Proceedings of Online Meetup - Beyond Lead Halide Perovskites: Syntheses and Applications of Metal Halide Semiconductors (MABP)
Publication date: 23rd April 2020
Polycrystalline films of metal halide perovskites present outstanding properties with huge potential in different contexts such as solid state illumination (LEDs), photovoltaics or nonlinear optical properties, among others. However, much about the working principles of these materials is not fully understood so far. This includes basic aspects such as the correlation of the photophysics with the structure, defects and morphology of the film itself and also with the present interfaces and layers in contact with them and even with the substrate characteristics. The lability of the compounds facilitates the synthesis at low temperatures but also confer low environmental stability which strongly limit their practical use in photovoltaics. Further, final properties are very dependent not only of the perovskite active layer but on the nature and properties of interfaces in the full device. Using strategies such as doping with ions or combining with graphene or organic molecules, we study the degradation and structure-properties correlations as well as on the stabilization and induced novel properties. We doped either the active layer or transport interlayer. By XRD, optical spectroscopy, and PV and IS characterizations of the device we observed that even small modifications has strong effect in final properties. Here, we show how a small concentration of graphene platelets into the PEDOT:PSS HTL layer in MAPbI3 inverted solar cells improve environmental stability and photovoltaic performance. Or acting directly on the MAPbI3 active layer, doping with small molecules, transport properties can be improved, resulting in an increase in Voc.
Funding by Projects RTI2018-096918-B-C41, AYUDA PUENTE 2019 URJC and ENE2017-90565-REDT National Excellence Network. Young Researchers R&D Project PAS2D (ref. F660). T. S. R. and C. R.-O. acknowledge the CM and European Social Fund by the Talento fellowship 2017-T2/IND-5586 and by PEJD-2018-PRE/IND-8839 Youth Employment Initiative (YEI).