Simultaneous enhancement of thermoelectric and mechanical performance for SnTe by nano SiC compositing

Abstract

SiC is firstly introduced into SnTe. The created lattice mismatch and interfaces via hand milling are responsible for the enhanced zT, which is comparable with doped samples. Besides, the hardness of samples is got improved with SiC compositing.

Physical Insights on the Lattice Softening Driven Mid‐Temperature Range Thermoelectrics of Ti/Zr‐Inserted SnTe—An Outlook Beyond the Horizons of Conventional Phonon Scattering and Excavation of Heikes’ Equation for Estimating Carrier Properties

“…At the mid‐low temperature regime, the log[σ] for the optimized Ti/Zr doped compositions display T –0.25 dependence, suggesting the possibilities for “mixed scattering mechanisms” in this low‐temperature domain, which is known to dominate when the temperature exponent reaches close to 0. [ 73–75 ] At a higher temperature regime, a steep reduction of log[σ] is observed with a larger slope (≈ T –0.8 − T –0.97 ), which can be attributed to the additional acoustic phonon scattering, as the phonon concentration ( n ph ) generally increases with T . [ 75,76 ] Thus, the mixed scattering mechanisms can explain the rationale behind increased μ w (Figure 9) especially at the mid‐low temperature ranges).…”

“…At the mid-low temperature regime, the log[σ] for the optimized Ti/ Zr doped compositions display T -0.25 dependence, suggesting the possibilities for "mixed scattering mechanisms" in this low-temperature domain, which is known to dominate when the temperature exponent reaches close to 0. [73][74][75] At a higher temperature regime, a steep reduction of log[σ] is observed with a larger slope (≈T -0.8 − T -0.97 ), which can be attributed to the additional acoustic phonon scattering, as the phonon concentration (n ph ) generally increases with T. [75,76] Thus, the mixed scattering mechanisms can explain the rationale behind increased μ w (Figure 9) especially at the mid-low temperature ranges). In the past, such strategical tuning of carrier scattering mechanisms has been reported to improve the PF for n-type Mg 3 Sb 2 -based materials, where the mobility was enhanced by converting the ionized scattering into mixed scattering between ionization (σ ∝ T 1.5 ) and acoustic phonon scattering (σ ∝ T −1.5 ), which less effectively scatters the carriers.…”

Enhanced Thermal Conductivity of Polymer Composite by Adding Fishbone-like Silicon Carbide

“…However, most polymers exhibit typically poor thermal conductivity, such as the thermal conductivity of polyvinylidene fluoride (PVDF), polydimethylsiloxane (PDMS), polystyrene (PS), etc., ranging from 0.1 to 0.4 W m −1 K −1 [15], which significantly limits their applications as TIMs. In order to solve this problem, functional fillers of different shapes and types with high thermal conductivity are added into polymers to improve the heat transportation efficiency [16][17][18][19][20][21][22][23]. Wang et al enhanced the thermal conductivity of carbon fiber/polymer composites through SiC nanowires/graphene hybrid nanofillers [24].…”

Current State‐of‐the‐Art in the Interface/Surface Modification of Thermoelectric Materials

“…Among the several types of second phases that have been incorporated into TE materials to enhance their zT value, silicon carbide nanoparticles have attracted significant interest. Many semiconductors, such as SiC, [ 131–142 ] MgB 2 , [ 143,144 ] TiN, [ 145,146 ] B, [ 147–149 ] and others, [ 150–152 ] have been confirmed to improve both the mechanical and thermoelectric performance of TE materials.…”

“…[ 157,158 ] Also, nanoparticle dispersion aids in the dislocation of pile‐up stresses and hinders the generation of cracks, as well as their further propagation, thereby strengthening the fracture toughness. [ 132,134,136,159 ] The presence of second phases can trigger the generation of porosities, however, impacting in the process the relative density and, by extension, material hardness. [ 154 ]…”