Acta Chimica Sinica ›› 2014, Vol. 72 ›› Issue (8): 920-926.DOI: 10.6023/A14030233 Previous Articles     Next Articles

Special Issue: 纪念南开大学化学学科创建100周年



靳琪, 裴龙凯, 胡宇翔, 杜婧, 韩晓鹏, 程方益, 陈军   

  1. 先进能源材料化学教育部重点实验室 化学化工协同创新中心 南开大学化学学院 天津 300071
  • 投稿日期:2014-03-31 发布日期:2014-06-10
  • 通讯作者: 程方益
  • 基金资助:
    项目受国家自然科学基金优秀青年基金(No. 21322101)和重点项目(No. 21231005)、教育部“新世纪优秀人才支持计划”(No. ACET-13-0296)及111计划项目(No. B12015)资助

Solvo/Hydrothermal Preparation of MnOx@rGO Nanocomposites for Electrocatalytic Oxygen Reduction

Jin Qi, Pei Longkai, Hu Yuxiang, Du Jing, Han Xiaopeng, Cheng Fangyi, Chen Jun   

  1. Key Laboratory of Advanced Energy Materials Chemistry Ministry of Education, Collaborative Innovation Center of Chemical Science and Engineering, College of Chemistry, Nankai University, Tianjin 300071
  • Received:2014-03-31 Published:2014-06-10
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Nos. 21322101, 21231005), Ministry of Education (No. ACET-13-0296) and 111 Project (No. B12015).

Oxygen reduction reaction (ORR) catalysts in the cathode electrode are of crucial importance in determining the electrochemical performance of fuel cells and metal air batteries. In this work, the hybrid materials composed of MnOx nanoparticles on reduced graphene oxide (rGO) were selectively prepared via solvo/hydrothermal process and investigated as catalysts for the ORR in alkaline solution. The synthesis involved one-step in-situ reaction of MnSO4, KMnO4 and graphene oxide (GO) to form MnOx nucleus, and growth of nanosized Mn3O4 or MnOOH on the rGO matrix in ethanol or water. The X-ray diffraction (XRD), Raman, and FTIR spectroscopies indicated the reduction of GO and the formation of Mn3O4 and MnOOH phase. The scanning electron microscopy (SEM) and transmission electron microscopy (TEM) revealed that the Mn3O4 nanoparticles or MnOOH nanorods were homogenously dispersed over the few-layer rGO sheets. The MnOx content in the obtained MnOx@rGO composites was determined to be approximately 48% according to the TG analysis. The electrocatalytic properties of the prepared Mn3O4@rGO and MnOOH@rGO were evaluated by cyclic voltammetry (CV), linear sweep voltammetry (LSV) and rotating ring-disk electrode (RRDE) techniques, and were compared with neat Mn3O4 and MnOOH. Among the tested samples, MnOOH@rGO exhibited superior ORR activity with a onset-potential of -0.11 V, a half-wave potential of -0.32 V and a high kinetic limiting current density (Jk) of 4.69 mA·cm-2 at -0.6 V. Furthermore, MnOOH@rGO enabled an apparent 4-electron reduction of oxygen and showed considerable durability. The superior performance of MnOOH@rGO hydrid hybrid was attributed to the synergistic effect of rGO substrate and MnOOH nanorods and indicated its promising application as efficient ORR catalyst.

Key words: solvo-hydrothermal, manganese oxides, graphene, nanocomposite materials, oxygen reduction, electrocatalysts