A comparative study of the use of PtRu nanoparticles supported on hierarchical porous carbons with different pore sizes for CO2 production efficiency during methanol electro-oxidation was performed by Differential Electrochemical Mass Spectrometry. The supported catalyst PtRu/HPC400 presented an ESA of 82.56 m2 g−1 lower than the commercial catalyst PtRu/E-tek (107.2 m2 g−1); however, it has higher performance for methanol electro-oxidation. Methanol conversion efficiency reaches values higher than PtRu/E-tek commercial catalyst, 93.17% for PtRu/HPC400 versus 41.36% for PtRu/E-tek, under potentiodynamic conditions. The hierarchical porous carbons interconnected channels improve the mass transport process.