| Thermal transport performance at the nanoscale and/or of biomaterials is essential to the success of many new technologies including nanoelectronics, biomedical devices, and various nanocomposites. Due to complicated microstructures and chemical bonding, thermal transport process in these materials has not been well understood yet. In terms of chemical bonding, it is well known that the strength of atomic bonding can significantly affect thermal transport across materials or across interfaces between materials. Given the intrinsic high strength of hydrogen bonds, this dissertation explores the role of hydrogen bonds in nanoscale thermal transport in various materials, and investigates novel material designs incorporating hydrogen bonds for drastically enhanced thermal conduction. Molecular dynamics simulation is employed to study thermal transport processes in three representative hydrogen-bonded materials: (1) crystalline motifs of the spider silk, silkworm silk and synthetic silk, (2) crystalline polymer nanofibers, and (3) polymer nanocomposites incorporating graphene or functionalized graphene. Computational and theoretical investigations demonstrate that hydrogen bonds significantly facilitate thermal transport in all three material systems. The underlying molecular mechanisms are systematically investigated. The results will not only contribute new physical insights, but also provide novel concepts of materials design to improve thermal properties towards a wide range of applications. |
