Greatly enhanced photovoltaic performance of crystalline silicon solar cells via metal oxide

Abstract

Band-gap alignment engineering has now been extensively studied due to its high potential for application. Here we demonstrate a simple route to synthesize two metal oxide layers and align them together according to their bandgaps on the surface of crystalline silicon (c-Si) solar cells. The metal oxide layers not only extend absorption spectrum to generate extra carriers but also more efficiently separate electron–hole pairs. As a consequence, the photovoltaic performance of SnO2/CdO/Si double-layer solar cell (DLSC) is highly improved compared to the controlled Si solar cell, CdO/Si and SnO2/Si single-layer solar cells (SLSCs). Via alignment engineering, the SnO2/CdO/Si DLSC produces a short circuit photocurrent (Jsc) of 38.20 mA/cm2, an open circuit photovoltage (Voc) of 0.575 V and a fill factor (FF) of 68.7%, a conversion efficiency (η) of 15.09% under AM1.5 illumination.