Rapid Microwave Synthesis of β-SnWO4 Nanoparticles: An Efficient Anode Material for Lithium Ion Batteries

We report a facile synthesis of β-SnWO4 nanoparticles via a microwave heat treatment using SnCl2 and H2WO4 in the presence of tamarind seed powder. An X-ray diffraction analysis confirmed a crystalline nature revealing a cubic structure of β-SnWO4 nanoparticles. The morphological features were visualized using a scanning electron microscope that exhibited homogenously distributed clusters of nanoparticles, which were further confirmed using a transmission electron microscope. The micrographs also displayed some porosity. Energy dispersive X-ray spectroscopy confirmed the elemental contents such as tin, oxygen and tungsten in the same stoichiometric ratio as expected by the respective empirical formula. A high-resolution transmission electron microscope was used to find the d-spacing, which was ultimately used to analyze the structural parameters. The spectrum obtained using Fourier transform infrared spectroscopy illuminated different stretching vibrations. Additionally, a Barrett–Joyner–Halenda analysis was carried out to investigate the N2 adsorption-desorption isotherm as well as to govern the pore size distribution. Cyclic voltammetry measurements were implemented to analyze the ongoing electrode reactions throughout the charge/discharge for the β-SnWO4 nanostructures. The galvanometric charge/discharge curves for β-SnWO4 are also discussed. A high specific capacitance (600 mAhg–1 at 0.1 C) and excellent columbic efficiency (~100%) were achieved.