Ru-based single-atomic catalysts have shown great potential application in sustainable electrochemical energy conversion/storage devices. Herein Ru single atoms anchored on the surface of MnO2 nanorods (Ru SAs@MnO2) have been successfully constructed by a facile low-temperature solid-phase reaction, which has been confirmed by X-ray adsorption spectra. The synthesized Ru SAs@MnO2 catalyst exhibits a comparable ORR performance with half-wave potential of 0.83 V and a limiting current density of 7.1 mA cm−2 to commercial Pt/C, and high OER performance with the overpotential of 320 mV at 10 mA cm−2. Theoretical calculation results indicate that Mn sites and Ru sites of Ru SAs@MnO2 act as the catalytic ORR and OER sites, respectively, and the synergistic effect between Ru SAs and MnO2 contributes to the improved catalytic performance via strong electronic interaction. When assembled zinc-air batteries, a maximum power density 230.0 mW cm−2 could be delivered at 318.5 mA cm−2.

中文翻译：

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Ru单原子和MnO2通过强电子相互作用增强氧还原/放出活性的协同效应


钌基单原子催化剂在可持续电化学能量转换/存储装置中显示出巨大的应用潜力。本文通过简单的低温固相反应成功地构建了锚定在MnO2纳米棒表面的Ru单原子（Ru SAs@MnO2），并已通过X射线吸收光谱证实。合成的 Ru SAs@MnO2 催化剂表现出与商业 Pt/C 相当的 ORR 性能，半波电位为 0.83 V，极限电流密度为 7.1 mA cm−2，并且具有高 OER 性能，10 mA 下的过电位为 320 mV厘米−2。理论计算结果表明，Ru SAs@MnO2的Mn位点和Ru位点分别充当催化ORR和OER位点，Ru SAs和MnO2之间的协同效应通过强电子相互作用有助于提高催化性能。组装锌空气电池时，在 318.5 mA cm−2 电流下可提供 230.0 mW cm−2 的最大功率密度。