Sub-5 nm single crystalline organic p–n heterojunctions

Abstract

The cornerstones of emerging high-performance organic photovoltaic devices are bulk heterojunctions, which usually contain both structure disorders and bicontinuous interpenetrating grain boundaries with interfacial defects. This feature complicates fundamental understanding of their working mechanism. Highly-ordered crystalline organic p–n heterojunctions with well-defined interface and tailored layer thickness, are highly desirable to understand the nature of organic heterojunctions. However, direct growth of such a crystalline organic p–n heterojunction remains a huge challenge. In this work, we report a design rationale to fabricate monolayer molecular crystals based p–n heterojunctions. In an organic field-effect transistor configuration, we achieved a well-balanced ambipolar charge transport, comparable to single component monolayer molecular crystals devices, demonstrating the high-quality interface in the heterojunctions. In an organic solar cell device based on the p–n junction, we show the device exhibits gate-tunable open-circuit voltage up to 1.04 V, a record-high value in organic single crystalline photovoltaics.

Evolutionary 2D organic crystals for optoelectronic transistors and neuromorphic computing

“…Another advantage of reducing the thickness of organic crystals is that it boosts the efficiency of carrier injection and modulation from metal electrodes, which can aid in the discovery of the internal carrier transportation mechanism [64,65]. The use of low-resistance ohmic contact shorten device switching times while also lowers operational voltage and power consumption [66,67].…”

Development of receptor-modified organic transistor-based biosensing

“…值得注 意的是, 降低有机半导体薄膜可能会引入大量缺陷, 限 制了高迁移率和高稳定性晶体管传感器的发展. Jiang 课题组 [56,57] 构建了单分子层分子晶体(MMC)器件, 该 类晶体管的高电学性质保证了器件的信号放大功能, 在多种传感器中获得了广泛应用. 在MMC中引入微孔 结构不但可以维持高迁移率, 还可以促进了其在高选 择性和特异性传感研究中的应用 [58] .…”

The prospects of organic semiconductor single crystals for spintronic applications

“…Also, their definite structures are beneficial for gaining an in-depth understanding of the structure – property relationships and exploring spin-related physical phenomenon in comparison with ordinary polycrystalline OSCs. 22–24 The development of multifunctional electronic devices based on OSSCs in the electronic area is relatively mature, 22–24 covering devices such as organic light-emitting diodes (OLEDs), 67,68 organic light-emitting transistors (OLETs), 24,69 organic photovoltaic (OPV) devices, 24,70 and so forth. Taking information from the abundant theoretical systems relating to organic electronics, versatile spintronic devices based on organic thin films are emerging in an endless stream.…”

“…Recently, Xiao et al fabricated an ultra-thin vertical organic crystalline p–n heterojunction. 70 Such a heterojunction with a high-quality interface was applied in an OPV device, displaying an open-circuit voltage of up to 1.04 V. 70 This study offers new ideas for innovations relating to organic spin photovoltaic devices.…”