Achievement of an efficient oxygen reduction electrocatalyst based on carbon boosted with MnOx/MnCo2O4 with excellent electrocatalytic activity in neutral media

Abstract

In the current research, a manganese and cobalt oxides-based nanocatalyst was developed which was used to make an efficient cathode electrode for fuel cells. The nano MnO_x/MnCo₂O₄ was synthesized through a hydrothermal procedure followed by sintering at 500–600 °C. X-ray diffraction and scanning electron microscopy besides electrochemical techniques were applied for the characterization of the synthesized nanocatalyst. The carbon black type Vulcan (XC-72R) and PTFE were used to prepare the active reaction material of the cathode electrode named carbon paste (CP). Loading of the synthesized nano MnO_x/MnCo₂O₄ on CP was optimized in a weight ratio of 10–90% for the oxygen reduction process in neutral conditions. The best performance was gained for the 50 W% MnO_x/MnCo₂O₄ loaded CP, whose active surface area was twice the bare CP. The values of the exchange current density of the ORR obtained by electrode containing 50 W% MnO_x/MnCo₂O₄ was calculated as 0.12 mA/cm². The low price, good catalytic efficiency, and cyclic stability of the MnO_x/MnCo₂O₄ nanocatalyst compared to the commercial platinum-based catalysts confirm its ability to develop fuel cell electrodes.