Proceedings of International Conference on Hybrid and Organic Photovoltaics (HOPV19)
Publication date: 6th February 2020
Solution-processed thin films of lead halide perovskites show exceptional optoelectronic properties, making them interesting candidates for a range of applications such as solar cells and light-emitting diodes. The thickness and crystallite-size in these films is typically in the sub-micron range, resulting in an abundance of grain-boundaries. Here we will describe techniques for growing thin single-crystalline lead perovskite crystallites with edge lengths of several tens of microns and thicknesses of around 1 micron, starting from single-source 1D lead halide perovskite precursors. We report our recent work of fabricating active electro-optical modulators (AEOM) from these crystals using focused-ion beam milling. These AEOMs exhibit > 98% light transmission intensity modulation with an applied external voltage of 45 V. In the final section of this talk we will report our recent efforts of growing single-crystalline mixed-halide lead perovskite platelets and demonstrate the visualization of photoinduced phase segregation in these materials.1 Upon illumination we observe the formation of iodide-rich domains throughout the entire crystal, demonstrating that light-induced phase segregation also occurs efficiently in absence of grain boundaries. Narrowband fluorescence imaging and time-resolved spectroscopy provided new insight into the nature of phase segregated domains and the collective impact on optoelectronic properties.
The authors acknowledge financial support by the Australian Research Council through the ARC Centre of Excellence in Exciton Science