Zheng Yang, Khan Mustafa, Yan Suxia, Yang Dahai, Chen Ying, Zhang Li, Song Xiaohui, Li Guochun, Liu Junfeng, Wang Yong
Institute for Energy Research, Jiangsu University, Zhenjiang, China.
School of Materials Science and Engineering, Hefei University of Technology, Hefei, China.
Front Chem. 2024 May 16;12:1416059. doi: 10.3389/fchem.2024.1416059. eCollection 2024.
The cathode in lithium-selenium (Li-Se) batteries has garnered extensive attention owing to its superior specific capacity and enhanced conductivity compared to sulfur. Nonetheless, the adoption and advancement of Li-Se batteries face significant challenges due to selenium's low reactivity, substantial volume fluctuations, and the shuttle effect associated with polyselenides. Single-atom catalysts (SACs) are under the spotlight for their outstanding catalytic efficiency and optimal atomic utilization. To address the challenges of selenium's low chemical activity and volume expansion in Li-Se batteries, through electrospun, we have developed a lotus root-inspired carbon nanofiber (CNF) material, featured internal multi-channels and anchored with molybdenum (Mo) single atoms (Mo@CNFs). Mo single atoms significantly enhance the conversion kinetics of selenium (Se), facilitating rapid formation of LiSe. The internally structured multi-channel CNF serves as an effective host matrix for Se, mitigating its volume expansion during the electrochemical process. The resulting cathode, Se/Mo@CNF composite, exhibits a high discharge specific capacity, superior rate performance, and impressive cycle stability in Li-Se batteries. After 500 cycles at a current density of 1 C, it maintains a capacity retention rate of 82% and nearly 100% coulombic efficiency (CE). This research offers a new avenue for the application of single-atom materials in enhancing advanced Li-Se battery performance.
锂硒（Li-Se）电池的阴极因其比硫具有更高的比容量和增强的导电性而备受关注。然而，由于硒的低反应活性、大量的体积波动以及与多硒化物相关的穿梭效应，Li-Se电池的应用和发展面临重大挑战。单原子催化剂（SACs）因其出色的催化效率和最佳的原子利用率而备受关注。为了解决Li-Se电池中硒的低化学活性和体积膨胀的挑战，我们通过静电纺丝开发了一种受莲藕启发的碳纳米纤维（CNF）材料，其具有内部多通道并锚定有钼（Mo）单原子（Mo@CNFs）。Mo单原子显著提高了硒（Se）的转化动力学，促进了LiSe的快速形成。内部结构化的多通道CNF作为Se的有效主体基质，减轻了其在电化学过程中的体积膨胀。所得的阴极，即Se/Mo@CNF复合材料，在Li-Se电池中表现出高放电比容量、优异的倍率性能和令人印象深刻的循环稳定性。在1 C的电流密度下循环500次后，它保持82%的容量保持率和近100%的库仑效率（CE）。这项研究为单原子材料在提升先进Li-Se电池性能方面的应用提供了一条新途径。
