Nanoparticle size effect on optical and electrical properties of P3HT: ICxA photoactive layer

Abstract This study investigates the relationship between the sizes of P3HT: ICxA nanoparticles (NPs) and the performance of organic photovoltaic (OPV) devices. Four samples (S1-S4), were prepared with different sodium dodecyl sulphate (SDS) concentrations, created varied NP sizes, ranging from 63.087 to 24.161 nm. Optical modeling technique findings confirmed that the highest current density of the active layer can be generated by the NPs ink (S1, 63.087 nm average, 10.758 mA cm −2 ) compared to smaller NPs (S4, 24.161 nm average, 9.387 mA cm −2 ). Electrical measurements confirmed that the S1 exhibited the highest dark current (4.770 μA), conductivity (0.530 ×10 −4 S cm −1 ), and lowest resistivity (18.868 kΩ.cm), with a 44% improvement at illumination conditions. The current measurements under dark conditions differed by ~50% between S1 and S4. Thermal treatments improved all samples by ~50% in comparison with RT conditions. This report’s findings revealed that the optimum performance of P3HT: ICxA NPs was achieved when the SDS concentration was 20–30 mg SDS or at NPs size 63.087–38.434 nm NPs.