Fabrication of an electrode-viologen-hydrogenase heterogeneous system and the electrochemical hydrogen evolution

An indium tin oxide (ITO) electrode was chemically modified by one layer of viologen (VIO) derivative, which possessed a persistent and reproducible e lectrochemical response. A monolayer of a thermal stable hydrogenase from T hiocapsa roseopersicina was stabilized on a synthesized poly-L-lysine subph ase surface and transferred onto the electrode for fabrication of an ITO-VI O-hydrogenase heterogeneous system. Electrochemical properties of both the ITO-VIO monolayer and the heterogeneous ITO-VIO-hydrogenase system have bee n investigated. Hydrogen evolution could be measured by potentiostating the VIO-hydrogenase-covered ITO electrode to "electroplate" [(VIO')(n)](surf), and a large increase in hydrogen evolution was observed the possible elect ron transfer process.