An inorganic hole-transport material of CuInSe2 for stable and efficient perovskite solar cells

In this work, we synthesized CuInSe 2 quantum dots (CISe QDs) and applied them to perovskite solar cells (PSCs) as an inorganic hole-transporting material (HTM). A power conversion efficiency (PCE) of 12.8% was achieved for the PSCs using CISe QDs as the HTM, which is the highest value reported to date for devices with a Cu-based chalcopyrite semiconductor as HTM. More importantly, the stability of PSCs with CISe QDs was significantly improved compared with that of the devices using spiro-OMeTAD as the HTM. These results demonstrate that CISe QDs are a promising inorganic HTM for PSCs with long-term stability and low cost.