Unravelling the roles of alkali-metal cations for the enhanced oxygen evolution reaction in alkaline media
Unravelling the roles of alkali-metal cations for the enhanced oxygen evolution reaction in alkaline media
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DOI：
10.1016/j.apcatb.2021.119981
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发表时间：
2021-02-26
影响因子：
22.1
通讯作者：
Chuang, Po-Ya Abel
中科院分区：
文献类型：
--
作者：
del Rosario, Julie Anne D.;Li, Guangfu;Chuang, Po-Ya Abel
研究了碱金属阳离子对碱性析氧反应的影响，分析了碱金属阳离子对碱性析氧反应的影响。电化学测试结果表明，由于专一性吸附的OHad中间体与非专一性吸附的AM（ad）（+）之间的相互作用强度不同，使得IrOx和NiCo 2 O3上的OER活性均按Li+ < Na+ < Cs+ < K+的顺序增加。特别是，K+打破了吸附质的线性标度关系的限制，并使晶格氧介导的机制，导致活性增强。在此基础上，提出了用不同AM元素如Li、Na和K修饰Ir-Co氧化物的新策略。K辅助的Ir0.6Co0.4非晶氧化物表现出出色的OER性能，即在10 mA cm（-2）下的290 mV过电位（无欧姆校正）和36.9 mV dec（-1）动力学Tafel斜率。钾的氧化物改性对其上级性能起着至关重要的作用，这突出了界面工程对促进电子转移反应的重要性。
The electrical double layer (EDL) structure and interfacial interactions are studied to illustrate the influence of alkali metal (AM) cations on alkaline oxygen evolution reaction (OER). The electrochemical measurements show that the OER activity both on IrOx and NiCo2O3 increases in the sequence of Li+ < Na+ < Cs+ < K+ mainly due to the various interaction strength of specifically adsorbed OHad intermediates and non-specifically adsorbed AM(ad)(+) in the EDL. In particular, K+ breaks the limitation of the adsorbate's linear scaling relation and enables a lattice-oxygen-mediated mechanism, resulting in activity enhancement. Further, based on our investigation, new strategies are proposed to synthesize Ir-Co oxide with modifications of various AM elements, such as Li, Na and K. The K-assisted Ir0.6Co0.4 amorphous oxide exhibits outstanding OER performance, i.e. 290 mV overpotential (without ohmic correction) at 10 mA cm(-2), and 36.9 mV dec(-1) kinetic Tafel slope. The oxide modification with potassium plays a crucial role for its superior performance, which highlights the importance of the interfacial engineering to facilitate the electron transfer reactions.