Abstract
Herein, the steady-state transport equation for photoelectrons and photoholes in CdS/CdTe heterojunction solar cell under bias-dependent photoluminescence is solved analytically using the Galerkin (GM) and Homotopy Perturbation (HPM) methods. The obtained expressions for excess electron and hole concentrations allow us to find analytical expression for the photoluminescence (PL) intensity. The results of PL intensity obtained from this expression are compared with the available experimental data, where transport quantities (mobility and lifetime for electron and holes) are used as adjustable parameters. The values of transport parameters are extracted from the fitting process. Deviations of our theoretical results (using the derived expression of PL intensity) from the experimental data do exist when the same parameters used in the calculations of others are employed as input in the fitting process. However, the fittings to the experimental data are improved when different values of adjustable parameters are used. The product of lifetimes for holes and electrons is found sensitive to the degradation of the semiconductor when subjected to light intensity for 28 days. However, the values of mobility for holes and electrons are found different from those obtained by others. The deviation of our results may be attributed to the several assumptions and approximations adopted in the analytical solution.