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A facile, rapid, green, and novel clean synthesis of advanced RGO/bimetallic Pt-Pd alloy/CeO2nanocomposite electrocatalyst with the enhanced electrocatalytic performance of methanol oxidation reaction (MOR) has been successfully carried out through a one-step hydrothermal-assisted formic acid reduction reaction without applying any template or surfactant. The as-prepared electrocatalysts were extensively characterized by X-ray Powder Diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS), Energy Dispersive X-ray Spectroscopy (EDX), High-Resolution Transmission Electron Microscopy (HRTEM), and Field-Emission Scanning Electron Microscopy (FESEM) to confirm the formation, deposition and homogenous distribution of Pt-Pd alloy and CeO2nanoparticles (NPs) on the surface of RGO. Meanwhile, the electrocatalytic activity and the long-term stability performance of the as-prepared electrocatalysts towards MOR were employed by cyclic voltammogram and chronoamperometry, respectively. Noticeably, the as-prepared RGO/bimetallic Pt-Pd alloy/CeO2nanocomposite electrocatalyst presented very outstanding electrocatalytic performance with higher maximum forward peak current density (69.82 mA cm−2) than those of RGO/monometallic Pt/CeO2(23.81 mA cm−2) and RGO/monometallic Pd/CeO2(1.39 mA cm−2) toward MOR in acidic medium denoting to the large surface area and excellent conductivity of RGO, homogenous distribution of Pt-Pd alloy electrocatalyst as well as a synergistic effect between Pt-Pd alloy NPs, RGO, and CeO2NPs. Moreover, the RGO/bimetallic Pt-Pd alloy/CeO2electrocatalyst also possesses excellent stability and exceptional poisoning tolerance through the advantages of utilizing Pt-Pd alloy NPs and the synergistic effect of CeO2NPs. Therefore, this study may open a new facile route with the convenient experimental procedure, clean, reasonable cost, easy to handle, no time consuming, and easy to scale-up for the large quantity production of an advanced anode electrocatalyst for direct methanol fuel cell application.

The efficient synthesis of reduced graphene oxide (RGO) nanosheets via chemical reduction process of exfoliated graphene oxide (GO) nanosheets was performed by introducing sodium oxalate (Na2C2O4) as a reducing agent. To study the effects of the reduction time on the synthesized RGO, the GO was reduced within -1/2, 1 and 2 h for RGO-1, RGO-2 and RGO-3, respectively. The C/O atomic ratio of the synthesized RGO-3 has increased from 2.16 to 6.32 after reduction as determined by X-ray photoelectron spectroscopy (XPS). The morphology analysis of the RGO-3 was determined by high-resolution transmission electron microscopy (HRTEM) almost revealed the formation of single layer. The number of RGO layers decreases as the time of the reduction increases. Based on these analysis results, sodium oxalate plays an important role in the efficient removal of the oxygen containing groups in the GO to produce high quality of RGO.