Enhancing the Efficiency of Organic Solar Cell By Incorporating Copper Nanoparticles in PEDOT:PSS

The performance of bulk heterojunction organic solar cell can be enhanced by incorporating plasmonic copper nanoparticles. In this study, a device with the architecture ITO/PEDOT:PSS:CuNPs/P3HT:PCBM/Ag was fabricated, where PEDOT:PSS was treated with copper nanoparticles synthesised by chemical reduction. Transmission electron microscopy revealed spherical copper nanoparticles with increasing average particle size as the concentration of copper sulphate increases. A face-centred cubic structure with (111), (200) and (220) phases for copper nanoparticles was confirmed using X-ray diffraction. The incorporation of copper nanoparticles induced the plasmonic resonance at 562 nm resulting in light scattering, which was not observed for pristine PEDOT:PSS. The copper nanoparticles are uniformly dispersed in PEDOT:PSS as displayed by scanning electron microscopy. The increase in concentration and annealing temperature of copper nanoparticles improved the intensity of Cα = Cβ vibration mode for PEDOT:PSS and P3HT:PCBM. Incorporating copper nanoparticles in PEDOT:PSS has improved the power conversion efficiency of ITO/PEDOT:PSS:CuNPs/P3HT:PCBM/Ag solar cell from 0.09 to 5.44% as a result of the induced plasmonic resonance observed in the ultraviolet-visible spectra.