-NS cung lawng ah hmuh a si, cu lio ah 2 le 3 kha reactant ah hman tikah oxygen tlawm bik an lak. Cucaah, catalytic riantuannak ah hmuhmi aa dannak hna cu RDS thazaang khamnak le V remhnak nih a chuahtermi cyclohexanone lak khawhnak thlennak ruangah a si kho men, thlennak lam thlennak ruangah a si kho lo. Cucaah catalysts pahnih cung i lehrulhnak lam hna i RDS kha kan hlathlai. A cunglei langhtermi in situ X-ray acoustic spectroscopy hmuhmi nih a langhter mi cu V remhnak nih COR reaction chung i RDS kha remhthannak dirhmun in chemical dirhmun ah a thlen, NiOOH tthen le high-valent Ni phun kha NiV-LDH-NS ah a rawk lo in a chiah (Fig. 3f, Supplementary Fig. 24 le No 44). CV tahnak chung ah a dangdang a si khomi hmun hna i a tu lio a ritmi nih a langhtermi lehrulhnak kalning hna kha kan hlathlai chin (a tawinak caah Supplementary Fig. 31 le Note 8 zoh) cun H/D kinetic isotope thlennak hneksaknak kan tuah, cu nih cun NiV-LDH-NS cung i COR RDS nih Cα − α pehtlaihnak ah aa tel ti kha a langhter tlawmternak dirhmun si loin chemical dirhmun (a konglam tam deuh theih na duh ahcun Supplementary Fig. 32 le Note 8 zoh).
A cunglei hlathlainak cungah hram bunh in, V remhnak nih a chuahpimi thil vialte cu Figure 5d ah hmuh khawh a si. Ni(OH)2-NS le NiV-LDH-NS catalysts nih hin anodic thazaang sang ah a cunglei remhthannak an tuah i aa lo ngaimi lam in COR kha an catalyze. Ni(OH)2-NS (Figure 5d, kehlei) ah, COR tuah lio ah remh ṭhannak step cu RDS a si; NiV-LDH-NS cung ah (Figure 5d, orhlei), V remhnak nih remhthannak kalning kha a rangter ngaingai i RDS cu cyclohexanone Cα−H dehydrogenation ah a thlen i 1 a ser. Cun, cyclohexanone laknak cu V hmun ah a cang i NiV-LDH-NS ah a karh, cucu OER khamnak ah a bawmh.
NiV-LDH-NS i a ttha tukmi electrocatalytic riantuannak kha a kau ngaimi thil ti khawhnak hmun ah FE sang he ruah in, AA pehzulh tein chuah khawhnak ding caah MEA pakhat kan suai. MEA cu NiV-LDH-NS kha anode ah, chawlehnak PtRu/C kha cathode53 ah le anion i thlennak membrane (phun: FAA-3-50) (Figure 6a le Supplementary Fig. 33)54 hmangin fonh a si. A cunglei hlathlainak ah cell voltage a zor i AA FE cu 0.5 M KOH he tahchunh khawh a si caah, anolyte tlawmtam cu 1 M KOH (Supplementary Fig. 25c) ah a ttha bik in remh a si. LSV tthencheunak hna cu Supplementary Fig. 34 ah langhter an si, cu nih cun NiV-LDH-NS i COR tthatnak cu Ni(OH)2-NS nakin a sang deuh ti a langhter. NiV-LDH-NS a tthatnak langhter awkah, aa thleng lomi current electrolysis cu 50 in 500 mA cm−2 karlak step current density he tuah a si i aa pehtlaimi cell voltage kha khumh a si. A phichuak nih a langhter mi cu NiV-LDH-NS nih 300 mA cm−2 current density ah 1.76 V cell voltage a langhter, cucu Ni(OH)2-NS (2.09 V) nakin 16% hrawng a niam deuh, AA chuahnak ah a thazaang tthatnak a sang deuh ti a langhter (Fig. 6b).
