A synergistic approach in designing InP/ZnS quantum dot based CIGS solar cell

This research work investigates the implementation of non-toxic InP/ZnS quantum dot (QDs) buffer layer in solar cell. Due to its nontoxic behaviour, it is a better replacement of commonly used CdS buffer layer. InP/ZnS quantum dots buffer layer enhances light absorption, leading to a broader spectral response and improved power conversion efficiency. Graded CIGS (CuIn1-xGaxSe2) is used as absorber layer in this study for better utilization of solar spectrum. The combined utilization of an InP/ZnS QD buffer layer and a graded absorber layer results in a synergistic enhancement of the cell's performance. Further optimization of CIGS layers is achieved by varying the gallium content (x) in the Cu(In1−xGax)Se2. For the gallium content (x) in the range of 0.20 to 0.15, maximum efficiency is achieved which is 31.20 %. Numerical modeling is employed in this study to analyze how variations in thickness, doping concentration, and defect density impact the solar cell performances.