A comparative study of CO catalytic oxidation on Pd-anchored graphene oxide and Pd-embedded vacancy graphene

The catalytic oxidation of CO on Pd-anchored graphene oxide (Pd-GO) and Pd-embedded vacancy graphene (Pd-VG) is investigated by density functional theory calculations. The results validate both Pd-GO and Pd-VG show good catalytic performance for CO oxidation. Meanwhile, the more positive charge for Pd adatom and the lower reaction energy barrier make Pd-VG system slightly superior than Pd-GO system in catalytic performance. The reaction proceeds via Langmuir–Hinshelwood mechanism with a two-step route (CO + O2 → OOCO → CO2 + O), followed by the Eley–Rideal mechanism (CO + O → CO2). However, the synthesis of Pd-VG is more difficult in experiments compared with the readily available Pd-GO. Hence, graphene oxide may serve as the alternative substrate to deposit Pd nanoparticles.