Harnessing wrinkling morphologies of graphene on soft substrates for mechanically programmable interfacial thermal conductance  

作　　者：Qingchang Liu Baoxing Xu 

机构地区：[1]Department of Mechanical and Aerospace Engineering,University of Virginia,Charlottesville,Virginia 22904,USA

出　　处：《Nano Research》2023年第7期9608-9617,共10页纳米研究（英文版）

基　　金：This work was supported by the Office of Naval Research Young Investigator Program(No.N00014-20-1-2611);This work in part used the Extreme Science and Engineering Discovery Environment(XSEDE)through allocation TGMCH210002;which was supported by the National Science Foundation(No.ACI-1548562).

摘　　要：Strain engineering has been leveraged to tune the thermal properties of materials by introducing stress and manipulating local atomic vibrations,which poses a detrimental threat to the mechanical integrity of materials and structures and limits the capability to regulate thermal transport.Here,we report that the interfacial thermal conductance of graphene on a soft substrate can be regulated by harnessing wrinkling and folding morphologies of graphene,which could be well controlled by managing the prestrain applied to the substrate.These obtained graphene structures are free of significant in-plane mechanical strain and only have infinitesimal distortion to the intrinsic thermal properties of graphene.The subsequent thermal transport studies with pumpprobe non-equilibrium molecular dynamics(MD)simulation show that the thermal conductance between graphene structures and the substrate is uniquely determined by the morphological features of graphene.The atomic density of interfacial interactions,energy dissipation,and temperature distribution are elucidated to understand the thermal transport across each graphene structure and substrate.We further demonstrate that the normalized thermal conductance decreases monotonically with the increase of the equivalent mechanical strain,showing the capability of mechanically programmable interfacial thermal conductance in a broad range of strains.Application demonstrations in search of on-demand thermal conductance are conducted by controlling the geometric morphologies of graphene.This study lays a foundation for regulating interfacial thermal conductance through mechanical loading-induced geometric deformation of materials on a soft substrate,potentially useful in the design of flexible and stretchable structures and devices with tunable thermal management performance.

关 键 词：interfacial thermal conductance wrinkled graphene PUMP-PROBE atomic interaction mechanical loading 

分 类 号：TB383[一般工业技术—材料科学与工程]