Self-humidifying manganese oxide-supported Pt electrocatalysts for highly-durable PEM fuel cells

In this paper, we report on the synthesis and function of self-humidifying nature of manganese oxide supported platinum (Pt/MnxOx) electrocatalyst under dry gas condition in proton exchange membrane fuel cells (PEMFC) with excellent electrochemical stability, long-term durability and remarkable fuel cell performance. The high-surface area nano-petal shaped manganese oxide (MnxOx) clusters are synthesized by anodic deposition and the Platinum (Pt) nanoparticles are electrodeposited on diffusion layer (GDL) having two-layers of MnxOx coating. The morphology and self-humidifying nature of Pt/MnxOx were extensively studied through HR-SEM, HR-TEM, XPS, XRD, and water uptake studies. The electrochemical stability and long-term durability were investigated through cyclic voltammetry (CV) studies and single cell fuel cell performance. The MEAs using the spherical clusters of clump-like Pt/MnxOx exhibited a peak power of 0.65 W/cm2 at 0.48 V under dry gas condition without humidification. Also, the fuel cell delivered stable power output at a constant current density of 0.8 A/cm2 for about 150 h with a negligible potential drop of 26 μV h−1. The long-term durability, excellent electrochemical activity and self-humidifying nature of Pt/MnxOx may be attributed to the formation of hydroxyl groups on Pt/MnxOxwhich facilitates the proton conductivity.