通过协同吸附/电催化效应制备的独特柔性NiFeO@S/rGO-CNT电极用于高性能锂硫电池

Unique Flexible NiFeO@S/rGO-CNT Electrode via the Synergistic Adsorption/Electrocatalysis Effect toward High-Performance Lithium-Sulfur Batteries.

作者信息

Wang Hongqiang, Zhang Na, Li Ying, Zhang Pengyao, Chen Zhuo, Zhang Chunfang, Qiao Xue, Dai Yejing, Wang Qinghong, Liu Shuanghe

机构信息

Key Laboratory of Analytical Science and Technology of Hebei Province, College of Chemistry & Environmental Science , Hebei University , Baoding 071002 , PR China.

Fengfan Company Limited , Baoding , Hebei 071057 , PR China.

出版信息

J Phys Chem Lett. 2019 Nov 7;10(21):6518-6524. doi: 10.1021/acs.jpclett.9b02649. Epub 2019 Oct 15.

DOI:10.1021/acs.jpclett.9b02649

PMID:31596089

Abstract

A unique flexible NiFeO hollow sphere@S/rGO-CNT (NiFeO@S/C) cathode was rationally designed and synthesized to tackle the issues of lithium-sulfur batteries. In this strategy, the introduced rGO and CNTs offer a flexible and conductive skeleton to facilitate the transport of electrons and/or ions and a physical barrier to confine polysulfides. Furthermore, as an efficient sulfur host, NiFeO hollow spheres can further absorb the soluble polysulfides by strong chemical interaction due to their intrinsic polarity and also serve as a catalyst to promote the redox kinetics of polysulfide conversion. Benefiting from the synergism of the physical confinement, polar chemical adsorption, and catalytic conversion, the as-prepared flexible NiFeO@S/C electrode delivers a high initial capacity of 1193 mAh g at 100 mA g and excellent long-term cycling stability up to 500 cycles with a low decay rate of 0.059% per cycle at 500 mA g.

摘要

为解决锂硫电池的问题，合理设计并合成了一种独特的柔性NiFeO空心球@S/rGO-CNT（NiFeO@S/C）阴极。在该策略中，引入的rGO和CNTs提供了一个柔性导电骨架，以促进电子和/或离子的传输，并形成物理屏障来限制多硫化物。此外，作为一种高效的硫宿主，NiFeO空心球由于其固有的极性，可以通过强化学相互作用进一步吸收可溶性多硫化物，并且还作为催化剂促进多硫化物转化的氧化还原动力学。得益于物理限制、极性化学吸附和催化转化的协同作用，所制备的柔性NiFeO@S/C电极在100 mA g下具有1193 mAh g的高初始容量，在500 mA g下经过500次循环具有优异的长期循环稳定性，每循环的低衰减率为0.059%。