山东大学熊胜林团队报道了N掺杂MXene纳米片上一步生长超薄CoSe₂纳米带，用于枝晶抑制和动力学加速锂硫化学。相关研究成果发表在2024年3月21日出版的《科学通报》。

多硫化物锂（LiPSs）的穿梭效应、S阴极上缓慢的多硫化物氧化还原动力学，以及锂金属阳极上不可控的枝晶生长抑制了锂硫（Li–S）电池的实际应用。因此，在对锂离子电池进行改性时，必须同时考虑阴极侧和阳极侧。

该文中，研究人员首次采用一步溶剂热法在2D N掺杂的MXene纳米片上，原位生长二维（2D）超薄CoSe₂纳米带(CoSe₂@N-MXene)。由于其独特的2D/2D结构，CoSe₂@N-MXene可以通过冷冻干燥加工成皱折的纳米片，通过真空过滤加工成柔性和独立的薄膜。

这些皱巴巴的具有丰富活性位点和内部空间的CoSe₂@N-MXene纳米片，由于具有较强的吸附能力和对LiPSs的催化转化作用，可以作为S主体加速多硫化物氧化还原动力学，抑制LiPSs穿梭效应。同时CoSe₂@N-MXene薄膜(CoSe₂@NMF)由于含有亲锂的CoSe₂和N位点，所以可以作为电流收集器来促进均匀的Li沉积。在CoSe₂@N-MXene对S阴极和Li金属阳极的系统作用下，提高了Li–S电池的电化学性能和安全性能。CoSe₂@NMF在柔性储能装置中也显示出优异的存储性能。

附：英文原文

Title: One-step growth of ultrathin CoSe2 nanobelts on N-doped MXene nanosheets for dendrite-inhibited and kinetic-accelerated lithium–sulfur chemistry

Author: Chuanliang Wei , Zhengran Wang , Peng Wang , Xinlu Zhang , Xuguang An , Jinkui Feng , Baojuan Xi , Shenglin Xiong

Issue&Volume: 2024/03/21

Abstract: The practical application of lithium–sulfur (Li–S) batteries is inhibited by the shuttle effect of lithium polysulfides (LiPSs) and slow polysulfide redox kinetics on the S cathode as well as the uncontrollable growth of dendrites on the Li metal anode. Therefore, both cathode and anode sides must be considered when modifying LiS batteries. Herein, two-dimensional (2D) ultrathin CoSe2 nanobelts are in situ grown on 2D N-doped MXene nanosheets (CoSe2@N-MXene) via one-step solvothermal process for the first time. Owing to its unique 2D/2D structure, CoSe2@N-MXene can be processed to crumpled nanosheets by freeze-drying and flexible and freestanding films by vacuum filtration. These crumpled CoSe2@N-MXene nanosheets with abundant active sites and inner spaces can act as S hosts to accelerate polysulfide redox kinetics and suppress the shuttle effect of LiPSs owing to their strong adsorption ability and catalytic conversion effect with LiPSs. Meanwhile, the CoSe2@N-MXene film (CoSe2@NMF) can act as a current collector to promote uniform Li deposition because it contains lithiophilic CoSe2 and N sites. Under the systematic effect of CoSe2@N-MXene on S cathode and Li metal anode, the electrochemical and safety performance of Li–S batteries are improved. CoSe2@NMF also shows excellent storage performances in flexible energy storage devices.

DOI: 10.1016/j.scib.2024.03.043

Source: https://www.sciencedirect.com/science/article/abs/pii/S2095927324001993