Study of Charge Transport and Carrier Dynamics in Solution-Grown MAPbBr3 Single-Crystals for Efficient Radiation Sensing

Solution-grown metal halide perovskites are promising semiconductor materials for the development of efficient radiation sensors. An integral focus for radiation sensing is the reduction of trap states and the enhancement of charge transport properties. To achieve this, understanding the transport mechanism and carrier dynamics is essential. We present systematic studies of the charge transport mechanism by performing temperature-dependent current–voltage measurements and further study the carrier recombination dynamics by performing transient photoluminescence. Carrier dynamics revealed the presence of trap levels in the crystal, which dominate carrier recombination and limit carrier lifetime. The dark current studied on an asymmetric vertical device consisting of planar gold and indium contacts exhibiting a slight rectification property and temperature dependency in a limited temperature range. This temperature dependence suggests that the current is controlled by thermally activated process. However, when the temperature was below 253 K, the dependency vanished, suggesting other conduction mechanisms. By correlating the structural, optical, and electronic properties, this study provides insights into the charge transport and recombination mechanisms in solution-grown MAPbBr 3 single crystals.