Metal Oxide (Co3O4 and Mn3O4) Impregnation into S, N-doped Graphene for Oxygen Reduction Reaction (ORR)

Materials

Penny Mathumba¹  EmmanuelI. Iwuoha¹  Cristina Freire²  DianaM. Fernandes²  Renata Matos² 

[1] Department of Chemistry, Faculty of Science, University of the Western Cape (UWC), Cape Town, Bellville 7535, South Africa;REQUIMTE/LAQV, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto, 4160-007 Porto, Portugal;

关键词: oxygen reduction;    carbon material;    metal oxides;    heteroatom doping;   

DOI  :  10.3390/ma13071562

来源: DOAJ

【 摘 要 】

To address aggravating environmental and energy problems, active, efficient, low-cost, and robust electrocatalysts (ECs) are actively pursued as substitutes for the current noble metal ECs. Therefore, in this study, we report the preparation of graphene flakes (GF) doped with S and N using 2-5-dimercapto-1,3,4-thiadiazole (S₃N₂) as precursor followed by the immobilization of cobalt spinel oxide (Co₃O₄) or manganese spinel oxide (Mn₃O₄) nanoparticles through a one-step co-precipitation procedure (Co/S₃N₂–GF and Mn/S₃N₂–GF). Characterization by different physicochemical techniques (Fourier Transform Infrared (FTIR), Raman spectroscopy, Transmission Electron Microscopy (TEM) and X-ray Diffraction (XRD)) of both composites shows the preservation of the metal oxide spinel structure and further confirms the successful preparation of the envisaged electrocatalysts. Co/S₃N₂–GF composite exhibits the best ORR performance with an onset potential of 0.91 V vs. RHE, a diffusion-limiting current density of −4.50 mA cm⁻² and selectivity for the direct four-electron pathway, matching the results obtained for commercial Pt/C. Moreover, both Co/S₃N₂–GF and Mn/S₃N₂–GF showed excellent tolerance to methanol poisoning and good stability.

【 授权许可】

Unknown