Researchers at China's Shanghai University of Electric Power have used dibenzoylmethane (DBM) as a precursor additive introduced in order to regulate the crystallization of CsPbI2Br perovskite while passivating its associated defects.
Inorganic CsPbI2Br perovskite solar cells (PSCs) have attracted massive interest but the tendency towards unruly crystallization and poor film quality of inorganic CsPbI2Br perovskites are major factors limiting their performance improvement. In their recent work, the scientists used DBM additive engineering for efficient and stable carbon-based CsPbI2Br PSCs.
It was shown that DBM promotes the nucleation rate of CsPbI2Br and increases its crystallinity, promoting phase stability.
Additionally, DBM can passivate uncoordinated Pb2+ defects, thereby significantly reducing non-radiative recombination, and can also decrease the energy level difference between CsPbI2Br/Carbon.
As a result, when DBM additive is incorporated in the CsPbI2Br, the power conversion efficiency (PCE) of the device with the fluorine doped tin oxide glass (FTO)/SnO2/CsPbI2Br/Carbon structure is significantly improved to 13.46%, an significant increase compared to the control device (11.72 %).
The unpackaged devices exhibit excellent air and thermal stability, remaining over 90% of its initial PCE after aging for 500 h under ambient conditions, or continuous heating at 65 °C in glovebox for 500 h, respectively.
