Crystal orientation and grain size: do they determine optoelectronic properties of MAPbI3 perovskite?

• DOI: 10.48550/arxiv.1907.07363
• Publication Date: 2019-01-01
• Authors: Loreta A. Muscarella; Eline M. Hutter; Sandy Sánchez; Christian D. Diel...; Tom J. Savenije; Anders Hagfeldt; Michael Saliba; Bruno Ehrler
• Keywords: Crystal (programming language)

It is thought that growing large, oriented grains of perovskite can lead to more efficient devices. We study MAPbI3 films fabricated via Flash Infrared Annealing (FIRA) consisting highly oriented, large grains. Domains observed in the SEM are often misidentified with crystallographic grains, but images don't provide diffraction information. measure grain size, crystal structure and orientation using Electron Back-Scattered Diffraction (EBSD) we how these affect optoelectronic properties as characterized by local photoluminescence (PL) time-resolved microwave conductivity measurements (TRMC). find a spherulitic growth yielding (tens micron), along (112) (400) planes contrast randomly smaller (400 nm) conventional antisolvent (AS) dripping. observe enhancement shift emission at different regions FIRA clusters, be explained combination light-outcoupling self-absorption. no effect on properties. Additionally, despite substantial difference size between our sample AS sample, similar charge carrier mobilities lifetime for two films. These findings show quality not necessarily related crystalline domains indicating fabrication requirements may relaxed perovskites.