Effectiveness of spin coating quantum dots deposition process onto mesoporous titanium dioxide for photovoltaic application

The aim of this work was to present an effective method for deposition onto a conductive material covered by a thin film on a glass surface using the spin coating technique.The TiO 2 layer, consisting of 99% anatase particles (~20 nm diameter), was applied via screen printing to an estimated thickness of ~5 µm onto TCO-coated glass (NEC A7).QDs were deposited using spin coating with controlled parameters: time 90 s, rotational speed 4000 rpm, and acceleration A=100 rpm/s.Three types of colloidal QDs dispersed in toluene were utilized: ZnCuInS/ ZnS (max.em 530 nm ) ZnCuInS/ZnS and (max.em 700 nm), both at 1 g/ml concentration, applied in volumes of 250 µl and 500 µl; and CdS (max.em 460 nm) at 0.5 g/ml concentration, applied in volumes of 500 µl and 1000 µl.Selected samples underwent post-deposition annealing at 250 °C for 15 minutes.Surface morphology was characterized using Scanning Electron Microscopy (SEM) in the backscattered electron (BSE) detector configuration, while optical properties were assessed using double-beam spectrophotometer.In conclusion, the results confirm the effectiveness of the spin coating technique for QDs deposition onto TiO 2 layers, validating its potential to enhance optoelectronic performance through improved light absorption and charge separation dynamics crucial for QD-sensitized solar cell applications