A luangmi battery hmanthlak. b 1 M KOH le 0.4 M cyclohexanone ah 1 M KOH le 0.4 M cyclohexanone ah iR tlukruannak um loin cell voltage. c AA le FE nih Ni(OH)2-NS le NiV-LDH-NS cu aa dangmi current density ah an chuahter. Palhnak hri nih catalyst pakhat hmangin aa hngat lomi tahnak pahnih i a tlarimi thleidannak kha a langhter. d Kan riantuannak i a dang report tuahmi a luangmi battery system hna he tahchunhnak14,17,19. Reaction parameters le reaction sining hna cu Supplementary Table 2 ah fiang tein an langhter. e Caan saupi hneksaknak ah 200 le 300 mA cm−2 ah NiV-LDH-NS cung i AA cell voltage le FE, ciocio. Be caah raw data cu raw data file bantuk in pek a si.
Cu lio ah, Fig. 6c ah langhter bantuk in, NiV-LDH-NS nih a ttha mi FE (83% in 61%) kha a sang deuhmi current density (200 in 500 mA cm-2) ah a kilven, cucaah AA chuah khawhnak (1031 in 1900 μmol cm-2 h-1) a tthanchoter. Cu lio ah, electrolysis hnu ah cathode compartment ah adipic acid anions 0.8% lawng hmuh an si, cu nih cun kan kong ah cyclohexanone thlennak cu a biapi lo ti a langhter (Supplementary Fig. 35). Cu he aa dang in, a tu lio tthawnnak a karh tluk tein, Ni(OH)2-NS cung i AA FE cu 61% in 34% tiang a zor, cu nih cun AA chuah khawhnak (762 in 1050 μmol cm-2 h-1) tthanchoter a harter. A bik in, OER in a tthawngmi zuamnak ruangah AA riantuan ning cu tlawmpal hmanh a zor, cucaah AA FE cu a tu lio a ritmi a karh tikah a zor ngaingai (200 in 250 mA cm−2 tiang, Supplementary Fig. 5). Kan theih khawh tawk ahcun, NiV-LDH-NS catalysts he MEA hmannak catalytic hmuhmi nih Ni-based catalysts he a hlan ah report tuahmi flow reactors hna riantuan ning kha a lonh ngaingai (Supplementary Table 2). Cun, Fig. 6d ah langhter bantuk in, NiV-LDH-NS nih a ttha bikmi Co-based catalyst, ie, graphene-supported Co3O4 (Co3O4/GDY)17 he tahchunh tikah AA i a tu lio a tlawmtam, cell voltage le FE lei ah tthatnak a langhter. Cun, AA chuahnak ah thazaang hmanmi kha kan zohfel i AA hmanmi cu a niam tuk ti kan hmuh, 2.4 W h gAA-1 lawng 300 mA cm-2 current density le 1.76 V cell voltage ah (a tlingmi tuaktannak cu Supplementary Note 1 ah pek a si). A hlan ah langhtermi Co3O4/GDY caah 4.1 W h gAA-1 a ttha bikmi he tahchunh tikah, kan riantuannak ah AA chuah khawhnak caah hmanmi thazaang cu 42% in a zor i chuah khawhnak cu a let 4 in a karh (1536 vs. 319 μmol cm-2 h-1)17.
MEA ah caan sau AA chuah khawhnak caah NiV-LDH-NS catalyst a fekmi cu 200 le 300 mA cm-2 tlukruannak ah an tuak (Figure 6e). OH− cu a sang deuhmi current density ah a rang deuh in a dih caah, 300 mA cm-2 ah electrolyte tharchuah rate cu 200 mA cm-2 nakin a sang deuh (a tawinak caah “Electrochemical tahnak” timi ṭhen hmete zoh). Atu lio 200 mA cm-2 a ritmi ah, a tlangpi in COR tthatnak cu a hmasa 6 h ah 93% a si, cun 60 h hnu ah 81% tiang tlawmpal a zor, cu lio ah cell voltage cu 7% in tlawmpal a karh (1.62 V in 1.73 V tiang), a fekmi dirhmun a langhter. Current density cu 300 mA cm−2 tiang a karh tikah, AA tthatnak cu aa thleng lo (85% in 72% tiang a zor), asinain 46-h hneksaknak chungah cell voltage cu a karh ngaingai (1.71 in 2.09 V tiang, 22% he aa tlak). Riantuannak a rawhnak a ruang bik cu cyclohexanone nih anion thlennak membrane (AEM) a hrawh caah a si lai tiah kan ruah, cu nih cun electrolyzer cell i cell ralchanhnak le voltage a karhter (Supplementary Fig. 36), cu he cun anode in cathode ah electrolyte tlawmpal a luang, cu nih cun anoly volume a zorter i a ngolter a herh electrolysis. Cun, AA FE a zornak cu OER caah Ni foam onnak a bawmtu catalysts a luannak ruangah a si kho. A rawkmi AEM nih 300 mA cm−2 ah fekmi rawhnak ah a chuahpimi thlennak langhter awkah, 46 h electrolysis hnu ah AEM thar in kan thlen. Ruahning bantuk in, catalytic tthatnak cu fiang tein a hung kir tthan, cell voltage cu a hramthawk man (2.09 in 1.71 V tiang) tiang a zor ngaingai i a hnu 12 h electrolysis chung ah tlawmpal a karh (1.71 in 1.79 V tiang, 5% karh; Figure 6e).
