Enhanced efficiency of bifacial and back-illuminated Ti foil based flexible dye-sensitized solar cells by decoration of mesoporous SiO2 layer on TiO2 anode

The present study focuses on enhancing the efficiency of bifacial and back-illuminated dye-sensitized solar cells (DSCs) by incorporating SiO2 mesoporous layer on TiO2 electrode. The performance of DSCs is investigated by UVevisible spectroscopy, incident photon conversion efficiency (IPCE) and electrochemical impedance spectroscopy (EIS). It is observed that the current ratio of back- to front-DSC increases with the increase in the thickness of SiO2 layer, which in turn influences the incident light to dyed-TiO2 electrode, especially in the wavelength of 400e600 nm. The Ti foil based flexible small (0.28 cm2) and sub-module (5 cm � 10 cm) DSCs having this modification show high conversion efficiencies of 6.76 and 5.54% respectively under 100 mW cm�2 (AM 1.5)