NiMoO<sub>4</sub> Nanosheets Anchored on NS Doped Carbon Clothes with Hierarchical Structure as a Bidirectional Catalyst toward Accelerating Polysulfides Conversion for LiS Battery
Tingting Sun, Xiaomei Zhao, Bo Li, Hongbo Shu, Lipan Luo, Wenlong Xia, Manfang Chen, Peng Zeng, Xiukang Yang, Ping Gao, Yong Pei, Xianyou Wang
Abstract
Abstract The serious shuttle effect, sluggish reduction kinetics of polysulfides and the difficult oxidation reaction of Li 2 S have hindered LiS battery practical application. Herein, a 3D hierarchical structure composed of NiMoO 4 nanosheets in situ anchored on NS doped carbon clothes (NiMoO 4 @NSCC) as the free‐standing host is creatively designed and constructed for LiS battery. Dual transitional metal oxide (NiMoO 4 ) increases the electrons density near the Fermi level due to the contribution of the incorporating molybdenum (Mo), leading to the smaller bandgap, and thus stronger metallic properties compared with NiO. Furthermore, as a bidirectional catalyst, NiMoO 4 is proposed to facilitate reductions of polysulfides through lengthening the SS bond distance of Li 2 S 4 and reducing the free energy of polysulfides conversion, meanwhile promote critical oxidation of insulative discharge product (Li 2 S) via lengthening LiS bond distance of Li 2 S and decreasing Li 2 S decomposition barrier. Therefore, after loading sulfur (2 mg cm −2 ), NiMoO 4 @NSCC/S as the self‐supporting cathode for the LiS battery exhibits impressive long cycle stability. This study proposes a concept of a bidirectional catalyst with dual metal oxides, which would supply a novel vision to construct the high‐performance LiS battery.