Fig. 5. Photocurrent action spectra of the Ru–ZnP/TiO2/FTO (black), Ru-ref + ZnP-ref/TiO2/FTO (blue) and ZnP-ref/TiO2/FTO electrodes (red) with a TiO2 thickness of 6 μm. Dashed line depicts the light-harvesting efficiency of the Ru–ZnP/TiO2/FTO electrode. Conditions: external bias: –0.2 vs. NHE, electrolyte: PB (0.1 M, initial pH 7.3); and scan rate: 2 nm s–1 from 400 nm to 800 nm.
