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.