Zhou Chenhui, Chen Xiao, Liu Shuo, Han Ying, Meng Haibing, Jiang Qinyuan, Zhao Siming, Wei Fei, Sun Jie, Tan Ting, Zhang Rufan
Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China.
Key Laboratory for Green Chemical Technology of Ministry of Education, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China.
J Am Chem Soc. 2022 Feb 16;144(6):2694-2704. doi: 10.1021/jacs.1c11675. Epub 2022 Feb 1.
The development of high-efficiency and durable bifunctional electrocatalysts for both the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is critical for the widespread application of rechargeable zinc-air (Zn-air) batteries. This calls for rational screening of targeted ORR/OER components and precise control of their atomic and electronic structures to produce synergistic effects. Here, we report a Mn-doped RuO (Mn-RuO) bimetallic oxide with atomic-scale dispersion of Mn atoms into the RuO lattice, which exhibits remarkable activity and super durability for both the ORR and OER, with a very low potential difference (Δ) of 0.64 V between the half-wave potential of ORR () and the OER potential at 10 mA cm () and a negligible decay of and after 250 000 and 30 000 CV cycles for ORR and OER, respectively. Moreover, Zn-air batteries using the Mn-RuO catalysts exhibit a high power density of 181 mW cm, low charge/discharge voltage gaps of 0.69/0.96/1.38 V, and ultralong lifespans of 15 000/2800/1800 cycles (corresponding to 2500/467/300 h operation time) at a current density of 10/50/100 mA cm, respectively. Theoretical calculations reveal that the excellent performances of Mn-RuO is mainly due to the precise optimization of valence state and -band center for appropriate adsorption energy of the oxygenated intermediates.
开发用于氧还原反应（ORR）和析氧反应（OER）的高效耐用双功能电催化剂对于可充电锌空气（Zn-air）电池的广泛应用至关重要。这需要合理筛选目标ORR/OER组分并精确控制其原子和电子结构以产生协同效应。在此，我们报道了一种Mn掺杂的RuO（Mn-RuO）双金属氧化物，其中Mn原子以原子尺度分散到RuO晶格中，该双金属氧化物对ORR和OER均表现出卓越的活性和超耐久性，在ORR的半波电位（）与10 mA cm（）下的OER电位之间具有非常低的电位差（Δ），为0.64 V，并且在分别进行250000次和30000次ORR和OER的循环伏安（CV）循环后，和的衰减可忽略不计。此外，使用Mn-RuO催化剂的锌空气电池在10/50/100 mA cm的电流密度下分别表现出181 mW cm的高功率密度、0.69/0.96/1.38 V的低充/放电电压间隙以及15000/2800/1800次循环（分别对应2500/467/300 h的运行时间）的超长寿命。理论计算表明，Mn-RuO的优异性能主要归因于价态和带中心的精确优化，以实现含氧中间体的适当吸附能。
