In principle, all semiconductor materials have photovoltaic
effect, which can be used for solar cells. So in theory, all of the
semiconductor materials should be solar photovoltaic materials,
photoelectric material has all physical appearance of
semiconductor materials. There are three reasons. Firstly, limit
of physical appearance of semiconductor materials makes
theoretical conversion efficiency of solar cells produced by
some materials low, which don’t have development and
application value. Secondly, the purification and the
preparation of materials are difficult, all semiconductor
materials don’t satisfy the high purity which should be needed
by produced solar cells in the present technical conditions