Photoelectrochemical decomposition of amino acids on a TiO2/OTE particulate film electrode

The photoelectrochemical degradation of amino acids and derivatives such as glutamic acid, glutamine, glutaric acid, lysine, beta-alanine, 8-aminooctanoic acid and phenylalanine has been examined on an irradiated TiO2/OTE particulate film electrode. The photooxidative disappearance of the substrates ultimately transforms the nitrogen into NO3- and NH3 (as ammonium ions under our conditions), whereas the carbonaceous residues are converted into CO2. Variations in photocurrent were observed during the temporal course of the photodegradative process. The rates of conversion and the quantity of degraded products depend on the external applied bias and appear to be closely related to the molecular structure of the substrates. A photoelectrochemical degradative pathway is discussed briefly on the basis of the experimental observations. (C) 1997 Elsevier Science S.A.