Octahedral distortion driven by CsPbI<sub>3</sub> nanocrystal reaction temperature – the effects on phase stability and beyond
Anastasia Matuhina, G. Krishnamurthy Grandhi, Maning Liu, Jan‐Henrik Smått, Noolu Srinivasa Manikanta Viswanath, Harri Ali‐Löytty, Kimmo Lahtonen, Paola Vivo
Abstract
NCs, encompassing dispersions, films, and even devices by tuning the hot-injection temperature between 120-170 °C. Our findings suggest that the transition from the black to the yellow phase occurs after over a month for NCs synthesized at 150 °C (150@NCs). Structural refinement studies attribute the enhanced stability of 150@NCs to their observed lowest octahedral distortion. The 150@NCs also lead to stable unencapsulated solar cells with unchanged performance upon 26 days of shelf storage in dry air. Our study underlines the importance of scrutinizing synthesis parameters for designing stable perovskite NCs towards long-lasting optoelectronic devices.