Zhao Yongzhi, Zhang Zili, Liu Luan, Wang Yong, Wu Tong, Qin Wanjun, Liu Sijia, Jia Baorui, Wu Haoyang, Zhang Deyin, Qu Xuanhui, Qi Genggeng, Giannelis Emmanuel P, Qin Mingli, Guo Shaojun
Institute for Advanced Materials and Technology, University of Science and Technology Beijing, Beijing 100083, China.
Department of Electrical Engineering, Zhengzhou University, Zhengzhou 450001, China.
J Am Chem Soc. 2022 Nov 16;144(45):20571-20581. doi: 10.1021/jacs.2c05247. Epub 2022 Nov 4.
The highly efficient bifunctional catalyst for the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER) is the key to achieving high-performance rechargeable Zn-air batteries. Non-precious-metal single-atom catalysts (SACs) have attracted intense interest due to their low cost and very high metal atomic utilization; however, high-activity bifunctional non-precious-metal SACs are still rare. Herein, we develop a new nanospace-confined sulfur-enamine copolymerization strategy to prepare a new type of bifunctional Mo SACs with O/S co-coordination (Mo-OS-C) supported on the multilayered, hierarchically porous hollow tubes. The as-prepared catalyst can not only expose more active sites and facilitate mass transfer due to their combined micropores, mesopores, and macropores but also have the S/O co-coordination structure for optimizing the adsorption energies of the ORR intermediates. Its ORR activity is among the highest, and it shows a low overpotential of 324 mV for the OER at 10 mA cm in all of the reported Mo-based catalysts. When assembled in a Zn-air battery, it exhibits a high maximal power density of 197.3 mW cm and a long service life of 50 hours, superior to those of Zn-air batteries using commercial Pt/C+IrO.
用于氧还原反应（ORR）和析氧反应（OER）的高效双功能催化剂是实现高性能可充电锌空气电池的关键。非贵金属单原子催化剂（SACs）因其低成本和极高的金属原子利用率而备受关注；然而，高活性双功能非贵金属SACs仍然很少见。在此，我们开发了一种新的纳米空间限制硫-烯胺共聚策略，以制备一种新型的双功能Mo SACs，其具有O/S共配位（Mo-OS-C），负载在多层分级多孔中空管上。所制备的催化剂不仅由于其组合的微孔、中孔和大孔而能暴露更多活性位点并促进传质，而且具有S/O共配位结构以优化ORR中间体的吸附能。其ORR活性是最高的之一，并且在所有报道的Mo基催化剂中，在10 mA cm下OER的过电位低至324 mV。当组装在锌空气电池中时，它表现出197.3 mW cm的高最大功率密度和50小时的长使用寿命，优于使用商业Pt/C+IrO的锌空气电池。
