Polysulfides adsorption and catalysis dual-sites on metal-doped molybdenum oxide nanoclusters for Li-S batteries with wide operating temperature  

作　　者：Jieshuangyang Chen Jie Lei Jinwei Zhou Xuanfeng Chen Rongyu Deng Mingzhi Qian Ya Chen Feixiang Wu 

机构地区：[1]School of Metallurgy and Environment, Engineering Research Center of the Ministry of Education for Advanced Battery Materials, Hunan Provincial Key Laboratory of Nonferrous Value-added Metallurgy, Central South University, Changsha, 410083, China [2]College of Materials Science and Engineering, Institute of New Energy Materials and Engineering, Fuzhou University, Fuzhou, 350108, China

出　　处：《Nano Research》2024年第11期9651-9661,共11页纳米研究（英文版）

基　　金：the National Natural Science Foundation of China(No.52172264);the Natural Science Foundation of Hunan Province of China(Nos.2021JJ10060 and 2022GK2033).

摘　　要：The development of electrocatalysts with high catalytic activity is conducive to enhancing polysulfides adsorption and reducing activation energy of polysulfides conversion, which can effectively reduce polysulfide shuttling in Li-S batteries. Herein, a novel catalyst NiCo-MoO_(x)/rGO (rGO = reduced graphene oxides) with ultra-nanometer scale and high dispersity is derived from the Anderson-type polyoxometalate precursors, which are electrostatically assembled on the multilayer rGO. The catalyst material possesses dual active sites, in which Ni-doped MoO_(x) exhibits strong polysulfide anchoring ability, while Co-doped MoO_(x) facilitates the polysulfides conversion reaction kinetics, thus breaking the Sabatier effect in the conventional electrocatalytic process. In addition, the prepared NiCo-MoO_(x)/rGO modified PP separator (NiCo-MoO_(x)/rGO@PP) can serve as a physical barrier to further inhibit the polysulfide shuttling effect and realize the rapid Li+ migration. The results demonstrate that Li-S coin cell with NiCo-MoO_(x)/rGO@PP separator shows excellent cycling performance with the discharge capacity of 680 mAh·g^(−1) after 600 cycles at 1 C and the capacity fading of 0.064% per cycle. The rate performance is also impressive with the remained capacity of 640 mAh·g^(−1) after 200 cycles even at 4 C. When the sulfur loading is 4.0 mg·cm^(−2) and electrolyte volume/sulfur mass ratio (E/S) ratio is 6.0 μL·mg^(−1), a specific capacity of 830 mAh·g^(−1) is achieved after 200 cycles with a capacity decay of 0.049% per cycle. More importantly, the cell with NiCo-MoO_(x)/rGO@PP separator exhibits cycling performance under wide operating temperature with the reversible capacities of 518, 715, and 915 mAh·g^(−1) after 100 cycles at −20, 0, and 60 °C, respectively. This study provides a new design approach of highly efficient catalysts for sulfur conversion reaction in Li-S batteries.

关 键 词：lithium-sulfur batteries doped molybdenum oxide separator modification adsorption and catalysis dual-sites wide temperature 

分 类 号：O64[理学—物理化学]