Photoelectrochemical oxidation of 2-mercaptoethanol at the surface of octacyanophthalocyanine thin film electrodes

摘要: Thin films of octacyanophthalocyanine metal complexes (1) on ITO substrates have been studied in photoelectrochemical experiments comparison with tetrapyridotetraazaporphyrinatozinc (2), tetrapyrazinotetraazaporphyrinatozinc (3) and unsubstituted phthalocyaninatozinc (4) contact aqueous redox electrolytes containing 2-mercaptoethanol or hydroquinone. At electrodes the zinc(II) complex 1a at 2 3 current under illumination exceeds that dark by a factor up to five, whereas no significant photocurrent is observed 4. The relative concentrations electrons LUMO (CB) defect-electrons HOMO (VB) are influenced changing electron density within inner ring π-system, leading differences semiconducting properties. Electrodes were investigated further detail. In spite presence thiyl-radicals performed high stability. thiolate anion found be electroactive species. dependence reactant concentration could attributed an adsorption step. A model including charging discharging processes these surface states presented for analysis transients as obtained chopped light beam.