Stitching Graphene Sheets with Graphitic Carbon Nitride: Constructing a Highly Thermally Conductive rGO/g-C<sub>3</sub>N<sub>4</sub> Film with Excellent Heating Capability
Yanyan Wang, Xian Zhang, Xin Ding, Ya Li, Bin Wu, Ping Zhang, Xiaoliang Zeng, Qian Zhang, Yuhang Du, Yi Gong, Kang Zheng, Xingyou Tian
Abstract
Driven by the evolution of electronic packaging technology for high-dense integration of high-power, high-frequency, and multi-function devices in modern electronics, thermal management materials have become a crucial component for guaranteeing the stable and reliable operation of devices. Because of its admirable in-plane thermal conductivity, graphene is considered as a desired thermal conductor. However, the promise of graphene films has been greatly weakened as the existence of grain boundaries lead to a high extent of phonon scattering. Here, a stitching strategy is adopted to fabricate an rGO/g-C3N4 film, where 2D g-C3N4 works as a linker to covalently connect adjacent rGO sheets for expanding the size of graphene and forming an in-plane rGO/g-C3N4 heterostructure. The in-plane thermal conductivity of the rGO/g-C3N4 film reaches 41.2 W m–1 K–1 at a g-C3N4 content of only 1 wt %, which increased by 17.3% compared to pristine rGO. The interfaced thermal resistance between rGO and g-C3N4 is further examined by non-equilibrium molecular dynamics simulations. Furthermore, owing to the unique light absorption and welding ability of g-C3N4, the rGO/g-C3N4 film presents superior solar-thermal and electric-thermal responses to controllably regulate the chip temperature against overcooling. This work provides a facile approach to construct a large-sized rGO sheet and combines heat dissipation and heating capability in the same thermal management material for future electronics.