Self‐Humidified Pt Electrocatalyst Fabricated from Hydrophilic Molecules Coating with Enhanced Fuel Cell Performance

Abstract Catalyst layer is essential for fuel cell performance of polymer electrolyte fuel cells (PEFCs) since electrochemical reactions occur and triple phase boundary forms in catalyst layer. Here, we report a self‐humidified platinum (Pt) electrocatalyst, in which the Pt nanoparticles were coated by 2,7‐bis(3,4‐dihydroxyphenethyl)benzo[lmn][3,8]phenanthroline‐1,3,6,8‐tetraone (NPDA) and the surfaces of Pt nanoparticles are tuned to be hydrophilic, which could adsorb the generated water and enhanced the fuel cell performance under non‐humidified operation condition. Due to the hydrophilic surfaces of Pt nanoparticles, power density of self‐humidified Pt electrocatalyst rapidly reached the maximum power density (700 mW cm −2 ) without any humidification; in contrast, with hydrophobic surface, power density was only (525 mW cm −2 ). Meanwhile, the fabricated electrocatalyst exhibits higher durability and could work under real fuel cell operation condition for 18,000 h with only 9 % decay in electrochemical surface area.