Authors: K.R. Wu, C.H. Hung, C.W. Yeh, C.C. Wang, T.P. Cho
Affilation: National Kaohsiung Marine University, Taiwan
Pages: 796 - 799
Keywords: solar hydrogen, titanium dioxide, indium tin oxide, photoelectrochemical
In this study, a nitrogen/carbon-codoped indium tin oxide (N,C-ITO) film is deposited on unheated ITO glass substrate. Thereafter, a titanium dioxide (TiO2) film is grown on the N,C-ITO layer to be a layered TiO2/N,C-ITO (Ti/TO) film electrode. Under 1.0 AM simulated sunlight irradiation and 1.5 V applied potential, the layered Ti/TO film electrode has the highest photocurrent density of 0.42 mA/cm2 and hydrogen yield rate of 110.0 μmol/cm2-h. Comparatively, the counter N,C-ITO electrode has a photocurrent density of 0.35 mA/cm2 and a hydrogen yield rate of 95 μmol/cm2-h, respectively. However, the counterpart TiO2 electrode with the same film thickness exhibits a photocurrent density of 0.09 mA/cm2 and a hydrogen yield rate of 25.0 μmol/cm2-h, respectively. The relatively high photoactivity response of the counter N,C-ITO electrode is the synergetic effect of N,C-codping on band gap narrowing and photosensitizing. The overlaid TiO2 layer enhances not only the photocurrent response at entire applied potentials, but also the flat band potential; shifted from about -0.82 to -0.91 V. The results imply that the layered Ti/TO film electrode can potentially serve a photoelectrode for solar hydrogen production.