Effect of Platinum particle size and Oxygen pressure on activity of Platinum/Carbon gas diffusion electrodes in high temperature acid medium

摘要

The Platinum/Carbon (Pt/C) gas diffusion electrode was used as cathode instead of the traditional electrode for energy saving electrodeposition of manganese dioxide (MnO_2). This paper studies Pt particle size and oxygen pressure (Po_2) effect on activity of Pt/C gas diffusion electrodes in high temperature acid medium. The Pt nanoparticles evenly distributed on the carbon black surface except the Pt/C-4 and the diameters of the Pt particles size are different (Pt/C-1, Pt/C-2, Pt/C-3, Pt/C-4). The particle sizes of the Pt/C-1, Pt/C-2, Pt/C-3, Pt/C-4 are about 1.6 nm, 2.02 nm, 3.0 nm and 9 nm, respectively. When the loading amount of Pt is the same, the electrode performance of the Pt/C-3 gas-diffusion cathode is better than that of the Pt/C-1, Pt/C-2 and Pt/C-4 gas-diffusion cathode. The open circuit potential, oxygen reduction current of the Pt/C gas diffusion electrode increase with increasing oxygen pressure.