Enhanced Hydrogen Production during Electro‐oxidation of Ethanol using Plasmonic Gold Nanoparticles

Electrochemical reforming of alkaline ethanol through nonfossil fuel resources is an attractive single-step method at room temperature and pressure for hydrogen production. Herein, solar panels are used to generate and allow low-voltage current to flow into screen-printed electrodes with milliscale spacing to produce a high-intensity electric field, engendering electrolysis of alkaline ethanol into H-2. The introduction of gold nanoparticles (Au NPs) with diameters between 20 and 100 nm into the electrolyte results in an enhanced capacity of the electrolyzer to produce H-2 under an illumination equivalent to solar irradiance. The plasmonic Au NPs facilitate faster electro-oxidation of the alkaline ethanol. The solar irradiance serves dual purposes-generation of a high-intensity electric field in the electrolyte and plasmonic effects for a faster rate of H-2 production. The results show current densities as high as 135, 240, and 118 A m(-2) with independent variations in sizes of Au NPs, wavelength of solar radiation, and irradiance of light, respectively. Furthermore, a high Faradaic efficiency of 82% is obtained for the electrolyte solution containing Au NPs of size 50 nm. Integration of multiple screen-printed electrodes shows further enhancement of H-2 throughput, leaving a niche for the prototype to scale-up H-2 production.