CeO<sub>2</sub>-NiO-rGO as a nano-electrocatalyst for methanol electro-oxidation
Mohammad Bagher Askari, Mohammad Taghi Tourchi Moghadam, Sadegh Azizi, Seyed Rouhollah Samareh Hashemi, Mohsen Shojaeifar, Antonio Di Bartolomeo
Abstract
Abstract This study provides the methanol oxidation capability of two nanocatalysts, CeO 2 -NiO (CN) and CeO 2 -NiO-rGO (CNR), synthesized by a cost-effective hydrothermal method. The synergistic effect of compositing CeO 2 -NiO with reduced graphene oxide was evaluated. These synergic effect makes a good electrochemical active surface area and suitable electrical conductivity for catalyst. In addition, rGO with good electrical conductivity revealed considerable improvement in the methanol oxidation reaction performance of the catalyst. The cyclic stability measurements of CeO 2 -NiO-rGO showed a high retention ability of 96% in 500 consecutive cyclic voltammetry cycles, while the stability of CeO 2 -NiO in the same number of cycles is about 93%. The complementary methanol oxidation process results indicated an oxidation current density up to 49.5 and 68.5 mA cm −2 for CN and CNR at a scan rate of 20 mV s −1 , respectively. The proposed catalyst can be considered as an attractive, stable, and inexpensive candidate in the field of methanol oxidation to use in methanol fuel cells.