Open-textured polydopamine-reduced graphene oxide loaded Pd nanoparticles with high-efficiency electrocatalytic performance toward ethylene glycol oxidation

A qualified anode catalyst is the crucial component for one direct alcohol fuel cell. To facilitate the practical application of direct ethylene glycol fuel cells (DEGFCs), it holds significant importance to develop an anode catalyst with low cost, relatively high catalytic activity and reliable stability toward ethylene glycol oxidation reaction (EGOR). In this study, an in-situ polymerization method was employed to synthesize polydopamine (PDA)-functionalized reduced graphene oxide (rGO) as an efficient support for palladium nanoparticles (Pd NPs), ultimately resulting in the fabrication of a high performance Pd/PDA-rGO catalyst. Multiple physical characterization techniques confirm the consistent distribution of Pd NPs on the porous and fluffy PDA-rGO compound with open-textured structure. In the catalyst, rGO functions as a conductive component to boost the electronic conductivity of PDA and facilitates the formation of the wrinkled structure. Meanwhile, PDA granules can promote proton conductivity and prevent the aggregation of rGO. The unique morphological features of granular PDA and wrinkled rGO synergistically promote uniform Pd NPs distribution and improve their catalytic performance. The electrochemical evaluation of the EGOR was performed and it is found that the optimized Pd/PDA-rGO catalyst has remarkable mass activity and specific activity, which reached 3391.7 mA mg Pd −1 and 22.2 mA cm −2 . It also shows improved intrinsic activity, with a conversion frequency of 4.6 s −1 and excellent stability. The mass activity of Pd/PDA-rGO is about 8 times that of commercial Pd/C. This work establishes PDA-rGO as an ideal catalyst support and provides a strategy for designing advanced electrocatalysts.