Wu Ziye, Cui Peng, Deng Mingsen
School of Information, Guizhou University of Finance and Economics, Guiyang 550025, China.
Guizhou Provincial Key Laboratory of Computational Nano-Material Science, Guizhou Education University, Guiyang 550018, China.
Molecules. 2023 Oct 18;28(20):7158. doi: 10.3390/molecules28207158.
The construction of multifunctional, single-molecule nanocircuits to achieve the miniaturization of active electronic devices is a challenging goal in molecular electronics. In this paper, we present an effective strategy for enhancing the multifunctionality and switching performance of diarylethene-based molecular devices, which exhibit photoswitchable rectification properties. Through a molecular engineering design, we systematically investigate a series of electron donor/acceptor-substituted diarylethene molecules to modulate the electronic properties and investigate the transport behaviors of the molecular junctions using the non-equilibrium Green's function combined with the density functional theory. Our results demonstrate that the asymmetric configuration, substituted by both the donor and acceptor on the diarylethene molecule, exhibits the highest switching ratio and rectification ratio. Importantly, this rectification function can be switched on/off through the photoisomerization of the diarylethene unit. These modulations in the transport properties of these molecular junctions with different substituents were obtained with molecule-projected self-consistent Hamiltonian and bias-dependent transmission spectra. Furthermore, the current-voltage characteristics of these molecular junctions can be explained by the molecular energy level structure, showing the significance of energy level regulation. These findings have practical implications for constructing high-performance, multifunctional molecular-integrated circuits.
构建多功能单分子纳米电路以实现有源电子器件的小型化是分子电子学中的一个具有挑战性的目标。在本文中，我们提出了一种有效策略，用于增强基于二芳基乙烯的分子器件的多功能性和开关性能，这类器件具有光开关整流特性。通过分子工程设计，我们系统地研究了一系列电子供体/受体取代的二芳基乙烯分子，以调节其电子性质，并使用非平衡格林函数结合密度泛函理论研究分子结的输运行为。我们的结果表明，二芳基乙烯分子上同时被供体和受体取代的不对称构型表现出最高的开关比和整流比。重要的是，这种整流功能可以通过二芳基乙烯单元的光异构化来开启/关闭。通过分子投影自洽哈密顿量和偏压依赖的传输光谱，获得了这些具有不同取代基的分子结输运性质的这些调制。此外，这些分子结的电流-电压特性可以用分子能级结构来解释，这表明了能级调控的重要性。这些发现对于构建高性能、多功能分子集成电路具有实际意义。
