▎ 摘　　要

Phonon scattering at the carbon nanotube-graphene interface is studied in the pillared graphene structure, using the phonon wave packet method. Qualitatively different scattering characteristics, compared to previous studies of carbon nanotube systems, are observed. The phonon group velocity, dictating the energy transmission in simple carbon nanotube systems, is found to play an insignificant role. Distributing the incoming phonon energy to both sides of the interface more or less equally, the graphene interface provides a strong diffusive scattering site, which features a microscopic understanding of the decisive role of junction on the thermal transport in the pillared graphene hierarchical structure. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4711206]