Electron transport through self-assembled monolayers of tripeptides
E. Mervinetsky, I. Alshanski, S. Lenfant, D. Guerin, L. Medrano Sandonas, A. Dianat, R. Gutierrez, G. Cuniberti, M. Hurevich, S. Yitzchaik, D. Vuillaume
We report how the electron transport through a solid-state metal/Gly-Gly-His tripeptide (GGH) monolayer/metal junction and the metal/GGH work function are modified by the GGH complexation with Cu2+ ions. Conducting AFM is used to measure the current-voltage histograms. The work function is characterized by combining macroscopic Kelvin probe and Kelvin probe force microscopy at the nanoscale. We observe that the Cu2+ ions complexation with the GGH monolayer is highly dependent on the molecular surface density and results in opposite trends. In the case of a high density monolayer the conformational changes are hindered by the proximity of the neighboring peptides, hence forming an insulating layer in response to copper-complexation. Whereas the slightly lower density monolayers allow for the conformational change to a looped peptide wrapping the Cu-ion, which results in a more conductive monolayer. Copper-ion complexation to the high- and low-density monolayers systematically induces an increase of the work functions. Copper-ion complexation to the low-density monolayer induces an increase of electron transport efficiency, while the copper-ion complexation to the high-density monolayer results in a slight decrease of electron transport. Both of the observed trends are in agreement with first-principle calculations. Complexed copper to low density GGH-monolayer induces a new gap state slightly above the Au Fermi energy that is absent in the high density monolayer.
Benzo-bis(imidazole) self-assembled monolayers molecular junctions in meta or para conformation: effects of protonation on the electrical and thermal conductances
Centre Interdisciplinaire de Nanoscience de Marseille (CINaM), CNRS（马赛跨学科纳米科学中心）
A Universal Strategy of Perovskite Ink-Substrate Interaction to Overcome the Poor Wettability of a Self-Assembled Monolayer for Reproducible Perovskite Solar Cells
已经报道了采用自组装单层（诸如Me-4PACz）作为空穴传输层的Percent太阳能电池表现出高器件效率。然而，由于钙钛矿墨水与底层Me-4PACz的相互作用较差，导致Me-4PACz上的钙钛矿润湿性较差，这对制造高效的钙钛矿器件提出了重大挑战。采用由二甲基甲酰胺（DMF）、二甲基亚砜（DMSO）和N-甲基-2-吡咯烷酮（NMP）组成的三元共溶剂体系来改善钙钛矿油墨-基底相互作用并获得均匀的钙钛矿层。与DMF、DMSO基油墨相比，NMP的包含显示钙钛矿油墨与Me-4PACz的相当高的结合能，如通过密度泛函理论计算所揭示的。通过优化的三重共溶剂比，钙钛矿器件在0.16 cm 2、0.72 cm 2和1.08 cm 2的有源面积下分别提供> 20%、19.5%和~18.5%的高功率转换效率。重要的是，这种钙钛矿油墨-基底相互作用方法是通用的，并且有助于获得其他钙钛矿组合物如MAPbI 3、FAMAPbI 3-xBrx和无MA的FACsPbI 3-xBrx的均匀层和高光伏器件性能。
High temporal stability of niobium superconducting resonators by surface passivation with organophosphonate self-assembled monolayers
Technical University of Munich（慕尼黑工业大学）；Fraunhofer Institute for Electronic Microsystems and Solid-State Technologies（弗劳恩霍夫电子微系统和固态技术研究所）；Walther-Meißner-Institut, Bayerische Akademie der Wissenschaften（瓦尔特·迈斯纳研究所，巴伐利亚科学院）
Charge transport through redox active [H7P8W48O184]33- polyoxometalates self-assembled onto gold surfaces and gold nanodots
聚氧乙烯酸酯（POM）是一种具有氧化还原活性的分子氧化物，由于其可以集成到纳米器件中，如高密度数据存储器和非易失性存储器中，引起了人们越来越多的兴趣。在这项工作中，我们研究了带负电荷的[H7 P8 W 48 O 184]33- POM到带正电荷的8-氨基-1-辛硫醇自组装单分子膜（SAMs）上的静电沉积，该自组装单分子膜预先形成在金基底上或金纳米点阵列上。选择环状[H7 P8 W 48 O 184]33- POM作为具有高电荷存储容量的大POM的实例。为了避免在衬底上形成POM聚集体，这将引入局部电性能的变化，必须特别注意预先形成的SAM晶种层，其本身应该被剥夺聚集体。在必要时，冲洗步骤被发现是至关重要的，以消除这些聚集体，并提供均匀覆盖的基板，用于随后的POM沉积和电特性。这尤其适用于市售的金/玻璃基材，而这些冲洗步骤在粗糙度非常低的模板剥离金的情况下不是必需的。通过相关的分子结和纳米点分子结（NMJs）的电荷输运已被探测的导电原子力显微镜。我们分析了不同模型下的电流-电压曲线：电子隧穿自组装膜（Simmons模型）、跃迁电压谱（TVS）方法和分子单能级介导输运（Landauer方程），并讨论了分子结的能量学。我们的结论是能级对齐的烷基间隔和POM最低占据分子轨道（LUMO），可能是由于偶极效应。
