Our official English website, www.x-mol.net, welcomes your
feedback! (Note: you will need to create a separate account there.)
Bias-Polarity-Dependent Direct and Inverted Marcus Charge Transport Affecting Rectification in a Redox-Active Molecular Junction
Advanced Science ( IF 14.3 ) Pub Date : 2021-06-19 , DOI: 10.1002/advs.202100055 Yingmei Han 1 , Cameron Nickle 2 , Maria Serena Maglione 3 , Senthil Kumar Karuppannan 1 , Javier Casado-Montenegro 3 , Dong-Chen Qi 4 , Xiaoping Chen 1 , Anton Tadich 5 , Bruce Cowie 5 , Marta Mas-Torrent 3 , Concepció Rovira 3 , Jérôme Cornil 6 , Jaume Veciana 3 , Enrique Del Barco 2 , Christian A Nijhuis 1, 7, 8
Advanced Science ( IF 14.3 ) Pub Date : 2021-06-19 , DOI: 10.1002/advs.202100055 Yingmei Han 1 , Cameron Nickle 2 , Maria Serena Maglione 3 , Senthil Kumar Karuppannan 1 , Javier Casado-Montenegro 3 , Dong-Chen Qi 4 , Xiaoping Chen 1 , Anton Tadich 5 , Bruce Cowie 5 , Marta Mas-Torrent 3 , Concepció Rovira 3 , Jérôme Cornil 6 , Jaume Veciana 3 , Enrique Del Barco 2 , Christian A Nijhuis 1, 7, 8
Affiliation
|
This paper describes the transition from the normal to inverted Marcus region in solid-state tunnel junctions consisting of self-assembled monolayers of benzotetrathiafulvalene (BTTF), and how this transition determines the performance of a molecular diode. Temperature-dependent normalized differential conductance analyses indicate the participation of the HOMO (highest occupied molecular orbital) at large negative bias, which follows typical thermally activated hopping behavior associated with the normal Marcus regime. In contrast, hopping involving the HOMO dominates the mechanism of charge transport at positive bias, yet it is nearly activationless indicating the junction operates in the inverted Marcus region. Thus, within the same junction it is possible to switch between Marcus and inverted Marcus regimes by changing the bias polarity. Consequently, the current only decreases with decreasing temperature at negative bias when hopping is “frozen out,” but not at positive bias resulting in a 30-fold increase in the molecular rectification efficiency. These results indicate that the charge transport in the inverted Marcus region is readily accessible in junctions with redox molecules in the weak coupling regime and control over different hopping regimes can be used to improve junction performance.
中文翻译：
偏置极性相关的直接和反马库斯电荷传输影响氧化还原活性分子结中的整流
本文描述了由苯并四硫富瓦烯 (BTTF) 自组装单层组成的固态隧道结中从正常区域到倒置 Marcus 区域的转变，以及这种转变如何决定分子二极管的性能。温度相关归一化微分电导分析表明 HOMO（最高占据分子轨道）在大负偏压下的参与，这遵循与正常 Marcus 机制相关的典型热激活跳跃行为。相比之下，涉及 HOMO 的跳跃在正偏压下主导电荷传输机制，但它几乎没有激活，表明结在反马库斯区域中运行。因此，在同一结内，可以通过改变偏置极性在 Marcus 和反转 Marcus 状态之间切换。因此，当跳跃被“冻结”时，电流仅在负偏压下随着温度降低而降低，但在正偏压下不会导致分子整流效率提高 30 倍。这些结果表明，在弱耦合状态下，在与氧化还原分子的连接中，反向马库斯区域中的电荷传输很容易获得，并且可以使用对不同跳跃状态的控制来提高连接性能。
更新日期：2021-07-21
中文翻译：
偏置极性相关的直接和反马库斯电荷传输影响氧化还原活性分子结中的整流
本文描述了由苯并四硫富瓦烯 (BTTF) 自组装单层组成的固态隧道结中从正常区域到倒置 Marcus 区域的转变，以及这种转变如何决定分子二极管的性能。温度相关归一化微分电导分析表明 HOMO（最高占据分子轨道）在大负偏压下的参与，这遵循与正常 Marcus 机制相关的典型热激活跳跃行为。相比之下，涉及 HOMO 的跳跃在正偏压下主导电荷传输机制，但它几乎没有激活，表明结在反马库斯区域中运行。因此，在同一结内，可以通过改变偏置极性在 Marcus 和反转 Marcus 状态之间切换。因此，当跳跃被“冻结”时，电流仅在负偏压下随着温度降低而降低，但在正偏压下不会导致分子整流效率提高 30 倍。这些结果表明，在弱耦合状态下，在与氧化还原分子的连接中，反向马库斯区域中的电荷传输很容易获得，并且可以使用对不同跳跃状态的控制来提高连接性能。
京公网安备 11010802027423号