Abstract
Spin engineering is recognized as a promising strategy that modulates the association between d-orbital electrons and the oxygenated species, and enhances the catalytic kinetics. However, few efforts have been made to clarify whether spin engineering could make a considerable enhancement for electrocatalytic water oxidation. Herein, we report the spin engineering of a nanocage-structured (Co,Ni)Se-2/C@FeOOH, that showed significant oxygen evolution reaction (OER) activity. Magnetization measurement presented that the (Co,Ni)Se-2/C@FeOOH sample possesses higher polarization spin number (mu(b) = 6.966 mu B/f.u.) compared with that of the (Co,Ni)Se-2/C sample (mu(b) = 6.398 mu B/f.u.), for which the enlarged spin polarization number favors the adsorption and desorption energy of the intermediate oxygenated species, as confirmed by surface valance band spectra. Consequently, the (Co,Ni)Se-2/C@FeOOH affords remarkable OER product with a low overpotential of 241 mV at a current of 10 mA cm(-2) and small Tafel slope of 44 mV dec(-1) in 1.0 mol/L KOH alkaline solution, significantly surpassing the parent (Co,Ni)Se-2/C catalyst. This work will trigger a solid step for the design of highly-efficient OER electrocatalysts. (C) 2022, Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.