Photocatalytic Synthesis of Ultrafine Pt Electrocatalysts with High Stability Using TiO2‐Decorated N‐Doped Carbon as Composite Support

Abstract

AbstractCommercial Pt/C (Com. Pt/C) electrocatalysts are considered optimal for oxygen reduction and hydrogen evolution reactions (ORR and HER). However, their high Pt content and poor stability restrict their large‐scale application. In this study, photocatalytic synthesis was used to reduce ultrafine Pt nanoparticles in‐situ on a composite support of TiO2‐decorated nitrogen‐doped carbon (TiO2−NC). The nitrogen‐doped carbon had a large surface area and electronic effects that ensured the uniform dispersion of TiO2 nanoparticles to form a highly photoactive and stable support. TiO2−NC served as a composite support that enhanced the dispersibility and stability of ultrafine Pt electrocatalyst, owing to the presence of N sites and the strong metal‐support interaction. Relative to Com. Pt/C, the as‐obtained Pt/TiO2−NC had positive shifts of 44 and 10 mV in the ORR half‐wave potential and HER overpotential at −10 mA cm−2, respectively. After an accelerated durability test, Pt/TiO2−NC had lower losses in electrochemical specific area (0.7 %) and electrocatalytic activity (0 mV shift) than Com. Pt/C (25.6 %, 22 mV shift). These results indicate that the developed strategy enabled the facile synthesis and stabilization of ultrafine Pt nanoparticles, which improved the utilization efficiency and long‐term stability of Pt‐based electrocatalysts.