Creating vacancy is often highly effective in enhancing the hydrogen evolution performance of transition metal-based catalysts.Vacancy-rich Ni nanosheets have been fabricated via topochemical formation of two-dimentio...Creating vacancy is often highly effective in enhancing the hydrogen evolution performance of transition metal-based catalysts.Vacancy-rich Ni nanosheets have been fabricated via topochemical formation of two-dimentional(2D)Ni_(2)B on graphene precursor followed by boron leaching.Anchored on graphene,a few atomic layered Ni_(2)B nanosheets are first obtained by reduction and annealing.Large number of atomic vacancies are then generated in the Ni_(2)B layer via leaching boron atoms.When used for hydrogen evolution reaction(HER),the vacancy-rich Ni/Ni(OH)_(2 )heterostructure nanosheets demonstrate remarkable performance with a low overpotential of 159 mV at a current density of 10 mA·cm^(−2) in alkaline solution,a dramatic improvement over 262 mV of its precursor.This enhancement is associated with the formation of vacancies which introduce more active sites for HER along Ni/Ni(OH)_(2) heterointerfaces.This work offers a facile and universal route to introduce vacancies and improve catalytic activity.展开更多
基金Acknowledgements Z.H.acknowledges support under the Australian Research Council’s Future Fellowship(No.FT190100658)This work is partially supported by the Australian Research Council(ARC)through a Discovery project(No.DP180101453).
文摘Creating vacancy is often highly effective in enhancing the hydrogen evolution performance of transition metal-based catalysts.Vacancy-rich Ni nanosheets have been fabricated via topochemical formation of two-dimentional(2D)Ni_(2)B on graphene precursor followed by boron leaching.Anchored on graphene,a few atomic layered Ni_(2)B nanosheets are first obtained by reduction and annealing.Large number of atomic vacancies are then generated in the Ni_(2)B layer via leaching boron atoms.When used for hydrogen evolution reaction(HER),the vacancy-rich Ni/Ni(OH)_(2 )heterostructure nanosheets demonstrate remarkable performance with a low overpotential of 159 mV at a current density of 10 mA·cm^(−2) in alkaline solution,a dramatic improvement over 262 mV of its precursor.This enhancement is associated with the formation of vacancies which introduce more active sites for HER along Ni/Ni(OH)_(2) heterointerfaces.This work offers a facile and universal route to introduce vacancies and improve catalytic activity.
