Fabrication of Non-precious Vanadium Tungsten Nanocomposite for Enhanced Electrocatalytic Oxygen Reduction Reaction

Abstract

For the commercialization of alkaline fuel cells and metal air batteries, the advances in non-precious, cheap, stable electrocatalysts for the oxygen reduction reaction (ORR) and highly active remain a major problem. To overcome this problem, a facile approach was established to fabricate non-precious metal electrocatalysts, such as nanoparticles, pristine V2O5 and their WO3 hybrids. This is the first study reporting the utilization of monoclinic-WO3-nanocrystal-coupled V2O5 that serves as ORR catalysts. Compared with 50 wt.% WO3 with 50 wt.% V2O5 (VW-2) spheres and pristine V2O5, the hybrid catalyst of 25 wt.% WO3 and 75 wt.% V2O5 (VW-1) spheres exhibits outstanding catalytic activity towards ORR. In addition, the hybrid of 25 wt.% WO3 and 75 wt.% V2O5 (VW-1) exhibits a higher long-term durability and catalytic activity than high-quality commercial Pt/C catalysts, which renders the composites of WO3/V2O5 composites hybrid a high-capacity candidate for non-precious, high-performance, metal-based electrocatalysts having high efficiency and low cost for electrochemical energy conversion. The enhanced activity of WO3/V2O5 composites is mainly obtained from the improved structural openness in the V2O5 tunnel structure when coupled with WO3.