Tailored synthesis of earth-abundant alkaline hydrogen evolution electrocatalysts,featuring optimized metal/oxide heterointerfacial structures and rapid charge-/mass-transfer characteristics,remains a significant chal...Tailored synthesis of earth-abundant alkaline hydrogen evolution electrocatalysts,featuring optimized metal/oxide heterointerfacial structures and rapid charge-/mass-transfer characteristics,remains a significant challenge in advancing water electrolysis as a viable technology for sustainable hydrogen production.Herein,we report the boride-mediated and carbon nanotubes(CNT)-scaffolded synthesis of a cobaltbased electrocatalyst that can effectively address the key factors influencing alkaline HER performance.Specifically,a cobalt foam(CF)supported composite catalyst(Co/CoO/CNT)was prepared via a threestep procedure:(1)combustion synthesis of CNT networks on a CF surface,(2)electroless plating of the boride precursor onto the surface of CNT-decorated CF,and(3)annealing treatment to induce solidphase reaction between the boride and adjacent CoO.The boride-mediated synthesis allows for the formation of abundant Co/CoO heterointerfacial boundaries,which serve as active sites for alkaline HER.The pre-growth of CNT networks enables the construction of a hierarchical mesoporous-macroporous architecture,rendering improved active site accessibility and enhanced water transport and gas release in the catalyst layer.In addition,the incorporation of conductive CNTs helps improve charge-transfer kinetics.Benefiting from these favorable attributes,the Co/CoO/CNT/CF catalyst showed excellent alkaline HER performance,requiring only 17 and 185 mV overpotentials to afford current densities of 10 and 500 mA cm^(−2),respectively,and maintaining long-term stability at high current densities up to 1000 mA cm^(−2).Furthermore,the catalyst exhibited fairly good performance in alkaline natural seawater electrolysis,enabling stable hydrogen production at 500 mA cm^(−2) for over 100 hours.展开更多
基金financially supported by NSFC(Grant No.51621001)and the National 10000-Talents Program.
文摘Tailored synthesis of earth-abundant alkaline hydrogen evolution electrocatalysts,featuring optimized metal/oxide heterointerfacial structures and rapid charge-/mass-transfer characteristics,remains a significant challenge in advancing water electrolysis as a viable technology for sustainable hydrogen production.Herein,we report the boride-mediated and carbon nanotubes(CNT)-scaffolded synthesis of a cobaltbased electrocatalyst that can effectively address the key factors influencing alkaline HER performance.Specifically,a cobalt foam(CF)supported composite catalyst(Co/CoO/CNT)was prepared via a threestep procedure:(1)combustion synthesis of CNT networks on a CF surface,(2)electroless plating of the boride precursor onto the surface of CNT-decorated CF,and(3)annealing treatment to induce solidphase reaction between the boride and adjacent CoO.The boride-mediated synthesis allows for the formation of abundant Co/CoO heterointerfacial boundaries,which serve as active sites for alkaline HER.The pre-growth of CNT networks enables the construction of a hierarchical mesoporous-macroporous architecture,rendering improved active site accessibility and enhanced water transport and gas release in the catalyst layer.In addition,the incorporation of conductive CNTs helps improve charge-transfer kinetics.Benefiting from these favorable attributes,the Co/CoO/CNT/CF catalyst showed excellent alkaline HER performance,requiring only 17 and 185 mV overpotentials to afford current densities of 10 and 500 mA cm^(−2),respectively,and maintaining long-term stability at high current densities up to 1000 mA cm^(−2).Furthermore,the catalyst exhibited fairly good performance in alkaline natural seawater electrolysis,enabling stable hydrogen production at 500 mA cm^(−2) for over 100 hours.
