Electrochimica Acta, Vol.153, 49-54, 2015
Chemical Vapor Synthesized WS2-Embedded Polystyrene-derived Porous Carbon as Superior Long-term Cycling Life Anode Material for Li-ion Batteries
By immersion of macroporous polystyrene beads covalently bound with negatively charged sulfonate groups in tungstic acid and subsequent carbonization in presence of sulfur vapor, the polystyrene-derived porous carbon (PDPC) with uniformly embedded WS2 nanoparticles of similar to 20 wt% (denoted as PDPC/WS2) was fabricated as an anode material for Li-ion batteries. Compared to the pure PDPC, the uniform chemical vapor synthesized embedment of WS2 nanoparticles lead to the highly improved electrochemical performance. At the high current rate of 1 A/g, it delivers the continuous increase in capacity with cycling and similar to 100% Coulumbic efficiency over more than 1000 cycles, and reversible capacity of 282 mAh/g is retained after the 1220 cycles. By tuning again up to 2 A/g, the PDPC/WS2 anode can maintain the impressive capacity retentions of 81% and 70% after 1000 and 2000 more cycles, respectively. The cycling test of the PDPC/WS2 anode at the high rate of 4 A/g demonstrate the cycling stability over more than 7000 cycles. (C) 2014 Elsevier Ltd. All rights reserved.