Abstract

Metal halide perovskite solar cells (PSCs) have advanced to the forefront of solution-processed photovoltaic techniques and made stunning progress in power conversion efficiency (PCE). Further improvements in device performances rely on perfecting the structure and morphology of perovskite films. However, undesirable defects such as pinholes and grain boundaries are often created in film preparations due to lack of knowledge of the precise reaction mechanism. Here, in situ grazing-incidence X-ray diffraction (GI-XRD) investigations are performed, facilitated by other techniques, on the formation of the widely adopted MAPbI3 (MA = methylammonium) perovskite films from their intermediate adduct (IA) phases. The influences of solvent vapor atmospheres on MAPbI3 films are also systematically investigated, where the dynamic conversion processes between different phases are visualized in real time. Further in situ GI-XRD and infrared spectroscopy measurements reveal that the IA phases contain both N,N-dimethylformamide and dimethyl sulfoxide (DMSO) as coordinating molecules. By tuning the DMSO concentration in perovskite precursors, the ideal perovskite film is formed and the best PCE is achieved for the planar MAPbI3 -based PSCs. These findings highlight the role of IA phases and the effect of solvent atmospheres on the quality of perovskite films, providing direct insights into their growth mechanism.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.