Zhang Xu, Yu Peng, Xing Gengyu, Xie Ying, Zhang Xinxin, Zhang Guangying, Sun Fanfei, Wang Lei
Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education of the People's Republic of China, Heilongjiang University, Harbin, 150080, China.
Key Laboratory for Photonic and Electronic Bandgap Materials, Ministry of Education, School of Physics and Electronic Engineering, Harbin Normal University, Harbin, 150025, China.
Small. 2022 Dec;18(51):e2205228. doi: 10.1002/smll.202205228. Epub 2022 Nov 3.
The development of nonprecious metal catalysts with both oxygen reduction and evolution reactions (ORR/OER) is very important for Zn-air batteries (ZABs). Herein, a Co N particles and Fe single atoms co-doped hollow carbon nanofiber self-supporting membrane (H-CoFe@NCNF) is synthesized by a coaxial electrospinning strategy combined with pyrolysis. X-ray absorption fine spectroscopy analyses confirm the state of the cobalt nitride and Fe single atoms. As a result, H-CoFe@NCNF exhibits a superior bifunctional performance of E = 0.96 V for ORR, and E = 1.68 V for OER. Density functional theory calculations show that H-CoFe@NCNF has a moderate binding strength to oxygen due to the coexistence of nanoparticle and single atoms. Meanwhile, the Co site is more favorable to the OER, while the Fe site facilitates the ORR, and the proton and charge transfer between N and metal atoms further lower the reaction barriers. The liquid ZAB composed of H-CoFe@NCNF has a charge-discharge performance of ≈1100 h and a peak power density of 205 mW cm . The quasi-solid-state ZAB assembled by the self-supporting membrane of H-CoFe@NCNF is proven to operate stably in any bending condition.
开发具有氧还原和析氧反应（ORR/OER）的非贵金属催化剂对锌空气电池（ZAB）非常重要。在此，通过同轴静电纺丝策略结合热解合成了一种钴氮颗粒和铁单原子共掺杂的中空碳纳米纤维自支撑膜（H-CoFe@NCNF）。X射线吸收精细光谱分析证实了氮化钴和铁单原子的状态。结果，H-CoFe@NCNF表现出优异的双功能性能，ORR的E = 0.96 V，OER的E = 1.68 V。密度泛函理论计算表明，由于纳米颗粒和单原子的共存，H-CoFe@NCNF对氧具有适中的结合强度。同时，Co位点更有利于OER，而Fe位点促进ORR，N与金属原子之间的质子和电荷转移进一步降低了反应势垒。由H-CoFe@NCNF组成的液体ZAB具有约1100 h的充放电性能和205 mW cm的峰值功率密度。由H-CoFe@NCNF自支撑膜组装的准固态ZAB被证明在任何弯曲条件下都能稳定运行。
