The Pt/g-C3N4-CNS catalyst via in situ synthesis process with excellent performance for methanol electrocatalytic oxidation reaction

Abstract

This study reports the preparation of a graphite carbon nitride (C₃N₄) and carbon nanosheet (CNS) composite support (g-C₃N₄-CNS) by in situ synthesis (IS), and the effect of the Pt-based catalyst on methanol electrocatalytic oxidation (MOR) was investigated. The experiment proved that Pt/IS-g-C₃N₄-CNS has higher MOR catalytic performance and stability than Pt/MS-g-C₃N₄-CNS, which was prepared by mechanical synthesis. Notably, the Pt/IS-g-C₃N₄-CNS catalyst has the best electrocatalytic activity. The current density of the Pt/IS-g-C₃N₄-CNS catalyst is 105.1 mA cm⁻², and its chronoamperometry current loss rate is 66.4%, which is much higher than that of Pt/MS-g-C₃N₄-CNS. Through BET, TEM, XRD, and XPS characterization, it was found that the in situ synthesized g-C₃N₄-CNS composite support has stronger interaction, larger specific surface area, and higher pyridine nitrogen and pyrrole nitrogen content, which jointly promote the dispersion of Pt nanoparticles and present superior electrocatalytic performance for the MOR reaction.