A dihlak in, 200 mA cm−2 current density ah 60 h chung pehzulh tein AA chuah khawhnak fek tein kan hmuh khawh, cucu AA FE le cell voltage cu ttha tein zohkhenh a si ti a langhter. Cun 300 mA cm−2 a sang deuhmi current density zong kan i zuam i 58 h a dihlak in fek tein um khawhnak kan hmuh, 46 h hnu ah AEM cu a thar in kan thlen. A cunglei hlathlainak nih hin catalyst a fekmi a langhter i hmailei ah a tthawng deuhmi AEMs sernak a herhnak kha fiang tein a langhter i cu nih cun riantuannak ah a ttha bikmi a tu lio density ah pehzulh tein AA chuah khawhnak ding caah MEA caan sau a fekmi a tthanchoter.
Kan MEA riantuan ning cungah hram bunh in, substrate rawl peknak, electrolysis, neutralization, le separation units (Supplementary Fig. 37) telh in AA chuah khawhnak tling tein kan chuahpi. Alkaline electrolyte electrocatalytic carboxylate chuahnak model55 hmangin system i sipuazi lei ah a tthatnak zohfelnak caah a hmasa riantuan ning hlathlainak tuah a si. Hi kongah, man ah tangka, riantuannak le thilri (Fig. 7a le Supplementary Fig. 38) aa tel, cun tangka hmuhmi cu AA le H2 chuahnak in a ra. TEA hmuhmi nih a langhter mi cu kan riantuannak dirhmun tangah (a tu lio 300 mA cm-2, cell voltage 1.76 V, FE 82%), a dihmi dihlak le hmuhmi cu US$2429 le US$2564 an si, AA chuahmi ton khat ah US$135 hlawknak ah aa thleng (a tawinak caah Supplement Note 9 zoh).
a AA electrochemical tuahsernak dihlak man cu FE 82%, current density 300 mA cm−2, le cell voltage 1.76 V he a hrampi thil sining tangah a si. b FE le c current density caah a dihmi pathum hna i sensitivity hlathlainak. Sensitivity hlathlainak ah, hlathlainak tuahmi parameters lawng kha an i thleng i a dang parameters pawl cu TEA model cung ah hram bunh in aa thleng lomi in an chiah hna. d FE le current density aa dangmi nih AA electrosynthesis hlawknak le Ni(OH)2-NS le NiV-LDH-NS hmannak hlawknak cungah a chuahpimi thil, cell voltage cu 1.76 V ah aa thleng lomi in chiah a si tiah ruah ahcun. a–d caah luhternak data cu raw data file ah pek a si.
