Synthesis and electrochemical performance of graphene-like WS_2

摘要

Graphene-like and platelike WS_2 were obtained by solid-state reactions. High-resolution (HR) TEM, BET, and Raman scattering studies show that the graphene-like WS_2 is a few-layer-structured material. It exhibits better electrochemical performances than the platelike WS_2. Structural characterization indicates that metallic W and Li_2S are the end products of discharge (0.01V versus Li~+/Li), whereas metallic W and S are the recharge (3.00V) products. In addition, X-ray absorption near-edge structure (XANES) characterization shows that the d electrons of W deviate towards the Li (or S) atom during the discharge/charge process, thus forming a weak bond between W and Li_2S (or S). Smashing the plate: Graphene-like WS_2 exhibits better electrochemical performance than platelike WS_2. XRD and X-ray absorption near-edge structure (XANES) analyses show that metallic W and Li_2S are the products of discharge, whereas metallic W and S are the products of recharge (see figure). The d electrons of W deviate towards the Li (or S) atom during the discharge/charge process to form a weak bond between W and Li_2S (or S).