采用脉冲激光溅射Sn和Se粉末的混合靶制备SnSe薄膜,XRD结果显示室温下得到的是Sn和Se的混合薄膜,当基片温度为200℃时,薄膜主要由晶态的SnSe组成.该薄膜的首次放电容量为498 mAh·g^-1,30次循环之后的放电容量为260 mAh·g^-1.充放电测试、循环伏安曲线和ex-situ XRD结果显示,SnSe能够和Li发生可逆的电化学反应,充电过程中能够重新生成SnSe,表现出不同于其它氧族元素锡化物的电化学性质.
SnSe thin film has been successfully fabricated by using pulsed laser ablation of mixed target of Sn and Se. The structure and electrochemical properties of the as-deposited thin film at different substrate temperatures have been investigated by X-ray diffraction (XRD), the charge/discharge and cyclic voltammetry (CV) measurements. The thin film deposited at room temperature consisted of a mixture of Sn and Se. When the substrate temperature was 200℃, the as-deposited thin film was mainly composed of crystallized SnSe. The reversible discharge capacities fell into the range from 260 mAh·g^-1 to 498 mAh·g^-1. A reduction and an oxidation peaks at 0.75 V and 2.17 V from CV curves of Li/SnSe cell were firstly found, indicating the reversible formation and decomposition of Li2Se. This feature is utterly different from those of SnOx and SnSx, in which Li2O and Li2S are inactive. The lithium electrochemical reaction of SnSe thin film electrode was investigated by XRD. Both classical alloying process and the selenylation-reduction of metal tin were revealed in lithium electrochemical reaction of SnSe. SnSe as the starting material for conversion to the Li-Sn alloy can improve its electrochemical performance with high reversible capacity and good stable cycle, demonstrating to be one of promise anode materials for future rechargeable lithium batteries.