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In this study, we aimed to increase the knowledge regarding the response mechanisms which were associated with the formation of CdS thin films. CdS thin film remains the most appealing alternative for many researchers, as it has been a capable buffer material for effect in film based polycrystalline solar cells (CdTe, CIGSe, CZTS). The Linker Assisted and Chemical Bath Deposition (LA-CBD) technique, which combines the Linker Assisted (LA) technique and the chemical bath deposition (CBD) method for forming high quality CdS thin film, was presented as an efficient and novel hybrid sensitization technique. CdS films were bound to soda lime with the help of electrostatic forces, which led to the formation of the intermediate complexes [Cd (NH3)4]2+ that helped in the collision of these complexes with a soda lime slide. Salvia dye and as a linker molecule 3-Mercaptopropionic acid (MPA) was used in the one step fabrication technique. Optical results showed that the bandgap varied in the range of (2.50 to 2.17) eV. Morphological properties showed a homogeneous distribution of the particles that aspherical in shape in the CdS + MPA + Salvia dye films. This technique significantly affected on the electrical characterizations of CdS films after the annealing process. The CdS + Ag + MPA + Salvia dye films showed the maximum carrier concentration and minimum resistivity, as 5.64 × 10 18 cm−3 and 0.83 Ω cm respectively.

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This study examined and described the optical and photovoltaic (PV) characterizations of the Fruit Areca catechu (pinang) as a new type of organic sensitizer. Recent reports stated that including chenodeoxycholic acid (CDCA) in the dye improves the performance of dye-sensitized solar cells (DSSCs). The effectiveness of PV dye was investigated by applying it in a DSSC. The absorption spectra indicated that natural dyes with CDCA has an excellent stabilizing ability. The Fourier-transform infrared spectra indicated the existence of carboxylic and hydroxyl functional groups in the naturally extracted dye. These functional groups were responsible for the rapid electron transfer and strong electronic linkages of interactions within the TiO2 surface. In this study, photoluminescence spectra analysis showed that by narrowing the bandgap, incorporating CDCA as a co-adsorbent in natural dye could generate a significant photocurrent. The overall power conversion efficiency was enhanced by 4.6%. Moreover, the cell efficiency reached up to 0.076% after adding 1.5 mM of CDCA without optimizing the sensitization time. Results demonstrated that the present study contributes toward the improvement of DSSC through efficient electron injection.

Quantum bandgap buffer layers can improve sunlight absorption in the short wavelength region, hence improving the performance of CIGS solar cells. In this study, we use numerical modelling to determine the impact of various buffer layers' electrical characteristics on the performance of CIGS thin film photovoltaic devices, particularly, carrier concentration and the quantum effect. As well Ag2S buffer layer has been experimentally examined to fulfilment its effect in term of bulk and quantum bandgap. Experimental results depicted that, Ag2S QDs has polycrystalline nature of films, with smooth surface roughness, and average diameter 4 nm. Meanwhile, a simulation revealed that the Fermi level of the (n-buffer layer) material shifts closer to the conduction band with an increase in carrier concentration. The findings indicate that, a buffer layer with a wider bandgap and carrier concentration is an essential demand for achieving a device with a higher conversion efficiency and a broader bandgap-CBO window. It was attributed to beneficial synergistic effects of high carrier concentration and narrower depletion region, which enable carriers to overcome high CBO barrier. Most importantly, modelling results indicate that the optic-electrical characteristics of the buffer layer are critical in determining the progress of a CIGS solar cell.