Dual-Phase Spinel MnCo2O4and Spinel MnCo2O4/Nanocarbon Hybrids for Electrocatalytic Oxygen Reduction and Evolution

• DOI: 10.1021/am502675c
• Publication Date: 2014-07-24T14:54:19Z
• Authors: Xiaoming Ge; Yayuan Liu; F. W. Thomas Goh; T. S. Andy Hor; Yun Zong; Peng Xiao; Zheng Zhang; Suo Hon Lim; Bing Li; Xin Wang; Zhaolin Liu
• Keywords: oxygen reduction reaction; Transition-metal oxide; spinel; Oxygen evolution reaction; nanocarbon; metal-air battery; Spinel; 600; 02 engineering and technology; 540; Covalent coupling; 7. Clean energy; Oxygen reduction reaction; covalent coupling; Nanocarbon; oxygen evolution reaction; transition-metal oxide; Metal-air battery; 0210 nano-technology

Oxygen reduction reaction (ORR) and oxygen evolution (OER) are essential reactions for energy-storage -conversion devices relying on electrochemistry. High-performance, nonprecious metal-based hybrid catalysts developed from postsynthesis integration of dual-phase spinel MnCo2O4 (dp-MnCo2O4) nanocrystals with nanocarbon materials, e.g., carbon nanotube (CNT) nitrogen-doped reduced graphene oxide (N-rGO). The synergic covalent coupling between dp-MnCo2O4 nanocarbons effectively enhances both the bifunctional ORR OER activities spinel/nanocarbon catalysts. dp-MnCo2O4/N-rGO exhibited comparable activity superior compared to commercial 30 wt % platinum supported black (Pt/C). An electrically rechargeable zinc-air battery using dp-MnCo2O4/CNT cathode was successfully operated 64 discharge-charge cycles (or 768 h equivalent), significantly outperforming Pt/C counterpart, which could only survive up 108 under similar conditions.