Metal/carbon nanocomposites have shown great potential as high-performance,low-cost electrocatalysts owing largely to their unique metal-support interactions.These nanocomposites are typically prepared by conventional...Metal/carbon nanocomposites have shown great potential as high-performance,low-cost electrocatalysts owing largely to their unique metal-support interactions.These nanocomposites are typically prepared by conventional pyrolysis that is tedious and energy-intensive.Herein,we report the ultrafast preparation of cobalt/carbon nanocomposites by magnetic induction heating(MIH)of metal organic frameworks within seconds under an inert atmosphere.The resulting samples consist of cobalt nanoparticles encapsulated within defective carbon shells,and effectively catalyze oxygen evolution reaction(OER)in alkaline media.Among the series,the sample prepared at 400 A for 10 s exhibits the best OER performance,needing a low overpotential of+308 mV to reach the current density of 10 mA cm^(−2),along with excellent stability,and even outperforms commercial RuO_(2) at high overpotentials.This is ascribed to the charge transfer between the carbon scaffold and metal nanoparticles.Operando X-ray absorption spectroscopy measurements show that the electrochemically produced CoOOH species is responsible for the high electrocatalytic performance.The results highlight the unique potential of MIH in the development of effective nanocomposite catalysts for electrochemical energy technologies.展开更多
基金National Science Foundation(CHE-1900235 and CHE-2003685)TEM,XPS,and Raman studies were conducted as part of a user project at the National Center for Electron Microscopy and Molecular Foundry,Lawrence Berkeley National Laboratory,which is supported by the Office of Science,Office of Basic Energy Sciences,of the U.S.Department of Energy under Contract No.DE-AC02-05CH11231+1 种基金XAS experiments were performed at the Stanford Synchrotron Radiation Lightsource(SSRL),which is supported by the U.S.Department of Energy,Office of Science,Office of Basic Energy Sciences under Contract No.DE-AC02-76SF00515Q.M.L.acknowledges the ECS Joseph W.Richards Summer Fellowship for funding support and the support of a Grant-in-Aid of Research(G20211001-639)from the National Academy of Sciences,administered by Sigma Xi,The Scientific Research Society.
文摘Metal/carbon nanocomposites have shown great potential as high-performance,low-cost electrocatalysts owing largely to their unique metal-support interactions.These nanocomposites are typically prepared by conventional pyrolysis that is tedious and energy-intensive.Herein,we report the ultrafast preparation of cobalt/carbon nanocomposites by magnetic induction heating(MIH)of metal organic frameworks within seconds under an inert atmosphere.The resulting samples consist of cobalt nanoparticles encapsulated within defective carbon shells,and effectively catalyze oxygen evolution reaction(OER)in alkaline media.Among the series,the sample prepared at 400 A for 10 s exhibits the best OER performance,needing a low overpotential of+308 mV to reach the current density of 10 mA cm^(−2),along with excellent stability,and even outperforms commercial RuO_(2) at high overpotentials.This is ascribed to the charge transfer between the carbon scaffold and metal nanoparticles.Operando X-ray absorption spectroscopy measurements show that the electrochemically produced CoOOH species is responsible for the high electrocatalytic performance.The results highlight the unique potential of MIH in the development of effective nanocomposite catalysts for electrochemical energy technologies.
