Piezoelectric-Augmented Thermoelectric Ionogels for Self-Powered Multimodal Medical Sensors.

A paradigm ionogel consisting of ionic liquid (IL) and PVDF-HFP composites is made, which inherently possesses dual-function ionic thermoelectric (iTE) and piezoelectric (PE) attributes. This study investigates an innovative "PE-enhanced iTEs" effect, wherein the ionic thermopower exhibits a 58% enhancement while the ionic conductivity arises more than 2× within a PE-induced internal electric field. By harnessing these multifaceted features, fully self-powered, multimodal sensors demonstrate their superior energy conversion capabilities, which possessed minimum sensitivities of 0.

Advancing Thermoelectric Performance of BiTe below 400 K.

Thermoelectric cooling devices utilizing BiTe-based alloys have seen increased utilization in recent years. However, their thermoelectric performance remains inadequate within the operational temperature range (≤400 K), with limited research addressing this issue. In this study, we successfully modulated the carrier concentration of the sample through Te content reduction, consequently lowering the peak temperature of the value from 400 to 300 K.

Lead-free and scalable GeTe-based thermoelectric module with an efficiency of 12.

GeTe-based materials with superior thermoelectric properties promise great potential for waste heat recovery. However, the lack of appropriate diffusion barrier materials (DBMs) limits not only the energy conversion efficiency but also the service reliability of the thermoelectric devices. Here, we propose a design strategy based on phase equilibria diagrams from first-principles calculations and identify transition metal germanides (e.

Thermal-inert and ohmic-contact interface for high performance half-Heusler based thermoelectric generator.

Unsatisfied electrode bonding in half-Heusler devices renders thermal damage and large efficiency loss, which limits their practical service at high temperatures. Here, we develop a thermodynamic strategy to screen barrier layer elements. Theoretically, we found that the interface between VIIB elements and half-Heuslers possesses near-zero interfacial reaction energy and large atomic diffusion barrier.

Influence of Solvent-Dependent Morphology on Molecular Doping and Charge Transport in Conductive Thiophene Polymer.

The utility of a solvent is one of the key factors that impacts resultant film morphology. However, the effect of solvent-dependent morphology on the doping process and electrical conductivity has not been adequately elucidated. In this work, we compared the morphology of chloroform- and chlorobenzene-processed thiophene polymer films and investigated how the choice of solvent influences film morphology, doping level, charge transport properties, and thus electrical conductivity.

Enhanced Thermoelectric Performance in Ge Sb Te/FeGe Composites Enabled by Hierarchical Defects.

Manipulations of carrier and phonon scatterings through hierarchical structures have been proved to be effective in improving thermoelectric performance. Previous efforts in GeTe-based materials mainly focus on simultaneously optimizing the carrier concentration and band structure. In this work, a synergistic strategy to tailor thermal and electrical transport properties of GeTe by combination with the scattering effects from both Ge vacancies and other defects is reported.

High-entropy-stabilized chalcogenides with high thermoelectric performance.

Thermoelectric technology generates electricity from waste heat, but one bottleneck for wider use is the performance of thermoelectric materials. Manipulating the configurational entropy of a material by introducing different atomic species can tune phase composition and extend the performance optimization space. We enhanced the figure of merit () value to 1.

Electrode interface optimization advances conversion efficiency and stability of thermoelectric devices.

Although the CoSb-based skutterudite thermoelectric devices have been highly expected for wide uses such as waste heat recovery and space power supply, the limited long-term service stability majorly determined by the degradation of electrode interface obstructs its applications. Here, we built up an effective criterion for screening barrier layer based on the combination of negative interfacial reaction energy and high activation energy barrier of Sb migration through the formed interfacial reaction layer. Accordingly, we predicted niobium as a promising barrier layer.

Superior performance and high service stability for GeTe-based thermoelectric compounds.

GeTe-based compounds have been intensively studied recently due to their superior thermoelectric performance, but their real applications are still limited so far due to the drastic volume variation that occurs during the rhombohedral-cubic phase transition, which may break the material or the material/electrode interface during service. Here, superior performance and high service stability for GeTe-based thermoelectric compounds are achieved by co-doping Mg and Sb into GeTe. The linear coefficient of thermal expansion before phase transition is greatly improved to match that after phase transition, yielding smooth volume variation around the phase transition temperature.

Low Contact Resistivity and Interfacial Behavior of p-Type NbFeSb/Mo Thermoelectric Junction.

Half-Heusler compounds are a class of promising thermoelectric (TE) materials for power generation. However, the large contact resistivity at the interface between TE legs and metal electrode of the TE device seriously hinders the full play of the material performance. Here we report an Ohmic contact for the junction of p-type NbTiFeSb and Mo electrode with a low contact resistivity of <1 μΩ cm due to the matching of work functions between NbTiFeSb and FeMo interlayer.

Intrinsically High Thermoelectric Performance in AgInSe n-Type Diamond-Like Compounds.

Diamond-like compounds are a promising class of thermoelectric materials, very suitable for real applications. However, almost all high-performance diamond-like thermoelectric materials are p-type semiconductors. The lack of high-performance n-type diamond-like thermoelectric materials greatly restricts the fabrication of diamond-like material-based modules and their real applications.

Synthesis and Thermoelectric Properties of Charge-Compensated SPdCoSb Skutterudites.

Recently, the electronegative elements (e.g., S, Se, Cl, and Br) filled skutterudites have attracted great attention in thermoelectric community.

Realizing high figure of merit in heavy-band p-type half-Heusler thermoelectric materials.

Solid-state thermoelectric technology offers a promising solution for converting waste heat to useful electrical power. Both high operating temperature and high figure of merit zT are desirable for high-efficiency thermoelectric power generation. Here we report a high zT of ∼1.

Ultrahigh thermoelectric performance by electron and phonon critical scattering in Cu2 Se1-x Ix.

Iodine-doped Cu2 Se shows a significantly improved thermoelectric performance during phase transitions by electron and phonon critical scattering, leading to a dramatic increase in zT by a factor of 3-7 times culminating in zT values of 2.3 at 400 K.

Multiple-filled skutterudites: high thermoelectric figure of merit through separately optimizing electrical and thermal transports.

Skutterudites CoSb(3) with multiple cofillers Ba, La, and Yb were synthesized and very high thermoelectric figure of merit ZT = 1.7 at 850 K was realized. X-ray diffraction of the densified multiple-filled bulk samples reveals all samples are phase pure.