Highly reversal-tolerant anodes using Ti4O7-supported platinum with a very small amount of water-splitting catalyst

Gross fuel starvation can seriously damage the anode of polymer electrolyte fuel cells (PEFCs) due to the exceptionally high anodic potential induced by oxygen evolution and carbon corrosion reactions to generate protons, instead of hydrogen oxidation. In this report, we describe a highly effective reversal-tolerant anode catalyst (RTA) based on Pt/Ti4O7 with a very small amount of Ir. A membrane electrode assembly (MEA) using a Pt/Ti4O7 RTA including 0.04 mgIr cm−2 shows almost no performance loss even after severe cell reversal. This is in clear contrast with the results obtained with an Pt/C RTA including the same amount of Ir, for which a significant voltage loss is observed after a cell reversal test. Moreover, the reversal-tolerance of Pt/Ti4O7 RTA is considerably high even with a very small amount of Ir, as low as 0.014 mgIr cm−2. An Ir/Ti4O7 based anode also shows superior RTA property as well as the mitigation of start-up/shut-down degradation due to the limited activity of Ir for the oxygen reduction reaction. A post-mortem analysis of the tested MEA confirmed that Pt/Ti4O7 RTA alleviates damage to not only the catalyst layer but also the micro porous layer, which leads to a better RTA property for the Pt/Ti4O7. [Display omitted] •Reversal tolerant anodes (RTAs) based on Ti4O7 support are proposed.•Even with 0.014 mgIr cm−2, Pt/Ti4O7 RTA shows negligible voltage loss.•Pt/Ti4O7 RTAs show higher voltage stability than Pt/C and Pt/GKB RTAs.•Ir/Ti4O7 RTA is also effective for mitigation of start-up/shut-down damages.•Ti4O7 support is advantageous for improving RTA property with smaller amount of Ir.