Since the first solar cell was developed, to the present date the low efficiency of the energy conversion has been a matter of concern to the researchers. At, present, solar cells are made up of the p-n junction fabrication of the Si or the GaAs which, first, due to high bandgap makes it difficult for the electron emission and decreases the efficiency of the cell, second it cannot utilize the maximum part of the spectrum of the solar energy reaching the earth and hence, most of the energy gets wasted [1]. We have performed numerical studies on semiconducting compounds by using heterojunction methodology for photovoltaic applications to produce solar cells with economic and better performance. Poisson's equation and Anderson's rule has been used to perform the simulations of heterostructure band alignment in Solar Cell Capacitance Simulator (SCAPS 1D®). Band alignment graphs have been plotted for different heterointerface, and quantum efficiency graph has been plotted for the whole model of a solar cell, and the results were analysed.