High-Performance Visible-Light-Driven Ag–gC3N4/Pt Photoelectrocatalysts for Methanol Oxidation

The world’s demand for energy has increased dramatically over the last few decades, and will continue to do so. Therefore, it is urgent to find alternative energy sources and perhaps unconventional way of energy conversion with much improved energy efficiency [1]. Fuel cells have received increasing attention because of their high energy conversion efficiency and environmental affinity [2]. Among different type of fuel cells, direct alcohol fuel cells (DAFCs) were attracting increasing interest as a compact power sources for portable applications, mainly due to the relatively simple handling, storage, and transportation of the fuel [3]. Among fuel cells, the direct methanol fuel cell (DMFC) is one of the most attractive ones because of high energy conversion efficiency and low environmental intrusion and without a reformer [4-7].Traditional electrocatalysts together with optically active semiconductors are selected as the promising catalysts for the improvement of anodic reactions. In order to fabricate the modified electrode, firstly, Pt nanoparticles were electrodeposited on the surface of FTO electrode. Then, graphite carbon nitride (gC3N4) decorated with silver nanoparticles (Ag NPs) was casted on the surface of Pt/FTO electrode. The Ag–gC3N4/Pt/FTO electrode displayed much higher catalytic properties for methanol oxidation compared to the Pt/FTO electrode. Interesting, when the modified electrode was upon visible light irradiation, both the catalytic activities and stabilities were improved greatly. The synergistic effect of Pt catalyst and photo-irradiation promotes the electrocatalytic performance and stability. Our result provides a new insight into developing highly efficient photoelectrocatalyst for application in direct methanol fuel cells in the presence of visible light illumination.