Enhanced high-temperature thermal conductivity of the reduced graphene oxide@SiO2 composites synthesised by liquid phase deposition

Liquid phase deposition was developed to synthesise thermally conductive reduced graphene oxide@SiO 2 (rGO@SiO 2 ) composites for use in aerobic environments above 600 °C. This method is a mild, controllable reaction, good repeatability, easy operation, and low cost. The composition, morphology, oxidation resistance property, thermal conductivity (TC) property, and deposition dynamics of the rGO@SiO 2 composites were systematically investigated in this study. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy and high-resolution X-ray photoelectron spectroscopy (XPS) measurements proved that SiO 2 particles were synthesised on the rGO. Spherical SiO 2 particles were uniformly dispersed on both sides of the rGO, the SiO 2 particle size was relatively uniform (∼500 nm), and there was no excessive aggregation. Isothermal oxidation and TC analyses showed that the rGO@SiO 2 composite possessed better high-temperature and oxidation-resistance properties compared to pristine rGO, while still exhibiting excellent TC in the out-of-plane direction (k ⊥ ) at 650 °C after 24 h. Moreover, the deposition dynamics of the rGO@SiO 2 composite were established based on the analysis results. The synthesis method, liquid phase deposition, provides a promising route for the mild and controllable synthesis of rGO-ceramic composites for thermal management materials.