Liu Yuqing, Zhong Mianzeng, Downey Elisabeth Ffion, Chen Xiaoyao, Li Tao, Nørgaard Kasper, Wei Zhongming
State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences & Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100083, People's Republic of China. Sino-Danish College, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China. Nano-Science Center and Department of Chemistry, University of Copenhagen, Copenhagen DK-2100, Denmark.
Nanotechnology. 2020 Apr 17;31(16):164001. doi: 10.1088/1361-6528/ab6681. Epub 2019 Dec 31.
The ultimate goal of molecular electronics is to achieve practical applications. For approaching the target, we have successfully fabricated solid-state junctions based on oligo(phenylene ethynylene)s (OPEs) and cruciform OPEs with extended tetrathiafulvalene (TTF) (OPE3 and OPE3-TTF) self-assembled monolayers (SAMs) with a diamine anchoring group. SAMs were confined in micropores with gold substrates to ensure well-defined device surface areas. The transport properties were conducted on a double-junction layout, which the rGO films used for top contacts and interconnects between adjacent SAMs. The solid-state devices based on OPE3-TTF SAMs showed the expected higher conductance under ambient conditions because of the incorporation of a TTF moiety. The two devices displayed varying degrees of temperature dependence with decreasing temperature, which resulted from the cross-conjugated OPE3-TTF molecule exhibiting quantum interference while the linear-conjugated OPE3 molecule did not. This study shows the temperature dependence of the electrical properties of molecular devices based on cruciform OPEs, further enriching the research results of functional molecular devices.
分子电子学的最终目标是实现实际应用。为了接近这一目标，我们成功制备了基于亚苯基乙炔（OPEs）和带有扩展四硫富瓦烯（TTF）的十字形OPEs（OPE3和OPE3-TTF）的固态结，其具有二胺锚定基团的自组装单分子层（SAMs）。SAMs被限制在带有金基底的微孔中，以确保器件表面积明确。传输特性是在双结布局上进行的，其中rGO薄膜用于顶部接触以及相邻SAMs之间的互连。基于OPE3-TTF SAMs的固态器件在环境条件下由于引入了TTF部分而显示出预期的更高电导率。这两个器件随着温度降低表现出不同程度的温度依赖性，这是由于十字共轭的OPE3-TTF分子表现出量子干涉，而线性共轭的OPE3分子则没有。这项研究展示了基于十字形OPEs的分子器件电学性质的温度依赖性，进一步丰富了功能分子器件的研究成果。
