Amorphous catalysts,thanks to their uniquely coordinated unsaturated properties and abundance of defect sites,tend to possess higher activity and selectivity than their crystalline counterparts.In this work,we report ...Amorphous catalysts,thanks to their uniquely coordinated unsaturated properties and abundance of defect sites,tend to possess higher activity and selectivity than their crystalline counterparts.In this work,we report a facile and general solventcontrolled precipitation method to prepare hybrids of graphene oxide(GO)supporting amorphous metal hydroxide[A-M(OH)_(x)/GO,M=Cu,Co,and Mn],which provides us with tangible materials to study the structure–performance relationship of various amorphous oxides.The systematic investigation of A-Cu(OH)_(2)/GO by coupling ex situ/in situ characteristic techniques with electrochemical studies reveals that electrocatalytic activity and selectivity toward a two-electron oxygen reduction reaction(ORR)is highly dependent on the coordinated Cu catalytic sites and the disordered structure of A-Cu(OH)_(2).In situ X-ray absorption near-edge structure(XANES)and density functional theory(DFT)calculation verify that the degree of OH*poisoning(ΔG0 OH*)tuned by three-OH-coordinated Cu sites in amorphous structures plays a crucial role in selective catalysis of ORR for H_(2)O_(2) production.The optimized A-Cu(OH)_(2)/GO shows superior activity and high selectivity(~95%)toward H_(2)O_(2),as demonstrated by a zinc–air battery capable of on-site H_(2)O_(2) production with a rate as high as 3401.5 mmol h^(−1) g^(−1).展开更多
基金the Natural Science Foundation of Fujian Province,China(grant no.2020J05079)the National Natural Science Foundation of China(grant nos.21875253,21701175,and 21703248)+1 种基金CAS-Commonwealth Scientific and Industrial Research Organization(CSIRO)Joint Research Projects(no.121835KYSB20200039)the Scientific Research and Equipment Development Project of CAS(no.YJKYYQ20190007).
文摘Amorphous catalysts,thanks to their uniquely coordinated unsaturated properties and abundance of defect sites,tend to possess higher activity and selectivity than their crystalline counterparts.In this work,we report a facile and general solventcontrolled precipitation method to prepare hybrids of graphene oxide(GO)supporting amorphous metal hydroxide[A-M(OH)_(x)/GO,M=Cu,Co,and Mn],which provides us with tangible materials to study the structure–performance relationship of various amorphous oxides.The systematic investigation of A-Cu(OH)_(2)/GO by coupling ex situ/in situ characteristic techniques with electrochemical studies reveals that electrocatalytic activity and selectivity toward a two-electron oxygen reduction reaction(ORR)is highly dependent on the coordinated Cu catalytic sites and the disordered structure of A-Cu(OH)_(2).In situ X-ray absorption near-edge structure(XANES)and density functional theory(DFT)calculation verify that the degree of OH*poisoning(ΔG0 OH*)tuned by three-OH-coordinated Cu sites in amorphous structures plays a crucial role in selective catalysis of ORR for H_(2)O_(2) production.The optimized A-Cu(OH)_(2)/GO shows superior activity and high selectivity(~95%)toward H_(2)O_(2),as demonstrated by a zinc–air battery capable of on-site H_(2)O_(2) production with a rate as high as 3401.5 mmol h^(−1) g^(−1).
