Experimental insight into the performance characteristics of Ni-mesh semiconductor photo-electrochemical cells

The performance characteristics of two photo-electrochemical cells with different cell configurations were investigated at 25 degrees C and within the illumination range of 70-100 W/m(2). These cells included a jacketed single cell (JSC) and a jacketed two-compartment cell (JTC). Ni-mesh was used as a counter electrode and as a backing material for semiconductor electrodes. Semiconductor electrodes were prepared by silk-screen painting technique using TiO2, WO3, PbO, Sb2S3, ZnO, Al2O3 or CuO powder mixed with Teflon. The electrolyte contained aqueous methylene blue (MB) and Fe (II)/Fe(III) compounds. Voltage-current characteristics of the cells were measured at 25 degrees C. Energy conversion efficiencies were calculated. A best-performing cell was selected from each cell configuration. The effects of Ni-mesh, semiconductor properties, and electrolyte modification on cell performance were studied. Experimental observations are compared with those in the literature, and the performance of each cell configuration is discussed. The best performance was obtained from Ni-TiO2-MB/MB, Fe(II)//MB, Fe(II)/Ni-C cell configuration with 13% efficiency from JTC, Ni-PbO/MB, Fe(II)/Ni cell configuration with 24% effciency from JSC. (C) 2000 Elsevier Science B.V. All rights reserved.