Hi ruahnak cungah hram bunh in, AA electrosynthesis hlawknak cung ah FE le current density nih a chuahpimi thlennak kha kan hlathlai chin. AA FE ah hlawknak cu a tlawm tuk ti kan hmuh, zeicahtiah FE a zor tikah riantuannak man ah tampi a karh, cucaah a dihlak in man kha tampi in a karhter (Figure 7b). Atu lio tlawmtam kong he pehtlai in, a tu lio tlawmtam (>200 mA cm-2) nih tangka hmannak le sehzung saknak man tlawmternak ah a bawmh, a bik in electrolytic cell area tlawmternak in, cucaah hlawknak karhternak ah a bawmh (Figure 7c). A tu lio density he tahchunh ahcun, FE nih hlawknak ah a biapi deuhmi thlennak a chuahpi. FE le current density nih hlawknak cungah a chuahpimi thlennak kha langhternak in, hlawknak hmuh khawhnak ding caah industry he aa pehtlaimi current densities (>200 mA cm-2) ah FE sang (>60%) hmuh a biapitnak kha fiang tein kan hmuh. AA FE man a sang tuk caah, NiV-LDH-NS he thlennak phunglam cu 100-500 mA cm−2 (pentagram dots; Figure 7d) karlak ah a ttha peng. Sihmanhsehlaw, Ni(OH)2-NS caah, FE kha a sangmi current density (>200 mA cm−2) ah tlawmternak nih a ttha lomi thil a chuahter (circles; Figure 7d), a sangmi current density ah a sangmi FE a ngeimi catalysts a biapitnak kha a langhter.
Capital le riantuannak man tlawmternak ah catalysts a biapitnak lengah, kan TEA zohfelnak nih hlawknak cu lam pahnih in tthanchoter chin khawh a si tiah a langhter. Pakhatnak cu potassium sulfate (K2SO4) kha market ah neutralization unit in a chuakmi thil pakhat in zuar tti ding a si, asinain US$828/t AA-1 (Supplementary Note 9) hmuh khawhnak ding caah a si. Pahnihnak cu thilri hman tthannak asiloah a man a fawi deuhmi AA tthennak thiamnak (neutralization le tthennak unit hna caah a dang) sernak telh in thil sernak thiamnak kha ttha deuh in sersiam ding a si. A tu hmanmi acid-base thlennak kalning nih thilri man sang a chuahter khawh (cucu 85.3% ah a tam bik a si), cu chung ah 94% cu cyclohexanone le KOH ($2069/t AA-1; Figure 7a) ruangah a si, asinain a cunglei ah kan chim cang bantukin, kalning cu a dihlak in hlawknak a chuahpi rih. KOH le a thlen lomi cyclohexanone hmuh ṭhannak caah a sang deuhmi lam hna in thilri man kha tlawmter chin khawh a si lai tiah ruahnak kan cheuh, cu hna cu KOH14 tling tein hmuh ṭhannak caah electrodialysis tibantuk an si (electrodialysis hmangin US$1073/t AA-1 man tuak a si; ​​Supplementary Note 9).
A tawinak in chim ahcun, Ni(OH)2 nanosheets chungah V luhternak in a sangmi current density ah aluminium atom electrolysis tthatnak sangpi kan hmuh. 1.5-1.9 VRHE a kau ngaimi le 170 mA cm−2 a sangmi tthawnnak tangah, NiV-LDH-NS cung i AA FE cu 83-88% a phan, OER cu 3% tiang ttha tein a kham. V remhnak nih Ni2+ kha Ni3+x ah tlawmternak a bawmh i cyclohexanone laknak kha a ṭhanchoter. Hneksaknak le ruahnak data nih a langhter mi cu, a thawhtermi remhthannak nih cyclohexanone oxidation caah a tu lio a tlawmter i COR RDS cu remhthannak in Cα − H scission aa telmi dehydrogenation ah a thlen, cu lio ah cyclohexanone a tthanchomi laknak nih OER a kham. MEA sernak nih 300 mA cm−2 a simi riantuannak tthawnnak ah pehzulh tein AA chuah khawhnak, 82% AA tthatnak record, le 1536 μmol cm−2 h−1 chuah khawhnak a hmuh. Suimilam 50 chung hneksaknak nih NiV-LDH-NS cu MEA ah AA FE sang a ngeih khawh caah a fekmi dirhmun a ngei ti a langhter (200 mA cm−2 ah suimilam 60 chung > 80%; 300 mA cm−2 ah suimilam 58 chung > 70%). Industry lei ah a ttha bikmi current densities ah caan saupi fek tein um khawhnak ding caah a tthawng deuhmi AEMs ser a herh ti kha hngalh a herh. Cun, TEA nih AA chuah khawhnak caah lehrulhnak strategy hna i sipuazi ṭhatnak le man tlawmternak caah rianṭuannak sang a ngeimi catalysts le a sangmi thleidannak thiamnak hna a biapitnak kha a langhter.