Spin-Polarization Strategy for Enhanced Acidic Oxygen Evolution Activity
Li Ling1, Zhou Jing2, Wang Xiao3, Gracia Jose4, Valvidares Manuel5, Ke, Jia1, Fang Miaomiao1, Shen Chenqi1, Chen Jin-Ming6, Chang Yu-Chung6, Pao Chih-Wen6, Hsu Su-Yang6, Lee Jyh-Fu6, Ruotolo Antonio7, Chin Yiying8, Hu Zhiwei3*(胡志伟), Huang Xiaoqing9*(黄小青), Shao Qi1* (邵琪)
Adv. Mater. 2023, 2302966
Abstract：Spin-polarization is known as a promising way to promote the anodic oxygen evolution reaction (OER), since the intermediates and products endow spin-dependent behaviors, yet it is rarely reported for ferromagnetic catalysts toward acidic OER practically used in industry. Herein, the first spin-polarization-mediated strategy is reported to create a net ferromagnetic moment in antiferromagnetic RuO2 via dilute manganese (Mn2+) (S = 5/2) doping for enhancing OER activity in acidic electrolyte. Element-selective X-ray magnetic circular dichroism reveals the ferromagnetic coupling between Mn and Ru ions, fulfilling the Goodenough-Kanamori rule. The ferromagnetism behavior at room temperature can be well interpreted by first principles calculations as the interaction between the Mn2+ impurity and Ru ions. Indeed, Mn-RuO2 nanoflakes exhibit a strongly magnetic field enhanced OER activity, with the lowest overpotential of 143 mV at 10 mA cmgeo-2 and negligible activity decay in 480 h stability (vs 200 mV/195 h without magnetic field) as known for magnetic effects in the literature. The intrinsic turnover frequency is also improved to reach 5.5 s-1 at 1.45 VRHE. This work highlights an important avenue of spin-engineering strategy for designing efficient acidic oxygen evolution catalysts.
链接：//onlinelibrary.wiley.com/doi/10.1002/adma.202302966
