Niu Yanli, Jiang Gang, Gong Shuaiqi, Liu Xuan, Shangguan Enbo, Li Linpo, Chen Zuofeng
Henan Engineering Research Center of Design and Recycle for Advanced Electrochemical Energy Storage Materials, School of Materials Science and Engineering, Henan Normal University, Xinxiang 453007, China; School of Chemical Science and Engineering, Tongji University, Shanghai 200092, China.
Henan Engineering Research Center of Design and Recycle for Advanced Electrochemical Energy Storage Materials, School of Materials Science and Engineering, Henan Normal University, Xinxiang 453007, China.
J Colloid Interface Sci. 2024 Feb 15;656:346-357. doi: 10.1016/j.jcis.2023.11.112. Epub 2023 Nov 19.
Designing bifunctional electrocatalysts with outstanding reactivity and durability towards the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) has remained a long-term aim for metal-air batteries. Achieving the high level of fusion between two distinct metal components to form bifunctional catalysts with optimized heterointerfaces and well-defined morphology holds noteworthy implications in the enhancement of electrocatalytic activity yet challenging. Herein, the fabrication of numerous heterointerfaces of CoN/MnO is successfully realized within ultrathin carbon nanosheets via a feasible self-templating synthesis strategy. Experimental results and theoretic calculations verify that the interfacial electron transfer from CoN to MnO at the heterointerface engenders an ameliorated charge transfer velocity, finely tuned energy barriers concerning reaction intermediates and ultimately accelerated reaction kinetics. The as-prepared CoN/MnO@NC demonstrates exceptional bifunctional catalytic performance, excelling in both OER and ORR showcasing a low reversible overpotential of 0.69 V. Furthermore, rechargeable liquid and quasi-solid-state flexible Zn-air batteries employing CoN/MnO@NC as the air-cathode deliver remarkable endurance and elevated power density, registering values of 153 and 116 mW cm respectively and exceeding Pt/C + RuO counterparts and those reported in literature. Deeply exploring the effect of electron-accumulated heterointerfaces on catalytic activity would contribute wisdom to the development of bifunctional electrocatalysts for rechargeable metal-air batteries.
设计对氧还原反应（ORR）和析氧反应（OER）具有出色反应活性和耐久性的双功能电催化剂一直是金属空气电池的长期目标。实现两种不同金属组分之间的高度融合以形成具有优化异质界面和明确形态的双功能催化剂，对提高电催化活性具有重要意义，但仍具有挑战性。在此，通过一种可行的自模板合成策略，在超薄碳纳米片中成功实现了大量CoN/MnO异质界面的制备。实验结果和理论计算证实，在异质界面处从CoN到MnO的界面电子转移产生了改善的电荷转移速度，微调了与反应中间体相关的能垒，并最终加速了反应动力学。所制备的CoN/MnO@NC表现出优异的双功能催化性能，在OER和ORR中均表现出色，具有0.69 V的低可逆过电位。此外，采用CoN/MnO@NC作为空气阴极的可充电液体和准固态柔性锌空气电池具有出色的耐久性和较高的功率密度，分别达到153和116 mW cm，超过了Pt/C + RuO对应物以及文献报道的值。深入探索电子积累异质界面对催化活性的影响将为可充电金属空气电池双功能电催化剂的开发提供智慧。
