Theory of piezotronic and piezo-phototronic effects on high performance perovskite solar cells

Piezotronic and piezo-phototronic effects can effectively modulate the Schottky barrier height (SBH) of the metal-semiconductor contact and the built-in electric field. Most models focus on the built-in electric field of perovskite solar cells, and polarization-modulated SBH is missing. We investigated piezotronic and piezophototronic effects on the Schottky barrier and built-in electric field of perovskite solar cells. A model of the surface potential induced by polarization was developed. The analytical and numerical results are calculated for perovskite solar cells. We found that the piezo-phototronic effect can significantly increase the performance of perovskite solar cells by reducing the height of the Schottky barrier. This model not only provides a fundamental physical picture of the piezotronic and piezo-phototronic effect on perovskite solar cells, but also paves a new path to develop high-efficiency perovskite solar cells.