High photoelectric conversion efficiency and stability of carbon-based perovskite solar cells based on sandwich-structured electronic layers

Abstract

The electron transport layer is one of the critical factors affecting the power conversion efficiency (PCE) and stability of perovskite solar cells (PSCs). For this, we designed a SnO2/TiO2 (mesoporous structure)/SnO2 sandwich-structured electron transport layer, which is more conducive to the extraction of electrons and can effectively improve the short-circuit current of the devices. The obtained champion void-free transport layer carbon electrode devices had a PCE of 15.12 %, a short-circuit current of 20.45 mA/cm2, an open-circuit voltage of 1.11 V, and a fill factor of 67 %. The PCE remained above 75.02 % of its initial efficiency after 720 h in ambient conditions with humidity at 30–40 %. This work provides a reference strategy for improving the efficiency of the carbon-based PSCs.