Chemical Vapor Synthesized WS2-Embedded Polystyrene-derived Porous Carbon as Superior Long-term Cycling Life Anode Material for Li-ion Batteries

• Polystyrene-derived porous carbon with uniformly embedded WS2 nanoparticles has been prepared by a chemical vapor method.
• At the current rate of 1 A/g, the reversible capacity of 282 mAh/g is retained after the 1220 cycles for PDPC/WS2.
• The cycling test of the PDPC/WS2 anode at the high rate of 4 A/g demonstrate a cycling stability over 7000 cycles.

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 ∼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 ∼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.