Ordered Mesoporous Crystalline Mo-Doped WO2 Materials with High Tap Density as Anode Material for Lithium Ion Batteries

Abstract

Highly ordered mesoporous crystalline Mo-doped WO2 (MoxW1-xO2: 1 > x > 0.08) materials with different molybdenum contents were synthesized via a nanocasting strategy using mesoporous silica KIT-6 as a hard template. The presence of molybdenum significantly increased the rate of reduction of tungsten trioxide to tungsten dioxide using hydrogen gas as the reducing agent, and it also prevented the dioxide product from being further reduced to zerovalent metal tungsten. This molybdenum doping strategy provides a new solution for the synthesis of WO2-based materials with well-defined nanostructures. The obtained mesoporous Mo0.14W0.86O2 material possessed a metallic conductivity (0.8 Ω cm, 300 K) and a high tap density of 3.6 g cm-3. This material exhibits a high and reversible lithium storage capacity of 635 mAh g-1 and is stable up to at least 70 cycles without noticeable fading.