Toward enhanced alkaline hydrogen electrocatalysis with transition metal-functionalized nitrogen-doped carbon supports
Publication Name
Chinese Journal of Catalysis
Abstract
Superior catalyst supports are crucial to developing advanced electrocatalysts toward heterogeneous catalytic reactions. Herein, we systematically investigate the role of transition metal-functionalized N-doped carbon nanosheets (M-N-C, M = Mn, Fe, Co, Ni, Cu, Mo, and Ag) as the multifunctional electrocatalyst supports toward hydrogen evolution/oxidation reactions (HER/HOR) in alkaline media. The results demonstrate that all the M-N-C nanosheets, except Cu-N-C and Ag-N-C, can promote the alkaline HER/HOR electrocatalytic activity of Pt by accelerating the sluggish Volmer step, among which Mn plays a more significant role. Analyses reveal that the promotion effect of M-N-C support is closely associated with the electronegativity of the metal dopants and the relative filling degree of their d-orbitals. For one, the metal dopant in M-N-C with smaller electronegativity would provide more electrons to oxygen and hence tune the electronic structure of Pt via the M-O-Pt bonds at the interface. For another, the transition metal in M-N4 moieties with more empty d orbitals would hybridize with O 2p orbitals more strongly that promotes the adsorption of water/hydroxyl species. The results demonstrate the conceptual significance of multifunctional supports and would inspire the future development of advanced electrocatalysts.
Open Access Status
This publication is not available as open access
Volume
43
Issue
5
First Page
1351
Last Page
1359
Funding Number
YJ20200160
Funding Sponsor
Australian Research Council