Time Transients with Inductive Loop Traces in Metal Halide Perovskites

Metal halide perovskites are archetypal ionic-electronic materials with great prospects for optoelectronic applications. Among the rich variety of physics exhibited by ionic-electronic conduction, here, those most relevant to optoelectronic devices in which ionic mechanisms introduce a kinetic delay in the electronic phenomena are analyzed. The attention is focused on the inductive loop features and a dynamical model is developed to describe the corresponding complex multiscale dynamics in the time domain under experimental conditions, finally explaining the fundamental structure of the current transient responses in halide perovskite semiconductors. Based on complex capacitive and inductive patterns extensively studied in impedance measurements, an adequate interpretation of time domain methods capable of monitoring charge-carrier dynamics is produced. Therefore, this methodology identifies the characteristic parameters of all types of transient dynamics in metal halide perovskites, providing a suitable connection of correlated techniques, including impedance and chronoamperometric experiments, toward a robust interpretation of the device response. The scope of the method is fairly general, since these counterintuitive transient effects are observable not only in metal halide perovskites, but also in multiple materials and processes, mainly in different research fields pertaining to electrochemistry and electronics. While transient techniques are abundantly used to monitor the charge-carrier dynamics in metal halide perovskites, the interpretation of data obtained is highly challenging due to the richness and complexity of the observed physical processes. This work provides insights into the current responses with multiple timescale dynamics, which enable an understanding of the inherent ionic-electronic transient processes in device operation.image