Search

Cathode electrocatalyst is quite critical to realize the application of microbial fuel cells (MFCs). Perovskite oxides have been considered as potential MFCs cathode catalysts to replace Pt/C. Herein, Cu-doped perovskite oxide with a stable porous structure and excellent conductivity was successfully prepared through a sol-gel method. Due to the incorporation of Cu, CaFe 0.9 Cu 0.1 O 3 has more micropores and a larger surface area, which are more conducive to contact with oxygen. Doping Cu resulted in more Fe3+ in B-site and thus enhanced its binding capability to oxygen molecules. The data from electrochemical test demonstrated that the as-prepared catalyst has good conductivity, high stability, and excellent ORR properties. Compared with Pt/C catalyst, CaFe 0.9 Cu 0.1 O 3 exhibits a lower overpotential, which had an onset potential of 0.195 V and a half-wave potential of −0.224 V, respectively. CaFe 0.9 Cu 0.1 O 3 displays an outstanding four-electron pathway for ORR mechanism and demonstrates superiors corrosion resistance and stability. The MFC with CaFe 0.9 Cu 0.1 O 3 has a greater maximum power density (1090 mW m−3) rather than that of Pt/C cathode (970 mW m−3). This work demonstrated CaFe 0.9 Cu 0.1 O 3 is an economic and efficient cathodic catalyst for MFCs. • Cu-doped double B-site perovskite forms microporous structure. • Cu promotes the combination of Fe–O and O. • CaFe 0.9 Cu 0.1 O 3 shows outstanding and highly stable ORR catalytic performance. • CaFe 0.9 Cu 0.1 O 3 can be used as a highly efficient cathode catalyst in MFCs. [ABSTRACT FROM AUTHOR]