Infinite coordination polymer for enhancing the thermoelectric performance of Bi0.5Sb1.5Te3 for low-grade waste heat recovery

Thermoelectric Performance Enhancement in Commercial Bi0.5Sb1.5Te3 Materials by Introducing Gradient Cu-Doped Grain Boundaries

“…For the polycrystalline bulk TE material, grain boundaries play multiple roles in the phonon/carrier transportation. Under normal conditions, the grain boundary acts as a potential barrier, which leads to an interfacial resistance due to the energy-filtering effect. ,, In the present work, the energy filtering as well as Cu doping at the grain boundary all affect the electron transport behaviors of the as-prepared sample. Thus, the two-phase model consisting of the grain phase and the grain boundary phase is used to analyze the carrier/phonon transport behaviors of the as-prepared sample. , The additional interfacial electrical resistance originated from the gradient Cu-doped grain boundary (ρ ad‑gb ) is estimated, as shown in Figure a.…”

“…According to previous reports, introducing Cu doping to BST could decrease κ latt by enhancing the phonon scattering from point defects and suppressing the contribution of minor carrier concentrations (electrons). 10,34 In the present work, the κ latt of the BC2 (0.5 W/mK) is 21.9% lower than that of D-BST (0.64 W/mK), which could be ascribed to the enhanced phonon scattering at Cu-doped grain boundaries. Consequently, the maximum ZT reaches ∼1.29 at 375 K, and a prominent average ZT of ∼1.18 (350∼475 K) is attained in the BC2 sample, which shows superiority when compared with that of D-BST and BST (Figure 2e).…”

“…Under normal conditions, the grain boundary acts as a potential barrier, which leads to an interfacial resistance due to the energy-filtering effect. 23,34,35 In the present work, the energy filtering as well as Cu doping at the grain boundary all affect the electron transport behaviors of the as-prepared sample. Thus, the two-phase model consisting of the grain phase and the grain boundary phase is used to analyze the carrier/phonon transport behaviors of the as-prepared sample.…”

Hierarchical Phonon Scattering from Nano to Macro Scale in Ag-Nano/TiO2-Micro Particle-Decorated p-type Bismuth Telluride Bulk Composites

“…Many Ag-TiO 2 particles are distributed in the BST matrix, as presented in Figure f. Small-size particle distribution on the matrix can scatter phonons, which is beneficial to reducing thermal conductivity …”

“…Small-size particle distribution on the matrix can scatter phonons, which is beneficial to reducing thermal conductivity. 33 Figure 7 depicts the temperature-dependent thermoelectric properties of the BST composite with US-Ag/TiO 2 particles synthesized by Us and spark plasma sintering. Figure 7a shows the temperature-dependent electrical resistivity of the samples, indicating metallic or degenerated semiconducting behavior with temperature.…”