Hierarchical Porous Carbon Spheres Loaded CoOX (CoOx/HPCS) for Efficient Oxygen Reduction Reaction in Alkaline Media

Abstract

AbstractThe development of efficient non‐noble metal catalysts for oxygen reduction reaction (ORR) in alkaline media is vital for wide application of numerous energy conversion devices. In this work, the CoOx/HPCS catalysts are demonstrated to show excellent activity toward ORR with more positive peak potential, initial potential, and half‐wave potential than pure HPCS. Moreover, the CoOx/HPCS exhibits a long‐term stability and a stronger methanol resistance compared to 20% Pt/C. The outstanding ORR activity for CoOx/HPCS is owing to its excellent characteristics, like: 1) a good conductivity of the carbon matrix to improve the electron transfer ability; 2) the rich hierarchical hollow carbon matrix and high surface area conducive to providing more accessible active sites and improving mass transportation; 3) the defect caused by oxygen vacancy beneficial for enhancing catalytic activity; 4) the synergistic effect between CoOx and HPCS support being crucial for ORR, thence enhancing the electrochemical performance of CoOx/HPCS.