Grain boundary re-crystallization and sub-nano regions leading to high plateau figure of merit for Bi₂Te₃ nanoflakes

Abstract

Nanoengineering is an effective strategy to strengthen phonon scattering, reduce lattice thermal conductivity and boost thermoelectric material performance. However, nanostructure features are generally in the size of ~10 nm, and...

Decoupling Carrier-Phonon Scattering Boosts the Thermoelectric Performance of n-Type GeTe-Based Materials

“…The κ decreases over the entire temperature region with increasing t a , which is contributed by the synergistic reduction of κ e and κ l . The κ e depends on the electrical properties and is defined as κ e = LσT , where L is the Lorenz factor Figure S5b (Supporting Information) provides the temperature-dependent L of Ge 0.67 Pb 0.13 Bi 0.2 Te.…”

“…From the electrical performance viewpoint, aliovalent doping and band engineering can enhance the S 2 σ by optimizing the carrier concentration ( n ) and increasing the carrier mobility ( μ ). , From the thermal performance viewpoint, defect engineering can suppress the κ l by enhancing phonon scattering. − Based on these strategies, the ZT of many thermoelectric materials, such as Bi 2 Te 3 , − PbTe, , GeTe, − PbSe, − and Cu 2 Se, , is extensively enhanced. However, the coupled relationship between carrier (contributing to μ ) and phonon scattering (contributing to κ l ) still severely limits the enhancement of ZT .…”

“…The κ e depends on the electrical properties and is defined as κ e = LσT, where L is the Lorenz factor. 15 Figure S5b (Supporting Information) provides the temperature-dependent L of Ge 0.67 Pb 0.13 Bi 0.2 Te. Figure 5b shows the temperature-dependent κ e of Ge 0.67 Pb 0.13 Bi 0.2 Te for different t a values.…”

Carrier Control of Bi-Doped SnSe Films for Fabrication of π-Type Thermoelectric Film Modules

“…The efficiency and output power of the module depend on the thermoelectric materials as well as on these module parameters. The output power and the conversion efficiency are determined by the power factor, PF = S 2 σ, and the dimensionless figure of merit ( ZT = S 2 σ T /κ), where S , σ, κ, and T are the Seebeck coefficient, electrical conductivity, thermal conductivity, and temperature, respectively. , The power factor and ZT strongly depend on the thermoelectric material, and ZT in the thermoelectric materials is improved by reducing the thermal conductivity. The contact resistance is also important to experimentally realize the expected performance in the thermoelectric module …”

Review of Piezoelectric Properties and Power Output of PVDF and Copolymer-Based Piezoelectric Nanogenerators

“…With the increased push towards clean sustainable forms of energy, methods to convert ambient energy into useable electricity are being developed such as piezoelectric, thermoelectric, and triboelectric energy harvesters [1,2]. Due to the way dipoles are arranged in piezoelectric materials, they can transform mechanical energy (vibrations) into electrical energy and thus offer a way to harvest ambient mechanical energy.…”