A huge concern regarding global warming, as well as the depletion of natural fuel resources, has led to a wide search for alternative energy sources. Due to their high reliability and long operation time, thermoelectric generators are of significant interest for waste heat recovery and power generation. The main disadvantage of TEGs is the low efficiency of thermoelectric commercial modules. In this work, a unique design for a multilayer TE unicouple is suggested for an operating temperature range of 50–600 °C. Two types of thermoelectric materials were selected: «low temperature» n-and p-type TE materials (for the operating temperature range of 50–300 °C) based on Bi2Te3 compounds and «middle temperature» (for the operating temperature range of 300–600 °C) n- and p-type TE materials based on the PbTe compound. The hot extrusion technology was applied to fabricate n- and p-type low-temperature TE materials. A unique design of multilayer TEG was experienced to achieve an efficiency of up to 15%. This allows for the possibility of extracting this amount of electrical power from the heat generated for domestic and water heating. 

https://www.mdpi.com/1996-1073/15/11/3960/pdf?version=1653645347

Development of a High Perfomance Gas Thermoelectric Generator (TEG) with Possibible Use of Waste Heat

Triboelectric nanogenerator (TENG) can convert tiny mechanical energy into precious electrical energy. Constant improvements to the output performance of TENG is not only the driving force for its sustainable development, but also the key to expand its practical applicability in modern smart devices. However, most previous studies were conducted at room temperature, ignoring the influence of temperature on the output performance of TENG. Additionally, due to thermionic emission effect, the electrons transferred to a dielectric surface can be released into a vacuum after contact electrification. Therefore, TENG cannot maintain an effective electrical output under high-temperature conditions. Here, a series of high-temperature operatable flexible TENGs (HO-TENGs) based on nanofiber/microsphere hybrid membranes (FSHMs) was fabricated by electrospinning and electrospraying. The Voc of HO-TENG is 212 V, which is 2.33 times higher than that of control TENG. After 10,000 cycle stability tests, the HO-TENG shows excellent durability. Especially, this HO-TENG can maintain 77% electrical output at 70 °C compared to room temperature, showing excellent high-temperature operability. This study can not only provide a reference for the construction of advanced high-performance TENG, but also provide a certain experimental basis for efficient collection of mechanical energy in high-temperature environment and promote the application of TENG devices in harsh environments.

/pdf/harsh-environmental-tolerant-and-high-performance-ctll60qb.pdf

Harsh Environmental-Tolerant and High-Performance Triboelectric Nanogenerator Based on Nanofiber/Microsphere Hybrid Membranes

Recent advances in thermoelectric performance by incorporating graphene-based materials for energy harvesting

Amongst thermoelectrics, Bi2Te3 is special owing to its peak performance near room temperature, which enables it to be used for both energy harvesting and cooling. Despite the extensive studies on...

/pdf/enhanced-thermoelectric-performance-bi0-5sb1-5te3-sic-vriwxyif.pdf

Enhanced Thermoelectric Performance Bi0.5Sb1.5Te3/SiC Composites Prepared by Low-temperature Liquid Phase Sintering

The effect of powder synthesis method on thermoelectric properties of Bi2Te2.7Se0.3 thin films

Development of the high performance thermoelectric unicouple based on Bi2Te3 compounds

Abstract: Due to the increase in energy demand and depletion of natural resources, the development of energy harvesting technologies becomes very important. Thermoelectric devices, based on the direct conversion of heat into electrical energy, are being the essential part of cost-effective, environmental-friendly, and fuel-saving energy sources for power generation, temperature sensors, and thermal management. High reliability and long operation time of thermoelectric energy systems lead to their extensive use in space industry and gas pipe systems. Development and wide application of solar thermoelectric converters (generators) is mainly limited by relatively low thermoelectric conversion efficiency. In this work, we suggest for the first time to use direct conversion of solar energy by systems based on high-performance multistage thermoelectric modules operating in the temperature range of 300 - 900 K for creation of autonomic systems with electric power up to 500 W and electric efficiency up to 15 %. Furthermore, we developed film thermoelectric modules on thin flexible substrates with the figure of merit Z corresponding to that of bulk modules. Such film thermoelectric converters with output voltage of several volts and electric power of several microwatts can be used at micro-solar energy systems.

Development of Solar Energy Systems Based on High Performance Bulk and Film Thermoelectric Modules

We calculated the mean atomic kinetic energy, , of the X atom (X = Si, Ti, Hf, O) in some ceramic oxides, SiO2, TiO2 and HfO2 using the published partial vibrational density of states (PVDOS). These were simulated by means of lattice dynamics, molecular dynamics and density functional theory. The predicted values are compared to those recently obtained by electron Compton scattering (ECS), with an overall good agreement of ~4%. In accord with calculations, the ECS measurements reveal a small, but detectable, dependence of on the fine structural details of the oxide, e.g. whether it is in a crystalline or amorphous form, and whether it exhibits surface or bulk characteristics. This study illustrates the limitations and the potential of PVDOS simulations in predicting experimental atomic kinetic energies, and can be viewed as a promising approach for elucidating valuable structural and dynamical information of ceramic oxides and other materials.

/pdf/on-the-atomic-kinetic-energies-in-ceramic-oxides-1qttgmx40b.pdf

Rony Shneck

Papers

Development of the high performance thermoelectric unicouple based on Bi2Te3 compounds

Development of Solar Energy Systems Based on High Performance Bulk and Film Thermoelectric Modules

On the Atomic Kinetic Energies in Ceramic Oxides