In this study, Ag-Pt alloy on carbon support was synthesized with a simple wet chemical precipitation method and used as biocidal cathode catalyst in a microbial fuel cell (MFC). X-ray diffraction analysis revealed cubic symmetry of Ag3Pt alloy could be synthesized, which was found to be homogenously distributed over carbon skeleton. Cyclic voltammetry result suggested Ag3Pt as an excellent oxygen reduction reaction catalyst and compared to C-Pt, it could promote higher reduction current with lower activation over potential. Upon using Ag3Pt on cathode of MFC, there was no significant sign of biofouling noticed on the cathode or membrane surface over 40 days of operation; whereas a 225 am and 193 mu m thick lawn of biofouling was observed on control and C-Pt catalyzed cathodes, respectively, causing severe current depletion. Moreover, MFC with Ag3Pt catalyzed cathode could recover substantially higher coulombic efficiency of 60.4% and voltage of 76 mV compared to other MFCs, which was consistent throughout 40 days of operation. (C) 2018 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.