Electrooxidation of glycerol and methanol on gold

Abstract: Burning of fossil fuels leads to excess CO2 in the atmosphere, causing global warming, threatening civilisation and ecosystems worldwide. As a step in making the society fossil-independent, we need to replace oil, coal, and gas in the transportation sector with fuels originating from sustainable energy. Biodiesel is one such option, from which we get glycerol as a byproduct. With the help of electrooxidation, we can use glycerol as a feedstock to extract hydrogen gas, which may be for upgrading biofuels or used in proton exchange membrane (PEM) fuel cells. Methanol is another possible fuel in so called direct methanol fuel cells (DMFC), which raises the interest for studying methanol electrooxidation. In this work, we study glycerol and methanol electrooxidation on gold. We use density functional theory, and verification by cyclic voltammetry, to study thermodynamics of reaction conditions and mechanisms for the electrooxidation mechanisms. Long range dispersion (van der Waals), which have been neglected in computations until recently, is investigated by assessing van der Waals exchange-correlation functionals. Furthermore, microsolvent effects are investigated by inclusion of explicit water molecules.