Graphitic mesoporous carbon xerogel as an effective catalyst support for oxygen reduction reaction

• A graphitic mesoporous carbon xerogel (GMCX) support was prepared through a facile synthesis process.
• Pt nanoparticles were highly dispersed on the surface of GMCX with the average size of 2.8 nm.
• Pt/GMCX has high catalytic activity and good durability for oxygen reduction reaction.

Graphitic mesoporous carbon xerogel (GMCX) with high surface area and comparable mesoporous structure is prepared via a sol–gel process with cobalt acetate, followed by the subsequent pyrolysis in nitrogen flow at 1800 °C. 20 wt.% Pt/GMCX catalyst is synthesized using the as-prepared GMCX powder as support. The results of X-ray diffraction (XRD) and transmission electron microscopy (TEM) characterizations for Pt/GMCX indicate that Pt nanoparticles dispersed on GMCX have a much smaller average nanoparticle size and narrower size distribution than Pt nanoparticles grown on commercial XC-72 carbon black and GCX powder which we reported before. The results of linear sweep voltammetry (LSV) test demonstrate that the Pt/GMCX catalyst exhibits a higher oxygen reduction reaction (ORR) electrocatalytic activity than commercial Pt/C and Pt/GCX. The corrosion resistance of the catalysts was evaluated by potential cycling accelerated aging test (AAT). Pt/GMCX catalyst exhibits very nearly the same Pt electrochemical active surface area (EASA) retention as Pt/GCX (53.3% for Pt/GMCX and 53.0% for Pt/GCX), which is higher than that of commercial Pt/C (39.2%). Combined with its facile synthesis process, GMCX powder is a promising substitute for commercial Pt electrocatalyst support in achieving high catalytic activity and good durability for ORR.