摘要
Heteroatomic substitution and vacancy engineering of spinel oxides can theoretically optimize the oxygen evolution reaction(OER)through charge redistribution and d-band center modification but still remain a great challenge in both the preparation and catalytic mechanism.Herein,we proposed a novel and efficient Ar-plasma(P)-assisted strategy to construct heteroatom Mo-substituted and oxygen vacancies enriched hierarchical spinel Co_(3)O_(4)porous nanoneedle arrays in situ grown on carbon cloth(denoted P-Mo-Co_(3)O_(4)@CC)to improve the OER performance.Ar-plasma technology can efficiently generate vacancy sites at the surface of hydroxide,which induces the anchoring of Mo anion salts through electrostatic interaction,finally facilitating the substitution of Mo atoms and the formation of oxygen vacancies on the Co_(3)O_(4)surface.The P-Mo-Co_(3)O_(4)@CC affords a low overpotential of only 276 mV at 10 mA cm^(−2)for the OER,which is 58 mV superior to that of Mo-free Co_(3)O_(4)@CC and surpasses commercial RuO_(2)catalyst.The robust stability and satisfactory selectivity(nearly 100%Faradic efficiency)of P-Mo-Co_(3)O_(4)@CC for the OER are also demonstrated.Theoreti-cal studies demonstrate that Mo with variable valance states can efficiently regulates the atomic ratio of Co^(3+)/Co^(2+)and increases the number of oxygen vacancies,thereby inducing charge redistribution and tuning the d-band center of Co_(3)O_(4),which improve the adsorption energy of oxygen intermediates(e.g.,*OOH)on P-Mo-Co_(3)O_(4)@CC during OER.Furthermore,the two-electrode OER//HER electrolyzer equipped with P-Mo-Co_(3)O_(4)@CC as anode displays a low operation potential of 1.54 V to deliver a current density of 10 mA cm^(−2),and also exhibits good reversibility and anticurrent fluctuation ability under simulated real energy supply conditions,demonstrating the great potential of P-Mo-Co_(3)O_(4)@CC in water electrolysis.
基金
National Natural Science Foundation of China,Grant/Award Numbers:21875112,22109073
Natural Science Foundation of Jiangsu Province,Grant/Award Number:BK20221321。
作者简介
contributed equally:Yujie Huang;contributed equally:Meng Li;Correspondence author:Yawen Tang,Jiangsu Key Laboratory of New Power Batteries,School of Chemistry and Materials Science,Jiangsu Collaborative Innovation Centre of Biomedical Functional Materials,Nanjing Normal University,210023 Nanjing,China.Email:tangyawen@njnu.edu.cn;Correspondence author:Gengtao Fu,Jiangsu Key Laboratory of New Power Batteries,School of Chemistry and Materials Science,Jiangsu Collaborative Innovation Centre of Biomedical Functional Materials,Nanjing Normal University,210023 Nanjing,China.Email:gengtaofu@njnu.edu.cn,http://orcid.org/0000-0003-0411-645X。
