A General Vapor-Induced Coating Approach for Layer-controlled Organic Single Crystals
A General Vapor-Induced Coating Approach for Layer-controlled Organic Single Crystals
复制标题
DOI：
10.1002/adfm.202212158
复制
发表时间：
2023-01-11
影响因子：
19
通讯作者：
Song, Yanlin
中科院分区：
文献类型：
--
作者：
Chen, Shengnan;Liu, Zhaoxin;Song, Yanlin
二维有机半导体晶体（2D OSC）由于其独特的材料优点，对于高性能电子和光电子器件至关重要。然而，由于溶液加工制备中分子沉积的无序性和质量传输的不可控性，制备具有可控分子层的高质量和大规模的2D OSC仍然具有挑战性。在这里，蒸汽诱导的弯月面调制策略，用于制备单向和稳定的Marangoni流，以引导非接触弯月面演变的报告，这确保了均匀的质量传输和有序的分子沉积，以实现高品质的二维OSC。表面张力差和基底润湿性对弯月面的形成至关重要，从而导致不同的弯月面变形状态和薄膜形貌。基于优化的蒸汽-溶剂体系，可控地制备了具有精确层定义的C-8-BTBT的二维OSCs。液膜高度和溶质浓度的差异在控制从单层到几层的分子尺度厚度方面是决定性的。此外，层依赖的电子和光电性能的薄膜进行了系统的研究。值得注意的是，高性能的偏振敏感的日盲光电探测器实现了光电流的二向色比高达2.26，相应的偏振图像传感器表现出上级日盲偏振成像能力，由于高结晶质量。
2D organic semiconductor crystals (2D OSCs) are vital for high-performance electronic and optoelectronic devices owing to their unique material merits. However, it is still challenging to fabricate high-quality and large-scale ultrathin 2D OSCs with controllable molecular layers due to the disordered molecular deposition and uncontrollable mass transport in solution-processing fabrication. Here, a vapor-induced meniscus modulating strategy for preparing unidirectional and stable Marangoni flow to guide contactless meniscus evolution is reported, which ensures uniform mass transport and ordered molecular deposition to achieve high-quality ultrathin 2D OSCs. Both the surface tension difference and the substrate wettability are critical to meniscus formation, which results in various meniscus deformation states and film morphologies. Based on the optimized vapor-solvent system, ultrathin 2D OSCs of C-8-BTBT with precise layer definition are prepared controllably. The discrepancies in liquid film height and solute concentration are decisive in controlling the molecular scale thickness ranging from mono to a few layers. Moreover, the layer-dependent electronic and optoelectronic properties of the ultrathin films are systematically investigated. Notably, high-performance polarization-sensitive solar-blind photodetectors are achieved with a dichroic ratio of photocurrent up to 2.26, and the corresponding polarimetric image sensor exhibits superior solar-blind polarization imaging capability thanks to the high crystalline quality.