Intrinsic ion migration dynamics in a one-dimensional organic metal halide hybrid

TL;DR

This study uncovers the intrinsic ion migration behavior in a stable one-dimensional organic metal halide hybrid, providing insights into device hysteresis and stability issues in metal halide perovskites.

Contribution

It presents the first direct measurement and analysis of ion migration dynamics in a 1D organic metal halide hybrid, revealing a single exponential ion migration process.

Findings

Distinct intrinsic ion migration dynamic identified

Real-time ionic current measurements verified ion behavior

Insights into hysteresis mechanisms in metal halide devices

Abstract

Metal halide perovskites possess many physical properties amenable to optoelectronic applications, whereas the realization of these potentials has been hampered by their environmental and electronic instabilities. The morphological and molecular low dimensional perovskites and perovskite related materials have shown much promise in enhancing the chemical stability due to their unique molecular structures. Here we report on robust and reproducible four-terminal (4T) electrical measurements in a one-dimensional (1D) organic metal halide hybrid, (R)-{\alpha}-methylbenzylammonium lead triiodide ((R-{\alpha}-MBA)PbI3) made possible by its chemical stability. The results reveal a distinct intrinsic ion migration dynamic of single exponential, which underlies the unique 4T I-V characteristics. The dynamic is directly verified by real-time measurements of the transient ionic current. Our observations are consistent with photo-activation and field-assisted ion migration. The elucidated intrinsic ion dynamics may provide the physical basis for understanding and modelling the ubiquitous hysteresis in metal halides based electronic devices and new insights into the dynamics of ion migration in metal halide perovskites and hybrids in general.