The electrochemical carbon dioxide reduction reaction(CO_(2)RR)is considered as one of the sustainable and economical strategies for carbon utilization to effectively control the greenhouse effect and alleviate the ra...The electrochemical carbon dioxide reduction reaction(CO_(2)RR)is considered as one of the sustainable and economical strategies for carbon utilization to effectively control the greenhouse effect and alleviate the rapid consumption of fossil fuels.In this work,metal–organic framework(MOF)-derived Ce-doped Bi@C nanorod(NR)electrocatalysts are facilely prepared through the pyrolysis method.Benefitting from Ce doping,the electron density around Bi active sites increases and the Bi–Bi bond length shortens,leading to stabilized reaction intermediates,a lower energy barrier towards^(*)OCHO formation,faster electron transfer,and improved CO_(2)adsorption.As a result,Ce_(0.05)Bi_(0.95)@C NRs show desirable faradaic efficiencies(FE)of over 90%towards formate formation in a wide potential window from−0.9 to−1.9V_(vs.RHE)in an H-type cell,with the maximum value of 96.1%.Owing to the good intrinsic electrocatalytic activity,a high throughput performance of formate production is achieved with a FE of over 90%under high current density in a potential range as wide as 1100 mV,demonstrating the great potential of Ce doped Bi@C NRs for practical CO_(2)RR applications.展开更多
The design and preparation of highly efficient and durable electrocatalysts for the oxygen reduction reaction(ORR)and the oxygen evolution reaction(OER)is essential due to their applications in many green energy conve...The design and preparation of highly efficient and durable electrocatalysts for the oxygen reduction reaction(ORR)and the oxygen evolution reaction(OER)is essential due to their applications in many green energy conversion devices,such as fuel cells and rechargeable metal–air batteries.Herein,we report a Co/Co9S8 composite catalyst,which is coupled with reduced graphene oxide(rGO)and multi-walled carbon nanotubes(MWCNTs)via a combined hydrothermal reaction with a calcination method.Benefiting from the unique porous scaffold structures and synergistic interactions between rGO/MWCNT and Co/Co9S8,the electrocatalyst(Co/Co9S8/rGO/MWCNT-800)exhibits high electrochemical activity for the ORR,showing a four-electron oxygen reduction pathway with an onset potential of 0.946 V(vs.RHE)in alkaline medium.Meanwhile,the electrocatalyst shows high electrochemical stability,excellent selectivity and methanol tolerance over the commercial Pt/C.It also exhibits good overall oxygen electrode activity(ΔE=EOER,10−EORR,1/2 of 890 mV).The present work highlights a potential general strategy for developing carbon-based transition metal sulfide nanocomposites as cathodes with better performance in the ORR/OER.展开更多
基金supported by the Natural Sciences and Engineering Research Council of Canada(NSERC)through the Discovery Grant Program(RGPIN-2016-05494,RGPIN-2018-06725)+4 种基金the Discovery Accelerator Supplement Grant Program(RGPAS-2018-522651)by the New Frontiers in Research Fund-Exploration program(NFRFE-2019-00488)This research was supported by funding from the Canada First Research Excellence Fund(CFRER-2015-00001)as part of the University of Alberta’s Future Energy Systems research initiative(FES-T02-P03 and FES-T06-Q03)Y.-C.Wang acknowledges China Scholarship Council(CSC)support of NanoFAB in sample preparation and electronmicroscopy at the University of Alberta in Canada。
文摘The electrochemical carbon dioxide reduction reaction(CO_(2)RR)is considered as one of the sustainable and economical strategies for carbon utilization to effectively control the greenhouse effect and alleviate the rapid consumption of fossil fuels.In this work,metal–organic framework(MOF)-derived Ce-doped Bi@C nanorod(NR)electrocatalysts are facilely prepared through the pyrolysis method.Benefitting from Ce doping,the electron density around Bi active sites increases and the Bi–Bi bond length shortens,leading to stabilized reaction intermediates,a lower energy barrier towards^(*)OCHO formation,faster electron transfer,and improved CO_(2)adsorption.As a result,Ce_(0.05)Bi_(0.95)@C NRs show desirable faradaic efficiencies(FE)of over 90%towards formate formation in a wide potential window from−0.9 to−1.9V_(vs.RHE)in an H-type cell,with the maximum value of 96.1%.Owing to the good intrinsic electrocatalytic activity,a high throughput performance of formate production is achieved with a FE of over 90%under high current density in a potential range as wide as 1100 mV,demonstrating the great potential of Ce doped Bi@C NRs for practical CO_(2)RR applications.
基金support from the National Natural Science Foundation of China(No.21673098 and No.21871042)the Joint Program of Jilin Province and Jilin University(SXGJQY2017-1)the Jilin Provincial Science&Technology Department(20190303039SF).
文摘The design and preparation of highly efficient and durable electrocatalysts for the oxygen reduction reaction(ORR)and the oxygen evolution reaction(OER)is essential due to their applications in many green energy conversion devices,such as fuel cells and rechargeable metal–air batteries.Herein,we report a Co/Co9S8 composite catalyst,which is coupled with reduced graphene oxide(rGO)and multi-walled carbon nanotubes(MWCNTs)via a combined hydrothermal reaction with a calcination method.Benefiting from the unique porous scaffold structures and synergistic interactions between rGO/MWCNT and Co/Co9S8,the electrocatalyst(Co/Co9S8/rGO/MWCNT-800)exhibits high electrochemical activity for the ORR,showing a four-electron oxygen reduction pathway with an onset potential of 0.946 V(vs.RHE)in alkaline medium.Meanwhile,the electrocatalyst shows high electrochemical stability,excellent selectivity and methanol tolerance over the commercial Pt/C.It also exhibits good overall oxygen electrode activity(ΔE=EOER,10−EORR,1/2 of 890 mV).The present work highlights a potential general strategy for developing carbon-based transition metal sulfide nanocomposites as cathodes with better performance in the ORR/OER.
