Chen Yuqing, Qiao Shanshan, Tang Yanhong, Du Yi, Zhang Danyu, Wang Wenjie, Zhang Hao, Sun Xuhui, Liu Chengbin
State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha, Hunan 410082, People's Republic of China.
College of Materials Science and Engineering, Hunan University, Changsha, Hunan 410082, People's Republic of China.
ACS Nano. 2022 Sep 27;16(9):15273-15285. doi: 10.1021/acsnano.2c06700. Epub 2022 Sep 8.
Flexible solid-state zinc-air batteries (ZABs) with low cost, excellent safety, and high energy density has been considered as one of ideal power sources for portable and wearable electronic devices, while their practical applications are still hindered by the kinetically sluggish cathodic oxygen reduction and oxygen evolution reactions (ORR/OER). Herein, a Janus-structured flexible free-standing bifunctional oxygen electrocatalyst, with OER-active O, N co-coordinated Ni single atoms and ORR-active CoO@CoS nanosheet arrays being separately integrated at the inner and outer walls of flexible hollow carbon nanofibers (Ni-SAs/HCNFs/Co-NAs), is reported. Benefiting from the sophisticated topological structure and atomic-level-designed chemical compositions, Ni-SAs/HCNFs/Co-NAs exhibits outstanding bifunctional catalytic activity with the Δ index of 0.65 V, representing the current state-of-the-art flexible free-standing bifunctional ORR/OER electrocatalyst. Impressively, the Ni-SAs/HCNFs/Co-NAs-based liquid ZAB show a high open-circuit potential (1.45 V), high capacity (808 mAh g Zn), and extremely long life (over 200 h at 10 mA cm), and the assembled flexible all-solid-state ZABs have excellent cycle stability (over 80 h). This work provides an efficient strategy for developing high-performance bifunctional ORR/OER electrocatalysts for commercial applications.
具有低成本、卓越安全性和高能量密度的柔性固态锌空气电池（ZABs），被认为是便携式和可穿戴电子设备的理想电源之一，但其实际应用仍受到动力学迟缓的阴极氧还原和析氧反应（ORR/OER）的阻碍。在此，报道了一种Janus结构的柔性自支撑双功能氧电催化剂，其中具有OER活性的O、N共配位Ni单原子和ORR活性的CoO@CoS纳米片阵列分别集成在柔性中空碳纳米纤维（Ni-SAs/HCNFs/Co-NAs）的内壁和外壁。得益于其精细的拓扑结构和原子级设计的化学成分，Ni-SAs/HCNFs/Co-NAs表现出出色的双功能催化活性，Δ指数为0.65 V，代表了当前最先进的柔性自支撑双功能ORR/OER电催化剂。令人印象深刻的是，基于Ni-SAs/HCNFs/Co-NAs的液体ZAB显示出高开路电位（1.45 V）、高容量（808 mAh g Zn）和极长的寿命（在10 mA cm下超过200小时），并且组装的柔性全固态ZAB具有出色的循环稳定性（超过80小时）。这项工作为开发用于商业应用的高性能双功能ORR/OER电催化剂提供了一种有效策略。
