Effect of deposition time on photoelectrochemical performance of chemically grown Bi2Se3-sensitized TiO2 nanostructure solar cells

Abstract

This paper explore the ability of bismuth selenide (Bi2Se3) as an alternative light sensitizer for photoelectrochemical (PEC) solar cell. Herein, we applied novel chemical route, namely, chemical bath deposition (CBD) for growth of Bi2Se3 nanoparticles over spin-coated TiO2 at room temperature. The structural, surface morphological, and optical properties of TiO2/Bi2Se3 films are systematically studied. The deposition time for the growth of Bi2Se3 using CBD can enable to tune the size of Bi2Se3 nanoparticles over porous TiO2 which significantly influences the physical properties of resultant heterostructure. The potential of Bi2Se3 nanoparticles in PEC solar cell is demonstrated by preparing FTO|TiO2|Bi2Se3|polysulphide electrolyte|carbon-coated FTO device structure and tested with current density–voltage (J-V) and electrochemical impedance spectroscopy (EIS) measurements. The result presented in this study established that the photoconversion efficiency and electron life time of device are affected by deposition time for Bi2Se3 using CBD. The J-V measurement done with above-proposed devices shows maximum photoconversion efficiency around 0.152% for 20 min deposited Bi2Se3.