Polarization‐Dependent Photoluminescence of a Highly (100)‐Oriented Perovskite Film

Abstract

Lead halide perovskite is one of the attractive functional materials owing to its outstanding opto-electronic properties, which have been addressed in numerous studies. This study aims to clarify the link between the growth pattern and the charge carrier related properties for the highly oriented perovskite film along the [100] direction. For this purpose, a CH 3 NH 3 PbI 3 thin film mainly grown along the [100] direction was fabricated and subjected to spectroscopic analysis to understand the basic optoelectronic features of the oriented film. A perovskite film with random growth was also fabricated for comparison. In particular, results from excitation polarization photoluminescence spectroscopy (ExPPS) revealed that the orientation of transition dipole moment, which is relevant to the anisotropic property of the film, is attributed to the growth direction of the perovskite film. This study suggests that the absorption anisotropy can affect the anisotropy in properties of the perovskite device. Furthermore, photodetectors with the perovskite films were fabricated to investigate the effect of growth direction on the photodetector performances, revealing that a photodetector with the oriented perovskite film showed larger photoresponses. In order to provide an explanation for such result, we performed a PL lifetime imaging study of the oriented and randomly grown perovskite films.[a] S.

Defect‐Dependent Crystal Plane Control on Inorganic CsPbBr3 Film by Selectively Anchoring (Pseudo‐) Halide Anions for 1.650 V Voltage Perovskite Solar Cells

“…In general, high‐quality perovskite monocrystalline or polycrystalline films with monolayered grains are desired to minimize the grain boundaries and defect densities — or rather, exposed crystal planes; [ 19,20 ] that is, defective crystal planes basically determine the overall charge trapping centers in perovskite films. The similar phenomena have been empirically reported, such as the anisotropic electronic properties of orientated film, [ 21 ] and that carrier lifetime, open‐circuit voltage ( V oc ) loss, and hysteresis highly correlate with the {111} and {110} twin domains, [ 22,23 ] demonstrating the non‐negligible effect of in‐plane feature on optoelectronic performances. In this fashion, the precise control on preferable crystal plane growth is expected to maximize charge transfer and power output.…”

Polarization‐Sensitive Halide Perovskites for Polarized Luminescence and Detection: Recent Advances and Perspectives

“…Until 2016, the linear polarization luminescence properties of HPs were systematically investigated, [23,24] and linearly polarized light detection based on HPs NWs was realized for the first time in this year. [25] Subsequently, linearly polarized luminescence based on HPs NCs, [26] NWs, [27,28] NPLs, [29,30] NRs, [31] composites, [32][33][34][35][36][37][38] and highly oriented film [39] were sequentially reported. Meanwhile, linearly polarized light detection was also being implemented in HPs-based single crystals, [40] NWs, [4,41,42] and NPLs.…”

“…[63] As a result, the thermally induced rotation of MA ions at high temperature, which results in the formation of ferroelectric domains in different directions, could be the sources of depolarization of PL emission at room temperature. Yun et al [39] also realized polarization-dependent PL of [100]oriented MAPbI 3 film by using thiophene-1-oxide (THTO) as additive. The MAPbI 3 film grown along the [100] direction could significantly enhance the TDM alignment of the film, resulting in polarization related to the growth direction.…”

“…Yun et al. [ 39 ] also realized polarization‐dependent PL of [100]‐oriented MAPbI 3 film by using thiophene‐1‐oxide (THTO) as additive. The MAPbI 3 film grown along the [100] direction could significantly enhance the TDM alignment of the film, resulting in polarization related to the growth direction.…”

“…This result is in consistent with the reported photodetector based on [100]‐oriented MAPbI 3 film. [ 39 ] It was found that the significantly enhanced TDM alignment in [100]‐oriented MAPbI 3 enabled the photodetector device with more effective charge extraction and longer carrier life, which is conducive to the performance improvement of the photodetector.…”