Solar hydrogen production using semiconductor septum ( n- [formula omitted] and n- [formula omitted]) electrode based photoelectrochemical solar cells

Abstract

In the present study, photoelectrochemical and hydrogen evolution characteristics of CdSe Ti and TiO 2 Ti based semiconductor-septum photoelectrochemical (SC-SEP, PEC) solar cell have been studied. The SC-SEP cell in the configuration of SCE, l M 3S//CdSe/Ti//5 M H 2SO 4, Pt(W), Pt(C), gave power output of 0.62 V and 11 mA cm −2, whereas the conventional Pt, 1 M 3S//CdSe/Ti, PEC cell gives power output of 0.64 V and 6 mA cm −2. The hydrogen evolution characteristics of SCE, l M 3S//CdSe/Ti//5 M H 2SO 4, Pt(W), Pt(C), exhibited a rate of 1.0 to 1.5 1 h −1 m −2 under an illumination intensity of 80 mW cm −2. The TiO 2 Ti septum based SC-SEP solar cell in the configuration of SCE, 1 M NaOH//TiO 2/Ti//5 M H 2SO 4, Pt(W), Pt(C), gives power output of 0.74 V and 14.5 mA cm −2 whereas the conventional Pt, 1 M NaOH//TiO 2/Ti, PEC solar cell gives power output of 0.7 V and 5 mA cm −2. The hydrogen evolution characteristics of TiO 2/Ti based SC-SEP cell measured in the configuration of SCE, 1 M NaOH//TiO 2/Ti//5 M H 2SO 4, Pt(W), Pt(C), gave a hydrogen evolution rate of 10–15 1 h −1 m −2 under an illumination intensity of 450 mW cm −2. It has been shown in the present investigation that TiO 2 Ti based SC-SEP solar cell is more stable and gives higher rate of hydrogen production compared to the CdSe Ti based SC-SEP cell. Further studies to optimize the stability and other conditions for the production of solar hydrogen using these SC-SEP solar cells have been outlined.