Nonlinear current-voltage characteristics due to ion migration in low-dimensional organic metal halide hybrids

Perovskite-related metal halide hybrids are currently a hot topic in materials research because of their affordability, efficiency, and abundance. Rapid advances are being made in terms of improving the performance of perovskite-based photovoltaics, but the materials remain unstable in the presence of light, moisture, and heat. A more comprehensive understanding of the physical processes of these materials is necessary for us to make improvements to the stability and efficiency of organic metal halide hybrids. Specifically, much research in this field focuses on higher-dimensional (2D, 3D) structures. Lower-dimensional materials (1D and 0D) may provide more stability by virtue of their molecular structures, but require further investigation. One issue that is particularly relevant to stability is ion migration in these materials, in which mobile ions move as a result of an applied electrical bias and induce an electric field that opposes said bias. This research examines data taken from several lower-dimensional samples while they are exposed to a light source in order to gain a deeper understanding of the electrical transport properties of dimethylethylene diaminium tin iodide (C4N2H14SnI4). In particular, we will examine the effect that ion migration may have on the current-voltage characteristics of C4N2H14SnI4.