Organic field effect transistor composed by fullerene C60 and heterojunctions

We present a study of the complex electronic behavior of a fullerene (C₆₀) molecule attached to six leads (heterojunctions), which works as a three-dimension rectifier. In addition, we confirmed that the fullerene works not only as an electron donor, but also as barrier and transport channel to electrons through the molecule. Moreover, when the phenylpropanodinilla (PPP) lead is orthogonally subjected to bias voltage, the charge distribution and the current displays regions of saturation and resonance similar to semiconductor devices. In order to understand the electronic transport in the molecule, we applied non-equilibrium green function (NEGF) method and performed Fowler-Nordheim (FN) and Millikan-Lauritsen (ML) analyses. The ML curves proved to be sufficient to describe the FN characteristics. In this work, we report the theoretical design for electronic transport of a 3D device (6-terminal).     

Mediated Electron Transfer Across Supported Bilayer Lipid Membrane with TCNQ‐Based Organometallic Compounds

Supported bilayer lipid membrane (s‐BLM) containing one‐dimensional compound 1, TCNQ‐based (TCNQ=7,7,8,8‐tetracyanoquinodimethane) organometallic compound {(Cu₂(μ‐Cl)(μ‐dppm)₂)(μ₂‐TCNQ)}_∞, was prepared and characterized on the self‐assembled monolayer (SAM) of 1‐octadecylmercaptan (C₁₈H₃₇SH) deposited onto Au electrode. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) results showed that the compound 1, dotted inside s‐BLM, can act as mediator for electron transfer across the membrane. Two redox peaks and the charge‐transfer resistance of 400 kΩ were observed for compound 1 inside s‐BLM. The mechanism of the electron transfer across s‐BLM by TCNQ is by electron hopping while TCNQ‐based organometallic compound is by conducting. Further conclusion drawn from this finding is that the TCNQ‐based organometallic compound embedded inside s‐BLM exhibits excellent electron transfer ability than that of free TCNQ. This opens a new path for the development of s‐BLM sensor and/or biosensor by incorporation with TCNQ‐based organometallic compounds.     

硅衬底上聚丙烯酰胺/氧化锌纳米线薄膜蓝色发光二极管

采用高分子络合软模板法利用高分子络合和低温氧化烧结反应,在硅衬底上自组装生长出顶面平滑具有六角柱形结构的ZnO纳米线,并基于此聚丙烯酰胺/ZnO纳米线体系构筑了聚合物基ZnO纳米线发光二极管器件,在相对低的阈值电压下实现了常温常压下电场驱动的蓝色发射光,并且其发光颜色可由其应用的激励电压方便地调控.几乎垂直排列的ZnO纳米线/高分子薄膜在器件中被作为发射层.该方法使用聚合物作为LED器件的粘结剂和发光层的分散介质,稳定了硅衬底上埋置在聚合物薄膜中的ZnO纳米线准阵列并对ZnO纳米晶的表面起钝化作用,防止发光猝灭.结果表明,新技术是一种低成本制备ZnO基紫外/蓝色发光材料的工艺,并且减少了以往工艺中要求ZnO薄膜p型掺杂的麻烦.     

纳米材料的化学锂化与电活性

基于国内外最新研究进展及本课题组的研究工作, 综述了纳米材料的化学锂化与电活性研究进展. 首先介绍了钼氧化物、钒氧化物、硒化物等高容量纳米材料的制备和锂化过程的化学问题;然后介绍了单纳米线器件及纳米线锂离子电池的组装、化学锂化与电活性等的最新进展. 指出单纳米线(带、管等)器件组装、锂离子迁移原位检测、有序阵列或复杂结构设计构筑以及锂化机理、静电耦合、锂离子迁移与界面作用等相关性的研究将是更深入探索纳米材料化学锂化与电活性的关键问题, 对纳米锂离子电池材料研究领域的发展起到促进作用.     

