Key Laboratory of Advanced Display Materials and Devices, Ministry of Industry and Information Technology, Institute of Optoelectronics & Nanomaterials, College of Material Science and Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
Key Laboratory of Advanced Display Materials and Devices, Ministry of Industry and Information Technology, Institute of Optoelectronics & Nanomaterials, College of Material Science and Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
J Colloid Interface Sci. 2019 Oct 15;554:619-626. doi: 10.1016/j.jcis.2019.07.044. Epub 2019 Jul 16.
Fully-inorganic halide perovskites (HPs) have realized respectable progress in multiple optoelectronic applications. However, Cl-based fully-inorganic HPs that are ideal for ultraviolet (UV) photodetection applications in high demand still remain rarely explored mainly due to the poor solution processability compared with other counterparts. Here we propose a facile solution method to fabricate CsPbCl with not only high crystallinity but also a two dimensional (2D) morphology for efficient UV photodetection. 2D Ruddlesden-Popper perovskites (RPPs) are firstly prepared as the intermediate phase, which habitually grow into microplates owing to an intrinsic 2D structure. Then Cs was introduced in the form of highly soluble cesium acetate to exchange with the organic cations in the RPPs to produce 2D CsPbCl with preserved morphology and micron scale size. By this chemical route, the poor solubility issue can be addressed. All the procedures are conducted at room temperature in open air. The perfect band gap, high crystallinity and 2D morphology promise superior UV light sensing capability, one of the best overall performances featuring high responsivity, fast response speed, low driving voltages and good stability is obtained. This work is believed to fill in the "Cl-gap" for this promising class of material.
全无机卤化物钙钛矿（HPs）在多种光电应用中取得了令人瞩目的进展。然而，由于与其他同类材料相比，其溶液加工性能较差，理想用于高需求紫外（UV）光探测应用的基于 Cl 的全无机 HPs 仍很少被探索。在这里，我们提出了一种简便的溶液法来制备 CsPbCl，其不仅具有高结晶度，而且具有二维（2D）形态，可实现高效的 UV 光探测。二维 Ruddlesden-Popper 钙钛矿（RPPs）首先被制备为中间相，由于其固有二维结构，它通常会生长成微板。然后以高可溶性醋酸铯的形式引入 Cs，以与 RPPs 中的有机阳离子交换，从而生成具有保留形态和微米级尺寸的 2D CsPbCl。通过这种化学途径，可以解决溶解度差的问题。所有的程序都是在室温下在开放的空气中进行的。完美的带隙、高结晶度和 2D 形态保证了优异的紫外光感应能力，获得了最佳的整体性能之一，包括高响应率、快速响应速度、低驱动电压和良好的稳定性。这项工作有望填补该类材料的“Cl 缺口”。
