A Semitransparent Inorganic Perovskite Film for Overcoming Ultraviolet Light Instability of Organic Solar Cells and Achieving 14.03% Efficiency.

Chen, Weijie; Zhang, Jingwen; Xu, Guiying; Xue, Rongming; Li, Yaowen; Zhou, Yinhua; Hou, Jianhui; Li, Yongfang · Adv Mater · 2018

basic_science · Level V

Where this comes from

Abstract

Organic solar cells (OSCs) can be unstable under ultraviolet (UV) irradiation. To address this issue and enhance the power conversion efficiency (PCE), an inorganic-perovskite/organic four-terminal tandem solar cell (TSC) based on a semitransparent inorganic CsPbBr<sub>3</sub> perovskite solar cell (pero-SC) as the top cell and an OSC as bottom cell is constructed. The high-quality CsPbBr<sub>3</sub> photoactive layer of the planar pero-SC is prepared with a dual-source vacuum coevaporation method, using stoichiometric precursors of CsBr and PbBr<sub>2</sub> with a low evaporation rate. The resultant opaque planar pero-SC exhibits an ultrahigh open-circuit voltage of 1.44 V and the highest reported PCE of 7.78% for a CsPbBr<sub>3</sub> -based planar pero-SC. Importantly, the devices show no degradation after 120 h UV light illumination. The related semitransparent pero-SC can almost completely filter UV light and well maintain photovoltaic performance; it additionally shows an extremely high average visible transmittance. When it is used to construct a TSC, the top pero-SC acting as a UV filter can utilize UV light for photoelectric conversion, avoiding the instability problem of UV light on the bottom OSC that can meet the industrial standards of UV-light stability for solar cells, and leading to the highest reported PCE of 14.03% for the inorganic-perovskite/organic TSC.