Selective UV Absorbance of Copper Chalcogenide Nanoparticles for Enhanced Illumination Durability in Perovskite Photovoltaics

Abstract

The inherent optical and electrical properties of inorganic nanoparticles (NPs) give them high potential applicability in advanced energy devices. In this study, poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) was remodeled with aqueous synthesized copper-based chalcogenide NPs, and the novel properties were demonstrated. Raman spectra were used to analyze the changes in intrinsic binding of PEDOT:PSS and derive the main peak shift. X-ray diffraction spectral analysis showed that a photoactive layer stably formed on PEDOT:PSS with or without NPs. Perovskite photovoltaics (PPVs) were fabricated with the remodeled PEDOT:PSS as the hole transport layer, and the electrical properties were evaluated. The charge dynamincs factor and power conversion efficiency were higher in the NP-based PPVs than in the reference PEDOT:PSS devices. The charge behavior in the NP-based PPVs was investigated, and the following were identified: (1) improved device drive characteristics with photocurrent vs internal voltage, (2) a 10-fold increase in the hole mobility of the hole-only devices, (3) optimized efficiency in the photogenerated exciton dissociation test, and (4) improved charge transport resistance based on the impedance spectrum. The inherent optical properties of the NPs were examined in an illumination durability test of the perovskite material without encapsulation. Under continuous light exposure, PPV in NP-based devices showed better electrical stability than in the reference devices. Field-effect scanning electron microscopy analysis indicated that perovskite particles in the NP-based samples have advanced morphological stability compared to the reference samples. Thus, integrating NPs is an efficient strategy for fabricating advanced PPVs with improved device efficiency and illumination durability in a more cost-effective and eco-friendly manner.