Flexible All-Inorganic Thermoelectric Yarns.

Achieving both formability and functionality in thermoelectric materials remains a significant challenge due to their inherent brittleness. Previous approaches, such as polymer infiltration, often compromise thermoelectric efficiency, underscoring the need for flexible, all-inorganic alternatives. This study demonstrates that the extreme brittleness of thermoelectric bismuth telluride (BiTe) bulk compounds can be overcome by harnessing the nanoscale flexibility of BiTe nanoribbons and twisting them into a yarn structure.

Chiral Twist Interface Modulation Enhances Thermoelectric Properties of Tellurium Crystal.

Manipulating the grain boundary and chiral structure of enantiomorphic inorganic thermoelectric materials facilitates a new degree of freedom for enhancing thermoelectric energy conversion. Chiral twist mechanisms evolve by the screw dislocation phenomenon in the nanostructures; however, contributions of such chiral transport have been neglected for bulk crystals. Tellurium (Te) has a chiral trigonal crystal structure, high band degeneracy, and lattice anharmonicity for high thermoelectric performance.

Suppressed Lone Pair Electrons Explain Unconventional Rise of Lattice Thermal Conductivity in Defective Crystalline Solids.

Manipulating thermal properties of materials can be interpreted as the control of how vibrations of atoms (known as phonons) scatter in a crystal lattice. Compared to a perfect crystal, crystalline solids with defects are expected to have shorter phonon mean free paths caused by point defect scattering, leading to lower lattice thermal conductivities than those without defects. While this is true in many cases, alloying can increase the phonon mean free path in the Cd-doped AgSnSbSe system to increase the lattice thermal conductivity from 0.

Advances in thermoelectric AgBiSe: Properties, strategies, and future challenges.

Thermoelectric materials are attracting considerable attention to alleviate the global energy crisis by enabling the direct conversion of heat into electricity. As a class of I-V-VI semiconductors, AgBiSe is expected to be the potential thermoelectric material to replace conventional PbTe-based compounds due to its non-toxic and abundant nature of its constituent elements. This review article summarizes the fundamental properties of AgBiSe, thermoelectric properties, the effect of different dopants on its transport properties and entropy engineering for cubic phase stabilization with the detailed description of related techniques used to analyze the properties of AgBiSe.

Suppressing Charged Cation Antisites via Se Vapor Annealing Enables p-Type Dopability in AgBiSe -SnSe Thermoelectrics.

Cation disordering is commonly found in multinary cubic compounds, but its effect on electronic properties has been neglected because of difficulties in determining the ordered structure and defect energetics. An absence of rational understanding of the point defects present has led to poor reproducibility and uncontrolled conduction type. AgBiSe is a representative compound that suffers from poor reproducibility of thermoelectric properties, while the origins of its intrinsic n-type conductivity remain speculative.

Heat-fueled enzymatic cascade for selective oxyfunctionalization of hydrocarbons.

Heat is a fundamental feedstock, where more than 80% of global energy comes from fossil-based heating process. However, it is mostly wasted due to a lack of proper techniques of utilizing the low-quality waste heat (<100 °C). Here we report thermoelectrobiocatalytic chemical conversion systems for heat-fueled, enzyme-catalyzed oxyfunctionalization reactions.

Fabrication of conductive silver paste recovered from leaching of waste catalyst using hydrochloric acid.

Transition metal compounds based on silver (Ag) and palladium (Pd) are extensively used as catalysts in the petrochemical industries. The catalytic activities of Ag and Pd decrease over time and hence need to be discarded. The recovery of elements like Ag from waste catalyst is essential because of its limited availability and cost, and it is environmentally beneficial with regards to recycling.

Comparative Study of Thermoelectric Properties of SbSiTe and BiSiTe.

Charge carrier transport and corresponding thermoelectric properties are often affected by several parameters, necessitating a thorough comparative study for a profound understanding of the detailed conduction mechanism. Here, as a model system, we compare the electronic transport properties of two layered semiconductors, SbSiTe and BiSiTe. Both materials have similar grain sizes and morphologies, yet their conduction characteristics are significantly different.

Enhanced thermoelectric properties of AgSbTe obtained by controlling heterophases with Ce doping.

We report the enhanced thermoelectric properties of Ce-doped AgSbTe (AgSbCeTe) compounds. As the Ce contents increased, the proportion of heterophase AgTe in the AgSbTe gradually decreased, along with the size of the crystals. The electrical resistivity and Seebeck coefficient were dramatically affected by Ce doping and the lattice thermal conductivity was reduced.

