Hydrogen production using a photoelectrocatalytic–enzymatic hybrid system

In this paper the development of a novel photoelectrocatalytic–enzymatic hybrid system for hydrogen production is presented. Together with hydrogen production in the cathode compartment of a photoelectrochemical cell, the destruction of the insecticide Imidacloprid, which acts as a model pollutant, will take place in the anodic compartment due to the photoelectrocatalytic effect. The photogenerated electrons in the Ti/TiO2 anode are transferred to the cathode where the hydrogenase enzyme derived from the algae Chlamydomonas reinhardtii, catalyzes the reduction of the H+ species to H2. The optimization of both processes is being investigated for the purposes of this paper. 45% reduction in the organic carbon content of the Imidacloprid molecule was photoelectrocatalytically possible at the anode, while 21.3 μmol H2 per liter of the algae culture was simultaneously produced at the cathode over a period of 45 min. The production of the hydrogenase enzyme under photoheterotrophic and sulphur deprived conditions was confirmed by reverse transcription-polymerase chain reaction (RT-PCR).

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► Photoelectrocatalytic degradation of Imidacloprid under simultaneously enzymatic production of hydrogen.
► Hydrogen production by algae cells containing the enzyme Chlamydomonas reinhardtii.
► Existence of a linear relationship between produced hydrogen and enzyme activity.