Layered structure of alumina/graphene-augmented-inorganic-nanofibers with directional electrical conductivity

Thermal Transport and Thermoelectric Effect in Composites of Alumina and Graphene-Augmented Alumina Nanofibers

“…However, under the employed sintering parameters, none of the samples demonstrate features of a vermicular structure. A discussion on the sintering temperature and its effect on the microstructure of GAIN/Al 2 O 3 is detailed in [ 40 ]. The GAIN fillers are visibly located at the grain boundaries with a slight preferential orientation which is more pronounced for the composites of the high filler contents.…”

“…The K L can be correlated to phonon mean free path ( λ ) using Equation (2), in which C p is the specific heat capacity, and V is the phonon group velocity of the bulk material [ 45 ]. The phonon group velocity of the bulk can be determined using Equation (3), where ρ is the bulk density, and E is the elastic modulus, attained from the previous paper of the authors [ 40 ]. The values of λ are presented in Figure 4 c for both in-plane and through-plane directions.…”

“…The bandgap was calculated from the slope of the Arrhenius plot for bulk composites with 1–25 wt.% GAIN and ranges from 1.0 to 0.6 meV. Previously it was shown that both carrier types are present in the GAIN/alumina structures owing to the n -type GAIN fillers and the p -doping of the matrix alumina in the presence of point defects such as Al interstitials and O vacancies [ 40 ]. The positive values of the Seebeck coefficient in Figure 6 c prove that the majority carriers are p -type.…”

“…However, increasing mobility and decreasing bandgap are associated with augmenting both σ and S [ 1 ]. Increasing carrier mobility and carrier density was established as a function of GAIN content [ 40 ]. Therefore, in the sample with the highest GAIN content (25 wt.%), and correspondingly higher carrier density and mobility, an overall higher S is achieved which peaks at 18 µ · V · K −1 at 350 K. Similar values were obtained for 17 vol.% GNP-Si 3 N 4 composites [ 51 ].…”

SiC Nanowire–Si3N4 Nanobelt Interlocking Interfacial Enhancement of Carbon Fiber Composites with Boosting Mechanical and Frictional Properties

“…Third, the architecture design of nanofillers should be considered. The designed shape and structure are most important aspects to realize the unique mechanical behaviors. − Specially, the interlocking architecture can give full opportunity to enhance of nanofiller and greatly improve the mechanical properties of composite materials. Taking into account the above-mentioned issues, the introduction of a two-component silicon-based interlocking enhancement (SiCnws and Si 3 N 4 nbs) into CC should be a promising strategy to achieve simultaneous reinforcement for fiber/matrix interface and PyC matrix.…”