Erratum: A comparison of postoperative emergence agitation between sevoflurane and thiopental anesthesia induction in pediatric patients (Korean J Anesthesiol 2015 Aug; 68(4): 373-378).

[This corrects the article on p. 373 in vol. 68, PMID: 26257850.

Deposition of n-Type Bi2Te3 Thin Films on Polyimide by Using RF Magnetron Co-Sputtering Method.

Bi2Te3 thermoelectric thin films were deposited on the flexible polyimide substrates by RF magnetron co-sputtering of a Bi and a Te targets. The influence of the substrate temperature and RF power on the microstructure, chemical composition, and the thermoelectric properties of the sputtered films was investigated by using scanning electron microscopy, X-ray diffraction, energy dispersive X-ray spectroscopy, and in-plane resistivity/Seebeck coefficient measurement. It was shown that the thermoelectric properties of the films depend sensitively on the Bi/Te chemical composition ratio and the substrate temperature, and the layered structure was clearly observed from the cross section of the (00L)-oriented, nearly stoichiometric Bi2Te3 films when the substrate temperature is higher than 250 °C.

A comparison of postoperative emergence agitation between sevoflurane and thiopental anesthesia induction in pediatric patients.

Background: This study was performed to compare the incidence of emergence agitation (EA) between inhalation and intravenous anesthesia induction in children after sevoflurane anesthesia.

Methods: In this prospective and double-blind study, 100 children aged 3 to 7 years were enrolled. Subjects were randomly assigned to the sevoflurane (Group S) or thiopental (Group T) anesthesia induction groups.

Correction: Three-dimensional hierarchical Te-Si nanostructures.

Correction for 'Three-dimensional hierarchical Te-Si nanostructures' by Jae-Hong Lim et al., Nanoscale, 2014, 6, 11697-11702.

Fabrication of high-quality single-crystal Cu thin films using radio-frequency sputtering.

Copper (Cu) thin films have been widely used as electrodes and interconnection wires in integrated electronic circuits, and more recently as substrates for the synthesis of graphene. However, the ultra-high vacuum processes required for high-quality Cu film fabrication, such as molecular beam epitaxy (MBE), restricts mass production with low cost. In this work, we demonstrated high-quality Cu thin films using a single-crystal Cu target and radio-frequency (RF) sputtering technique; the resulting film quality was comparable to that produced using MBE, even under unfavorable conditions for pure Cu film growth.

Three-dimensional hierarchical Te-Si nanostructures.

Three-dimensional hybrid nanostructures (i.e., Te "nanobranches" on a Si "nanotrunk" or Te "nanoleaves" on a Si "nanotrunk") were synthesized by combining the gold-assisted chemical etching of Si to form Si "nanotrunks" and the galvanic displacement of Si to form Te "nanobranches" or "nanoleaves.

Abnormal drop in electrical resistivity with impurity doping of single-crystal Ag.

Resistivity is an intrinsic feature that specifies the electrical properties of a material and depends on electron-phonon scattering near room temperature. Reducing the resistivity of a metal to its potentially lowest value requires eliminating grain boundaries and impurities, but to date few studies have focused on reducing the intrinsic resistivity of a pure metal itself. We could reduce the intrinsic resistivity of single-crystal Ag, which has an almost perfect structure, by impurity doping it with Cu.

Gate-controlled spin-orbit interaction in inas high-electron mobility transistor layers epitaxially transferred onto Si substrates.

We demonstrate gate-controlled spin-orbit interaction (SOI) in InAs high-electron mobility transistor (HEMT) structures transferred epitaxially onto Si substrates. Successful epitaxial transfer of the multilayered structure after separation from an original substrate ensures that the InAs HEMT maintains a robust bonding interface and crystalline quality with a high electron mobility of 46200 cm(2)/(V s) at 77 K. Furthermore, Shubnikov-de Haas (SdH) oscillation analysis reveals that a Rashba SOI parameter (α) can be manipulated using a gate electric field for the purpose of spin field-effect transistor operation.

Lossless hybridization between photovoltaic and thermoelectric devices.

The optimal hybridization of photovoltaic (PV) and thermoelectric (TE) devices has long been considered ideal for the efficient harnessing solar energy. Our hybrid approach uses full spectrum solar energy via lossless coupling between PV and TE devices while collecting waste energy from thermalization and transmission losses from PV devices. Achieving lossless coupling makes the power output from the hybrid device equal to the sum of the maximum power outputs produced separately from individual PV and TE devices.