School of Advanced Materials, Peking University Shenzhen Graduate School , Shenzhen 518055, China.
Key Laboratory for the Physics and Chemistry of Nanodevices, Department of Electronics, Peking University , Beijing 100871, China.
ACS Appl Mater Interfaces. 2017 Mar 1;9(8):7305-7314. doi: 10.1021/acsami.6b13500. Epub 2017 Feb 14.
One of the most striking features of organic semiconductors compared with their corresponding inorganic counterparts is their molecular diversity. The major challenge in organic semiconductor material technology is creating molecular structural motifs to develop multifunctional materials in order to achieve the desired functionalities yet to optimize the specific device performance. Azo-compounds, because of their special photoresponsive property, have attracted extensive interest in photonic and optoelectronic applications; if incorporated wisely in the organic semiconductor groups, they can be innovatively utilized in advanced smart electronic applications, where thermal and photo modulation is applied to tune the electronic properties. On the basis of this aspiration, a novel azo-functionalized liquid crystal semiconductor material, (E)-1-(4-(anthracen-2-yl)phenyl)-2-(4-(decyloxy)phenyl)diazene (APDPD), is designed and synthesized for application in organic thin-film transistors (OTFTs). The UV-vis spectra of APDPD exhibit reversible photoisomerizaton upon photoexcitation, and the thin films of APDPD show a long-range orientational order based on its liquid crystal phase. The performance of OTFTs based on this material as well as the effects of thermal treatment and UV-irradiation on mobility are investigated. The molecular structure, stability of the material, and morphology of the thin films are characterized by thermal gravimetric analysis (TGA), polarizing optical microscopy (POM), (differential scanning calorimetry (DSC), UV-vis spectroscopy, atomic force microscopy (AFM), and scanning tunneling microscopy (STM). This study reveals that our new material has the potential to be applied in optical sensors, memories, logic circuits, and functional switches.
与相应的无机半导体相比，有机半导体最显著的特点之一是其分子多样性。在有机半导体材料技术中，主要的挑战是创造分子结构基元，以开发多功能材料，从而实现所需的功能，同时优化特定的器件性能。偶氮化合物由于其特殊的光响应特性，在光子学和光电应用中引起了广泛的兴趣；如果明智地将其纳入有机半导体基团中，可以在先进的智能电子应用中创新性地利用它们，其中热和光调制用于调整电子性能。基于这一愿望，设计并合成了一种新型的偶氮功能化液晶半导体材料（E）-1-（4-（蒽-2-基）苯基）-2-（4-（癸氧基）苯基）二氮烯（APDPD），用于有机薄膜晶体管（OTFT）。APDPD 的紫外可见光谱在光激发下表现出可逆的光异构化，并且 APDPD 的薄膜基于其液晶相表现出长程取向有序。研究了基于该材料的 OTFT 的性能以及热处理和紫外辐照对迁移率的影响。通过热重分析（TGA）、偏光显微镜（POM）、差示扫描量热法（DSC）、紫外可见光谱、原子力显微镜（AFM）和扫描隧道显微镜（STM）对材料的分子结构、稳定性和薄膜形貌进行了表征。这项研究表明，我们的新材料有可能应用于光学传感器、存储器、逻辑电路和功能开关。
