Electro-oxidation of coal on NiO and/or Co3O4 modified TiO2/Pt electrodes

A TiO2/Pt based electrode exhibited better activity for the oxidation of coal in a basic system compared to Ti/Pt, TiO2–Cu/Pt and pure metal electrodes. The surface morphologies and composition of the electrodes were studied by SEM and XRD, respectively. Linear sweep voltammetry was employed to investigate the catalytic effects of electrodes, and the product of coal oxidization was determined by a gas collection test. The TiO2/Pt electrodes that were modified with NiO and/or Co3O4 exhibited higher average currents and a lower decrease in mass during electrolysis compared to the other electrodes; this finding indicated that NiO and Co3O4 play important roles as catalysts.

► Electrodes based on porous TiO2/Pt substrate were employed for the electro-oxidation of coal in basic electrolyte system.
► TiO2/Pt electrodes modified with NiO and/or Co3O4 catalysts show great activity in the electro-oxidation of coal.
► Hydroxyl radical generated by the metal oxide plays important role in the reaction.