Computational and performance studies of Ag2S-Bi2S3 quantum dot-sensitised solar cells

In this work, theoretical and experimental techniques were employed to analyze the feasibility of 'green' Ag- and Bi-based QDs as sensitisers in QDSSC. In the computational approach, the geometrical structures and optoelectronic properties of anatase-TiO2 (101) surface sensitised with Ag2S, Bi2S3 and Ag2S-Bi2S3 nanoclusters were investigated by means of density functional theory. In the experimental approach, the performances of the QDSSCs were validated. The properties of the QD-sensitised TiO2 electrode were characterised with FESEM, TEM, EDS, and UV-visible spectroscopy. It was observed that Ag2S-Bi2S3 QDSSC treated with post heat treatment exhibited better efficiency. UV-VIS spectroscopy result showed that the same sample had better absorption below the 570 nm wavelength. Efficiency obtained was at the low side due to charge recombination.