Charge-transfer dynamics and nonlocal dielectric permittivity tuned with metamaterial structures as solvent analogues
Charge-transfer dynamics and nonlocal dielectric permittivity tuned with metamaterial structures as solvent analogues
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DOI：
10.1038/nmat4907
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发表时间：
2017-07-01
期刊：
影响因子：
41.2
通讯作者：
Andre, Pascal
中科院分区：
文献类型：
--
作者：
Lee, Kwang Jin;Xiao, Yiming;Andre, Pascal
电荷转移（CT）是生物学、物理学和化学中普遍存在的基本机制。在这里，我们证明多层双曲超材料（HMM）衬底可以改变CT动力学。以三苯基：苝二亚胺二元超分子自组装为模型体系，我们揭示了HMM结构存在下更长的CT态，电荷分离和重组特征时间分别增加了2.4和1.7倍，即相对变化分别为140和73%。为了从驱动力的角度解释这些实验结果，我们成功地在马库斯理论中引入了像偶极子相互作用。本文所证明的非局部效应与金属-介电对的数量直接相关，可以在介电常数中形式化，并且可以作为局部溶剂极性效应的固体模拟。该模型和额外的PH3T:PC60BM结果显示了这种非局部现象的普遍性，并且基材工程可以产生广泛的动态剪裁机会。这项工作为设计人造衬底来控制光电和化学应用中感兴趣的CT动力学铺平了道路。
Charge transfer (CT) is a fundamental and ubiquitous mechanism in biology, physics and chemistry. Here, we evidence that CT dynamics can be altered by multi-layered hyperbolic metamaterial (HMM) substrates. Taking triphenylene: perylene diimide dyad supramolecular self-assemblies as a model system, we reveal longer-lived CT states in the presence of HMM structures, with both charge separation and recombination characteristic times increased by factors of 2.4 and 1.7-that is, relative variations of 140 and 73%, respectively. To rationalize these experimental results in terms of driving force, we successfully introduce image dipole interactions in Marcus theory. The non-local effect herein demonstrated is directly linked to the number of metal-dielectric pairs, can be formalized in the dielectric permittivity, and is presented as a solid analogue to local solvent polarity effects. This model and extra PH3T:PC60BM results show the generality of this non-local phenomenon and that a wide range of kinetic tailoring opportunities can arise from substrate engineering. This work paves the way toward the design of artificial substrates to control CT dynamics of interest for applications in optoelectronics and chemistry.