Cheng Han-Wen, Wang Shan, Porter Marc D, Zhong Chuan-Jian
School of Chemical and Environmental Engineering, Shanghai Institute of Technology Shanghai 201418 China
Department of Chemistry, State University of New York at Binghamton Binghamton New York 13902 USA
Chem Sci. 2021 Mar 10;12(17):6081-6090. doi: 10.1039/d0sc06955h.
Intermolecular interactions play a critical role in the binding strength of molecular assemblies on surfaces. The ability to harness them enables molecularly-tunable interfacial structures and properties. Herein we report the tuning of the intermolecular interactions in monolayer assemblies derived from organothiols of different structures for the creation of nanoelectrode arrays or ensembles with effective mass transport by a molecular-level perforation strategy. The homo- and hetero-intermolecular interactions can be fully controlled, which is demonstrated not only by thermodynamic analysis of the fractional coverage but also by surface infrared reflection absorption and X-ray photoelectron spectroscopic characterizations. This understanding enables controllable electrochemical perforation for the creation of ensembles or arrays of channels across the monolayer thickness with molecular and nanoscale dimensions. Redox reactions on the nanoelectrode array display molecular tunability with a radial diffusion characteristic in good agreement with theoretical simulation results. These findings have implications for designing membrane-type ion-gating, electrochemical sensing, and electrochemical energy storage devices with molecular level tunability.
分子间相互作用在表面分子组装体的结合强度中起着关键作用。利用这些相互作用的能力能够实现分子可调的界面结构和性质。在此，我们报告了通过分子水平穿孔策略，对源自不同结构有机硫醇的单层组装体中的分子间相互作用进行调控，以创建具有有效质量传输的纳米电极阵列或集合体。同分子间和异分子间相互作用均可得到完全控制，这不仅通过分数覆盖率的热力学分析得以证明，还通过表面红外反射吸收和X射线光电子能谱表征得到证实。这种认识使得可控电化学穿孔能够用于创建跨越单层厚度的具有分子和纳米尺度尺寸的通道集合体或阵列。纳米电极阵列上的氧化还原反应显示出分子可调性，具有径向扩散特性，与理论模拟结果高度吻合。这些发现对于设计具有分子水平可调性的膜型离子门控、电化学传感和电化学能量存储器件具有重要意义。
