Cu2AgInS4 quantum dot sensitized zinc doped Titania nanoparticles film as the high efficient photoanode for photovoltaic cells

Abstract

In this work, Cu, Ag, In, and S based qu aternary quantum dots (Cu2AgInS4 QDs) were synthesized by a hot-injection method, and Zinc doped (0, 1, and 2 wt%) Titania nanoparticles (Zn-TiO2 NPs) were synthesized by a sol-gel method. The synthesized QDs were anchored onto Zn-TiO2 NPs film through a linker-based assembly method to form Cu2AgInS4 QDs/Zn-TiO2 NPs to use as the photoanodes for Quantum dot sensitized solar cells (QDSCs). The physio-chemical behavior of the Cu2AgInS4 QDs, Zn-TiO2 NPs, and Cu2AgInS4 QDs/Zn-TiO2 photoanodes was examined by various spectroscopic analyses. Optical analysis of the fabricated photoanodes revealed that Cu2AgInS4 QDs/Zn-TiO2 NPs photoanode has a high redshift of light absorbance than Zn-TiO2 NPs. Moreover, due to the proper band alignment of Cu2AgInS4 QDs and 2 wt% Zn-TiO2 NPs, Cu2AgInS4 QDs/Zn-TiO2 NPs has high electron transfer ability than Cu2AgInS4 QDs/TiO2 NPs. On the other hand, the electrochemical impedance analysis confirms that Cu2AgInS4 QDs/Zn-TiO2 photoanode has lower charge transfer resistance (9.53 Ω) with high photocatalytic behavior than that of Cu2AgInS4 QDs/ TiO2 NPs as the photoanode. Hence Cu2AgInS4 QDs/Zn-TiO2 NPs photoanode based QDSC shows 36% improvement in the photoconversion efficiency (5.43%) than that of Cu2AgInS4 QDs/TiO2 NPs (3.92%) based QDSC.