Study of the Optical Characteristics of Materials for the Construction of Organic/Inorganic Solar Cells Using UV -VIS Spectroscopy

This study focuses on the UV-vis spectroscopic analysis of the active materials used to construct organic/inorganic solar cells. The analysis was carried out on PCMB: P3HT blend using toluene as the solvent. It was also carried out on different concentrations of ZnO solution. The absorption spectra show that the PCMB-P3HT blend exhibited the highest absorption between 584.55 and 623.33 nm. The transmittance spectra show no transmission within the wavelength in which the absorption is at its peak. The highest peak is obtained at 617.81 nm in both the absorption and extinction coefficients. The blended material has a direct band gap value of the PCMB: P3HT blend is 1.94 eV. The Absorption spectra of 0.4ml-ZnO, 0.8ml-ZnO, and 1.2 ml-ZnO show that 0.8ml-ZnO exhibited different absorption and better absorbance than that of 0.4ml-ZnO and 1.2 ml-ZnO, which have similar absorption spectra with each other. But they all exhibited maximum absorption at almost the same wavelength, at about 343– 346nm. The optical band gap for 0.4ml ZnO was discovered to be 3.1 eV. While that of 0.8ml and 1.2ml ZnO are 3.0eV and 2.3eV respectively. These values indicated that as the concentration increases, there is an increase in the band gap.