Shen Yanbin, Deng Shengjue, Liu Ping, Zhang Yan, Li Yahao, Tong Xili, Shen Hong, Liu Qi, Pan Guoxiang, Zhang Lingjie, Wang Xiuli, Xia Xinhui, Tu Jiangping
State Key Laboratory of Silicon Materials, Key Laboratory of Advanced Materials and Applications for Batteries of Zhejiang Province, and Department of Materials Science and Engineering, Zhejiang University, Hangzhou, 310027, P. R. China.
State Key Laboratory of Coal Conversation, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan, 030001, P. R. China.
Small. 2020 Oct;16(40):e2004072. doi: 10.1002/smll.202004072. Epub 2020 Sep 6.
Tin disulfide (SnS ) shows promising properties toward sodium ion storage with high capacity, but its cycle life and high rate capability are still undermined as a result of poor reaction kinetics and unstable structure. In this work, phosphate ion (PO )-doped SnS (P-SnS ) nanoflake arrays on conductive TiC/C backbone are reported to form high-quality P-SnS @TiC/C arrays via a hydrothermal-chemical vapor deposition method. By virtue of the synergistic effect between PO doping and conductive network of TiC/C arrays, enhanced electronic conductivity and enlarged interlayer spacing are realized in the designed P-SnS @TiC/C arrays. Moreover, the introduced PO can result in favorable intercalation/deintercalation of Na and accelerate electrochemical reaction kinetics. Notably, lower bandgap and enhanced electronic conductivity owing to the introduction of PO are demonstrated by density function theory calculations and UV-visible absorption spectra. In view of these positive factors above, the P-SnS @TiC/C electrode delivers a high capacity of 1293.5 mAh g at 0.1 A g and exhibits good rate capability (476.7 mAh g at 5 A g ), much better than the SnS @TiC/C counterpart. This work may trigger new enthusiasm on construction of advanced metal sulfide electrodes for application in rechargeable alkali ion batteries.
二硫化锡（SnS₂）在钠离子存储方面展现出具有高容量的良好性能，但其循环寿命和高倍率性能仍因反应动力学差和结构不稳定而受到影响。在这项工作中，据报道，通过水热 - 化学气相沉积法在导电TiC/C骨架上制备了磷酸根离子（PO₄³⁻）掺杂的SnS₂（P - SnS₂）纳米片阵列，形成了高质量的P - SnS₂@TiC/C阵列。借助PO₄³⁻掺杂与TiC/C阵列导电网络之间的协同效应，在设计的P - SnS₂@TiC/C阵列中实现了电子电导率的提高和层间距的增大。此外，引入的PO₄³⁻可促进Na⁺的有利嵌入/脱出，并加速电化学反应动力学。值得注意的是，密度泛函理论计算和紫外 - 可见吸收光谱表明，由于PO₄³⁻的引入，带隙降低且电子电导率增强。鉴于上述这些积极因素，P - SnS₂@TiC/C电极在0.1 A g⁻¹时具有1293.5 mAh g⁻¹的高容量，并表现出良好的倍率性能（在5 A g⁻¹时为476.7 mAh g⁻¹），远优于SnS₂@TiC/C电极。这项工作可能会引发人们对构建用于可充电碱离子电池的先进金属硫化物电极的新热情。
