Performance Enhancement of Organic Solar Cells via Modification of the PAni-TiO2 Interface with Hydrogen Plasma Treatment

Abstract

Severe research efforts are still underway to improve the performance of polyaniline (PAni)-based photoactive layers, which are one of the cheapest materials used in the production of organic solar cells. Polymer solar cells were created using an ITO/(PAni-TiO₂)/Au system. To improve the efficiency of the synthesised solar cells, the photoactive layers (PAni-TiO₂) were treated with a hydrogen-plasma discharge for short periods of time (0, 3, and 5 minutes). The morphology, microstructure, and optical properties of prepared samples and plasma-treated nanocomposite layers were studied and discussed. Before and after plasma treatment, the performance of bulk heterojunction (BHJ) cell samples was extensively examined. After the PAni-TiO₂ photoactive films have been treated, the absorption and optical band gap energy has increased. After 5 minutes of hydrogen plasma processing, the efficiency increased to 0.7 percent, compared to 0.36 percent for the pristine cell. The improvement in efficiency is attributed to a structural alteration that was accompanied by a rapid increase in surface roughness, which resulted in a reduction in reflected photons and, as a result, a rise in generated charge carriers.