Conductive nitride-modified tungsten oxide catalyst improves electrochemical performance of lithium-sulfur batteries

Abstract:

In this study, WO2.9-W2N can be obtained by spraying the precursor during the preparation of carbon nanotube films (CNTs), followed by hydrothermal treatment and calcination. The use of W2N can improve the poor conductivity of WO3. In addition, the oxygen vacancies can be caused by WO2.9 that provide more active sites for the deposition of Li2S, and form Li-O with polysulfides (LiPSs), Li-N bond. The results demonstrate the chemical adsorption and anchoringof LiPSs onto the matrix strengthened, and thereby the prepared battery indicates excellent electrochemical performances, after 500 cycles at a rate of 0.2 C, the discharge specific capacity remains 850 mAh g-1, showing excellent electrochemical reaction kinetics and its catalytic effect to the electrochemical reactions. Therefore, the shuttling inhibition of WO2.9-W2N/CNTs is mainly occurred by trapping-anchoring-catalytic conversion.