Microwave‐assisted synthesis of cobalt‐polyoxometalate@carbon black nanocomposites and their electrocatalytic ability toward oxygen reduction reaction

Summary Improving the stability and efficiency of non‐noble metal based ORR (oxygen reduction reaction) electrocatalyst is crucial for the commercialization of fuel cell technology. Here, we report the synthesis of cobalt‐polyoxometalate nanocomposite with carbon (CoP@C) by greener strategy, which shows an interesting enhancement in the kinetics of oxygen electroreduction process. The CoP@C nanocomposite exhibited improved catalytic activity toward ORR with Eonset 1.00 V vs RHE and current density of 4.2 mA/cm2 at 1600 rpm in alkaline condition. Further, CoP@C electrocatalyst showed a single step ~4 electron transfer pathway, high tolerance to methanol, and exhibited superior stability compared with 20 wt% Pt/C. Thus, CoP@C could be a cheaper and potential candidate for ORR electrocatalysis in fuel cells. The superiority of the catalyst in terms of activity and durability arises due to the uniform distribution of cobalt‐polyoxometalate nanoclusters on carbon surface and the synergetic effect of POM, cobalt, and carbon. A simple and rapid microwave‐assisted approach was utilized for the formation of cobalt and tungsten oxide nanoparticles adsorbed on the surface of carbon; which favor adsorption of oxygen and its effective electro‐reduction.