Facile preparation of mesoporous graphenes by the sacrificial template approach for direct methanol fuel cell application

Abstract

Mesoporous graphenes (MGs) were synthesized via a template-assisted pyrolysis approach and employed to fabricate a cathodic diffusion layer for direct methanol fuel cell (DMFC) application. Phenolic polymer-ammonium oleate supramolecular aggregates that formed by weak acid–base interaction induced self-assembly resulted in a solid carbon source. Layered graphitic carbon nitrides (g-C₃N₄) created under high temperature and a nitrogen gas environment provided the sacrificial template. The MGs were shown to have a specific mesopore surface area of 265.9 m² g⁻¹ with large bimodal mesopore diameters of approximately 4 and 10 nm. Mesopores were generated by the in situ formation and decomposition of a g-C₃N₄ template. The passive DMFC fabricated by the use of MGs in the cathodic diffusion layer demonstrated a peak power density of 32.9 mW cm⁻², which is approximately 1.2 times higher than that with Vulcan XC-72R carbon black. The outstanding characteristics of MGs as a material that can be used as a porous diffusion layer for DMFCs verify the great potential for use in energy-related fields.