• 文献标题:   Hidden by graphene - Towards effective screening of interface van der Waals interactions via monolayer coating
  • 文献类型:   Article
  • 作  者:   AMBROSETTI A, SILVESTRELLI PL
  • 作者关键词:  
  • 出版物名称:   CARBON
  • ISSN:   0008-6223 EI 1873-3891
  • 通讯作者地址:   Univ Padua
  • 被引频次:   9
  • DOI:   10.1016/j.carbon.2018.07.011
  • 出版年:   2018

▎ 摘  要

Recent atomic force microscopy (AFM) experiments [ACS Nano 2014, 8, 12410-12417] conducted on graphene-coated SiO2 demonstrated that monolayer graphene (G) can effectively screen dispersion van der Waals (vdW) interactions deriving from the underlying substrate: despite the single-atom thickness of G, the AFM tip was almost insensitive to SiO2, and the tip-substrate attraction was essentially determined only by G. This G vdW opacity has far reaching implications, encompassing stabilization of multilayer heterostructures, micromechanical phenomena or even heterogeneous catalysis. Yet, detailed experimental control and high-end applications of this phenomenon await sound physical understanding of the underlying physical mechanism. By quantum many-body analysis and ab-initio Density Functional Theory, here we address this challenge providing theoretical rationalization of the observed G vdW opacity for weakly interacting substrates. The non-local density response and ultra slow decay of the G vdW interaction ensure compensation between standard attractive terms and many-body repulsive contributions, enabling vdW opacity over a broad range of adsorption distances. vdW opacity appears most efficient in the low frequency limit and extends beyond London dispersion including electrostatic Debye forces. By virtue of combined theoretical/experimental validation, G hence emerges as a promising ultrathin shield for modulation and switching of vdW interactions at interfaces and complex nanoscale devices. (C) 2018 Elsevier Ltd. All rights reserved.