Electrocatalysts with high activity and long-term durability are vital toward large-scale hydrogen pro-duction from electrocatalytic water splitting.Here,the self-supported electrode(FeO_(χ)H_(y)@Ni_(3)B/NF)with hier...Electrocatalysts with high activity and long-term durability are vital toward large-scale hydrogen pro-duction from electrocatalytic water splitting.Here,the self-supported electrode(FeO_(χ)H_(y)@Ni_(3)B/NF)with hierarchical heterostructure was simply prepared by using Ni_(3)B chunks grown on nickel foam as sub-strate to in situ form vertical FeO_(χ)H_(y)nanosheets.Such hybrid shows efficient oxygen evolution reaction activity with overpotentials as low as 267 and 249 mV at 100 mA cm^(-2)in 1 M KOH solution and 30 wt%KOH solution,respectively.Meanwhile,it also exhibits excellent catalytic stability,sustaining catalysis at 500 mA cm^(-2)in 1 M KOH solution for 200 h,and even for 200 h at 1000 mA cm^(-2)in 30 wt%KOH solution.Further experimental results reveal that the FeO_(χ)H_(y)@Ni_(3)B/NF is endowed with superhydrophilic and superaerophobic surface properties,which not only provide more mass transport channels,as well as facilitated the diffusion of reaction intermediates and gas bubbles.Also,it holds faster reaction kinetics,more accessible active sites and accelerated electron transfer rates due to strong synergistic interactions attheheterogeneous interface.展开更多
The development of active yet stable catalysts for oxygen reduction reaction(ORR)is still a major issue for the extensive permeation of fuel cells into everyday technology.While nanostructured Pt catalysts are to date...The development of active yet stable catalysts for oxygen reduction reaction(ORR)is still a major issue for the extensive permeation of fuel cells into everyday technology.While nanostructured Pt catalysts are to date the best available systems in terms of activity,the same is not true for stability,particularly under operating conditions.In this work,Pt_(Х)Y alloy nanoparticles are proposed as active and durable electrocatalysts for ORR.Pt_(Х)Y nanoalloys are synthesized and further optimized by laser ablation in liquid followed by laser fragmentation in liquid.The novel integrated laser-assisted methodology succeeded in producing Pt_(Х)Y nanoparticles with the ideal size(<10 nm)of commercial Pt catalysts,yet resulting remarkably more active with E_(1/2)=0.943 V vs.RHE,specific activity=1095μA cm^(-2) and mass activity>1000 A g^(-1).At the same time,the nanoalloys are embedded in a fine Pt oxide matrix,which allows a greater stability of the catalyst than the commercial Pt reference,as directly verified on a gas diffusion electrode.展开更多
基金supported by the National Natural Science Foundation of China (12234018,52101256,51872115)
文摘Electrocatalysts with high activity and long-term durability are vital toward large-scale hydrogen pro-duction from electrocatalytic water splitting.Here,the self-supported electrode(FeO_(χ)H_(y)@Ni_(3)B/NF)with hierarchical heterostructure was simply prepared by using Ni_(3)B chunks grown on nickel foam as sub-strate to in situ form vertical FeO_(χ)H_(y)nanosheets.Such hybrid shows efficient oxygen evolution reaction activity with overpotentials as low as 267 and 249 mV at 100 mA cm^(-2)in 1 M KOH solution and 30 wt%KOH solution,respectively.Meanwhile,it also exhibits excellent catalytic stability,sustaining catalysis at 500 mA cm^(-2)in 1 M KOH solution for 200 h,and even for 200 h at 1000 mA cm^(-2)in 30 wt%KOH solution.Further experimental results reveal that the FeO_(χ)H_(y)@Ni_(3)B/NF is endowed with superhydrophilic and superaerophobic surface properties,which not only provide more mass transport channels,as well as facilitated the diffusion of reaction intermediates and gas bubbles.Also,it holds faster reaction kinetics,more accessible active sites and accelerated electron transfer rates due to strong synergistic interactions attheheterogeneous interface.
基金the P-DISC Grant PROMETEO(project number:P-DiSC#03NExuS_BIRD2021-UNIPD)DYNAMO(project number:P-P-DiSC#01BIRD2020-UNIPD)the financial support of the Fellowship in Applied Electrochemistry 2020。
文摘The development of active yet stable catalysts for oxygen reduction reaction(ORR)is still a major issue for the extensive permeation of fuel cells into everyday technology.While nanostructured Pt catalysts are to date the best available systems in terms of activity,the same is not true for stability,particularly under operating conditions.In this work,Pt_(Х)Y alloy nanoparticles are proposed as active and durable electrocatalysts for ORR.Pt_(Х)Y nanoalloys are synthesized and further optimized by laser ablation in liquid followed by laser fragmentation in liquid.The novel integrated laser-assisted methodology succeeded in producing Pt_(Х)Y nanoparticles with the ideal size(<10 nm)of commercial Pt catalysts,yet resulting remarkably more active with E_(1/2)=0.943 V vs.RHE,specific activity=1095μA cm^(-2) and mass activity>1000 A g^(-1).At the same time,the nanoalloys are embedded in a fine Pt oxide matrix,which allows a greater stability of the catalyst than the commercial Pt reference,as directly verified on a gas diffusion electrode.
