Abstract
This article examines three generations of solar cells. On the basis of the proposed model, the anisotropy of the thickness of the surface layer and the surface energy of single-crystal silicon, amorphous silicon, crystalline films of cadmium telluride, copper-indium diselenide, gallium arsenide, indium phosphide, and lead-halide perovskite are calculated. Some of the elements represented a cubic structure, and some - a tetragonal structure. The thickness of the surface layer is a nanostructure, which is determined by one fundamental parameter - the atomic volume of the compound. It is shown that solar cells for cubic crystals should be selected with the (100) face, where the smallest thickness of the surface layer is observed, and for tetragonal crystals with the a but not c face. A small amount of surface energy corresponds to solar cells with a high conversion efficiency of sunlight.