Nickel-doped monoclinic WO3 as high performance anode material for rechargeable lithium ion battery

The anode materials are one of the critical components in rechargeable lithium ion batteries (LIBs). The monoclinic tungsten trioxide (mWO3) is introduced as interesting anode electrode for LIBs due to its good structure for intercalation and de-intercalation of lithium ions, high abundance and various oxidation state of tungsten and etc. In this study, we prepare and investigate the effect of various amounts of nickel dopant on characteristics and electrochemical properties of the mWO3 as the anode electrode in a rechargeable LIB. The experimental investigations confirm that the number of nickel atoms has a remarkable effect on controlling spherical particle diameter, crystallite size, and electrochemical properties of mWO3. The electrochemical results demonstrate that the 10 wt% nickel dopant leads to make the highest improvements for electrochemical behaviors of mWO3. The sample exhibits higher 1st/2nd electrochemical capacities (1287/1012 mAh g−1 at 100 mA g−1), good cycle life (capacity retention of 79.60% after 500 cycles at 100 mA g−1), and better rate capability (650.2 mAh g−1 even at 1000 mA g−1) among un-doped and doped mWO3 samples, including 5 and 20 wt% nickel atoms. These improvements can be related to the spherical morphology of nanoparticles and high electrical conductivity making by nickel dopant, which is beneficial to enhance lithium-ion diffusion and electron transfer in the monoclinic structure of WO3. The anode electrode reported here exhibits excellent properties in LIBs for various energy storage applications..