Silica-facilitated proton transfer for high-temperature proton-exchange membrane fuel cells

High-temperature proton-exchange membrane fuel cells (HT-PEMFCs) have shown a broad prospect of applications due to the enhanced reaction kinetics and simplified supporting system. However, the proton conductor, phosphoric acid, tends to poison the active sites of Pt, resulting in high Pt consumption. Herein, Pt nanoparticles anchored on SiO2-modified carbon nanotubes (CNT@SiO2-Pt) are prepared as high-performance cathode catalysts for HT-PEMFCs. The SiO2 in CNT@SiO2-Pt can induce the adsorption of phosphoric acid transferring from Pt active sites in the catalytic layer, avoiding the poisoning of the Pt, and the phosphate fixed by SiO2 provide a high-speed proton conduction highway for oxygen reduction reactions. Accordingly, The CNT@SiO2-Pt cathode achieve superior power density of 765 mW cm−2 (160 °C) and 1,061 mW cm−2 (220 °C) due to the rapid proton-coupled electron process and outstanding stability in HT-PEMFCs. This result provides a new road to resolve the phosphate poisoning for the commercialization of HT-PEMFCs.