Low platinum alloy catalyst PtCo3 obtaining high catalytic activity and stability with great water and CO2 resistance for catalytic oxidation of toluene

•The PtCo3 nanoparticles were synthesized by the organic phase reduction method.•High toluene catalytic activity and thermal stability were obtained.•Great water and CO2 resistance for catalytic oxidation of toluene.•The PtCo3-C catalyst is easier to adsorb toluene than H2O and CO2 based on the adsorption energy calculation.