Electrocatalytic reduction of nitrate(NO3−)to valuable organonitrogen compounds beyond ammonia is a promising strategy for mitigating the humancaused unbalance of the global nitrogen cycle.Herein,we present an electro...Electrocatalytic reduction of nitrate(NO3−)to valuable organonitrogen compounds beyond ammonia is a promising strategy for mitigating the humancaused unbalance of the global nitrogen cycle.Herein,we present an electrochemical strategy for synthesizing cyclohexanone oxime(CHO),an important feedstock in nylon-6 production through hydrogenative coupling of NO_(3)^(−)and cyclohexanone(CYC)using a rutile titanium dioxide(R-TiO_(2))catalyst under ambient conditions.The CHO productivity achieved 127.3μmol cm^(−2) h^(−1) with a high Faradaic efficiency(FE)of 68.2%at a current density of 30 mA cm^(−2).Moreover,the yield of CHO reached 98.2%.We demonstrated that the electrosynthesis of CHO operated through a tandem reaction mechanism involving the in situ generation of hydroxylamine(NH2OH)from NO_(3)^(−) reduction,followed by a spontaneous nucleophilic addition–elimination reaction between NH2OH and CYC.Additionally,we revealed that R-TiO_(2) exhibited a superior scaling relation with a high NH2OH generation rate and excellent CYC adsorption ability,which promoted CHO production.This electrochemical strategy was also effective for the synthesis of different oximes.Finally,we designed a coupling reaction system to realize the simultaneous production of CHO and CYC by combining cathodic NO3−reduction and anodic cyclohexane oxidation,demonstrating a greener and more economical approach.展开更多
基金supported by the National Natural Science Foundation of China(grant nos.22090031,22108008,22288102,and 22302006)the Young Elite Scientist Sponsorship Program by Chinese Association for Science and Technology(CAST,grant no.2021QNRC001)+1 种基金the Fundamental Research Funds for the Central Universities,Chongqing,China(grant no.buctrc202011)the National Funded Postdoctoral Researchers Program(grant no.GZB20230049).
文摘Electrocatalytic reduction of nitrate(NO3−)to valuable organonitrogen compounds beyond ammonia is a promising strategy for mitigating the humancaused unbalance of the global nitrogen cycle.Herein,we present an electrochemical strategy for synthesizing cyclohexanone oxime(CHO),an important feedstock in nylon-6 production through hydrogenative coupling of NO_(3)^(−)and cyclohexanone(CYC)using a rutile titanium dioxide(R-TiO_(2))catalyst under ambient conditions.The CHO productivity achieved 127.3μmol cm^(−2) h^(−1) with a high Faradaic efficiency(FE)of 68.2%at a current density of 30 mA cm^(−2).Moreover,the yield of CHO reached 98.2%.We demonstrated that the electrosynthesis of CHO operated through a tandem reaction mechanism involving the in situ generation of hydroxylamine(NH2OH)from NO_(3)^(−) reduction,followed by a spontaneous nucleophilic addition–elimination reaction between NH2OH and CYC.Additionally,we revealed that R-TiO_(2) exhibited a superior scaling relation with a high NH2OH generation rate and excellent CYC adsorption ability,which promoted CHO production.This electrochemical strategy was also effective for the synthesis of different oximes.Finally,we designed a coupling reaction system to realize the simultaneous production of CHO and CYC by combining cathodic NO3−reduction and anodic cyclohexane oxidation,demonstrating a greener and more economical approach.
