Double perovskites for X-ray imaging: a micro-spectroscopic study

After seminal reports of the interesting physical properties of metal halide perovskites (MHPs) in 2009 and 2012, the scientific interest into MHPs as light absorbers for next-generation solar cells has exploded. The excitement around MHPs stems from the combination of high absorption coefficients at visible and near-IR wavelengths, long carrier diffusion lengths, small exciton binding energies, and its simple solution-based processing. Justifiably, an early surge of research activity was inspired by an empirical race to enhance the photo-conversion efficiencies of photovoltaic devices. Early research however saw perovskite engineering significantly outpace the understanding of their physical properties. In response, the focus of researchers is steadily shifting toward the intrinsic properties of MHPs, as these will define their performance in applications which now also comprise various light detectors (e.g. X-ray detectors). My PhD project aims at unravelling physical properties of microcrystals and mm-size single crystals of double perovskites, trying to shed light on their potential use as active medium for X-ray detection. This is done by addressing three overarching goals: 1) development of new microscopy and spectroscopy modalities to unravel perovskite fundamental physics, 2) measurements on selected double perovskites and 3) testing the most performing materials as X-ray detectors.