Green synthesis of gallic acid–capped gold nanoparticles as novel electro-catalyst for electro-oxidation of ethylene glycol in alkaline media

This study reports the synthesis of gallic acid–capped gold nanoparticles (GA-AuNPs) through a simple, inexpensive, and environmentally friendly chemical method and their applications in fuel cells. In the proposed method, gallic acid acts as the reducing agent and stabilizer. The studies showed that the size and distribution of AuNPs could be controlled by controlling the molar ratio of gallic acid to gold ions. The prepared GA-AuNPs were used as an electro-catalyst to oxidize ethylene glycol (EG) molecules on the glassy carbon electrode (GCE) surface in alkaline media. The results showed that the modified electrode using GA-AuNPs with a 1:1 M ratio has a higher electrochemical active surface area (ECSA); therefore, it has improved electro-catalytic activity, increased stability, and durability for EG oxidation compared to other ratios of GA/Au and even to the bare Au electrode.