Search

Graphene nanoplatelets (GNP) are just one of the attractive graphene-based nanomaterials that are rapidly emerging and have sparked the interest of many industries. These small stacks of platelet-shaped graphene sheets have a unique size and morphology that quickly disperse into other materials such as polymers, resulting in higher-value composite materials with improved thermal, conductivity, and mechanical capabilities. A detailed analysis of reinforced High-Density Polyethylene (HDPE) using different sizes (2, 15, 25 μm) and compositions (8, 10, 15 wt.%) of Graphene Nanoplatelets (GNP) has been conducted. The microstructure of the HDPE/GNP nanocomposites was extensively examined during the melt blending and injection moulding processes. Based on the results, the nanocomposites with different sizes of GNP exhibited dissimilar behaviour with different compositions. Furthermore, scanning electron microscope (SEM) results indicated a homogeneous dispersion for GNP in melt mixing. Moreover, thermogravimetric (TG) data demonstrate that increasing filler showed a slight increase in the material's thermal stability. The use of GNP improved mechanical properties, as evidenced by the increases in Young's modulus of yield strength from around 100 MPa to over 400 MPa. This study provides a practical reference for the industrial preparation of polymer-based graphene nanocomposites. [ABSTRACT FROM AUTHOR]

In this work, an optothermal wave characterization based on the photoacoustic (PA) technique was first implemented to investigate the thermal and carrier transport properties of Au thin film layer deposited on Si wafers (Au/Si) annealed at different temperatures. The XRD pattern showed that a metastable gold (Au) silicide of Au81Si19 phase formation was traced at annealing temperature of 330 oC and this structure disappeared when the temperature was further elevated up to 370 oC. The result showed that the PA signal obtained for Au/Si structure was lower than the pure Si wafer. The thermal and carrier transport properties of Si and Au/Si were elucidated from the fitting of PA signalphase relation. From the result, the thermal diffusivity and surface recombination velocity of Au/Si increased with shorter recombination lifetime as the raise of annealing temperature. Nonetheless, as the temperature approaches 370 °C, the surface recombination and thermal transport process diminishes, which may be ascribed to the rupture of silicide clusters. [ABSTRACT FROM AUTHOR]