(417e) Identification of Thermal Barrier Areas in Membranes Assembled with 2D Materials By Using Scanning Thermal Microscopy

The thermal properties of 2D materials are of great interest for both fundamental research and applications. For heat conduction investigation in 2D materials, most of the researches are focusing on theoretical or simulation level while less work on practical application level was presented. In our work, scanning thermal microscopy (SThM) was employed as the characterization tool to analyze the influence of graphene oxide (GO) membrane surface geometry on its practical heat conduction properties. Experimental results revealed that the wrinkled structure was the area to prevent efficient heat flow. To reduce wrinkle effect and increase thermal conductivity, another 2D material-amino modified boron nitride (a-BN) was employed as a laminar crosslinker to provide edge-edge covalent bonding and facilitate the formation of a tightly packed GO/a-BN/GO hybrid structure. With a lower loading percent of BN in the GO/BN hybrid membranes, heat loss at the winkle part was reduced with an increased overall thermal conductivity value. Further increased loading of BN would generate an anabatic wrinkle effect which will prejudice heat conduction, leading to a decreased overall thermal conductivity value. This study not only provided a basic understanding of structure-thermal conduction property relationship in practical 2D membranes, but also proposed an effective method to improve heat transport through assembling with 2D sheet materials.