Self-assembly of well-ordered and highly uniform nanoripples induced by focused ion beam

Well-ordered and highly uniform nanoripple structures on the surface of single crystal LaAlO₃ (1 0 0), SrTiO₃ (1 0 0) and Al₂O₃ (0 0 0 1) were formed via self-assembly (not by beam writing) by focused ion-beam bombardment. The morphology and topography of nanoripple structures were characterized using in-situ focused ion-beam/scanning electron microscope, as well as ex-situ atomic force microscopy. Under off-normal bombardment without sample rotation, the characteristic wavelength of nanoripples varying from 248 to 395 nm on the LaAlO₃ (1 0 0) surface can be obtained by changing ion fluence and incident angle. When all sputtering parameters except the ion fluence are constant, the wavelength of nanoripples is increased with the enhanced ion fluence. These results demonstrate the potential application of using ion sputtering method for fabricating the well-ordered and highly uniform nanoripples which can be used in nanodevices.     

纳米粒子的精准组装

纳米材料由于其独特的光、电、磁、力学等性质,成为了构建功能材料与器件的理想基元。实现纳米粒子的精确组装,是探究粒子之间的耦合聚集性质和制备宏观功能器件的基础。但是由于纳米粒子的小尺寸以及在溶液中运动的随机性与复杂性,精准控制纳米粒子组装体的形貌以及在空间中的相对位置仍存在巨大挑战。为了将纳米粒子组装成理想的有序结构,许多控制粒子组装的策略与方法得到发展。本文首先概述了纳米粒子自组装的控制方法与典型形貌,着重分析了影响粒子精准排布的因素与控制方法,并对纳米粒子及其组装体的光学性质与器件应用的最新研究进展进行了讨论,最后对目前纳米粒子精准组装所面临的挑战以及未来发展的方向进行了展望。     

New strategy towards the efficient solid phase synthesis of cyclopeptides

Synthetic cyclopeptides, and particularly those designed from VEGF structure, present considerable interest for the development of nanodevices devoted to tumor imaging or drug delivery. In order to obtain functionalizable cyclopeptides, we herein present a novel efficient way based on Fmoc-Lys-ODmab use, which was applied to the synthesis of c(PHGRIK) cyclopeptide.     

基于3d元素掺杂的石墨二炔分子传感材料性能调控

二维碳材料因其独特的性质成为凝聚态物理、纳米电子学、生物医药等领域的前沿研究热点。石墨二炔具有天然的半导体特性及独特的大孔网状结构,在纳米电子器件和生物传感方面比石墨烯更具优势。本文使用第一性原理计算研究了单层石墨二炔的纳米带电子输运性质和及石墨二炔对小分子的吸附。我们考虑用掺杂3d金属原子的方法来增强对分子的吸附力。选择在石墨二炔表面吸附能较大的钪(Sc)、钛(Ti)原子,确定石墨二炔表面Sc、Ti单原子在室温下的稳定性,研究了Sc、Ti掺杂石墨二炔用于分子检测的潜在可能。从能带、载流子浓度等方面全面探讨了Sc、Ti掺杂石墨二炔对甲醛分子(HCHO)的响应。又进一步研究了石墨二炔与氨基酸分子间相互作用,发现色散力在相互作用中占主导地位。研究了吸附氨基酸对石墨二炔电子输运的影响,探讨石墨二炔在生物传感方面的潜在应用。     

Construction and Application of DNAzyme-based Nanodevices

The development of stimuli-responsive nanodevices with high efficiency and specificity is very important in biosensing, drug delivery, and so on. DNAzymes are a class of DNA molecules with the specific catalytic activity. Owing to their unique catalytic activity and easy design and synthesis, the construction and application of DNAzymes-based nanodevices have attracted much attention in recent years. In this review, the classification and properties of DNAzyme are first introduced. The construction of several common kinds of DNAzyme-based nanodevices, such as DNA motors, signal amplifiers, and logic gates, is then systematically summarized. We also introduce the application of DNAzyme-based nanodevices in sensing and therapeutic fields. In addition, current limitations and future directions are discussed.