On the electrooxidation of glucose on gold: Towards an electrochemical glucaric acid production as value-added chemical

The electrocatalytic oxidation of glucose to value-added chemicals, such as glucaric acid, has gathered increased interest in recent years. Glucose oxidation is a promising process which has the potential to contribute to establishing renewable resources as alternatives to fossil carbon sources. Herein, we present rotating disk electrode (RDE) studies on polycrystalline gold surfaces and subsequent Koutecký-Levich analysis as a benchmark to expand the understanding of reaction kinetics and competition between glucose, reaction intermediates and OH− at the catalyst surface. Based on the obtained results it follows that the glucose oxidation reaction (GOR) is predominately mass-transport controlled. Combining electrochemical studies and Raman spectroscopy, it is shown that increasing glucose concentrations lead to a delayed oxidation of the gold catalyst surface, presumably by increased consumption rates of Au-hydroxide species.