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Manipulating and integrating the microstructures at different scales is crucial to tune the electrical and thermal properties of a given compound. High-pressure sintering can modify the multiscale microstructures and thus empower the cutting-edge thermoelectric performance. In this work, the high-pressure sintering technique followed by annealing is adopted to prepare Gd-doped p-type (Bi0.2Sb0.8)2(Te0.97Se0.03)3alloys. First, the high energy of high-pressure sintering promotes the reduction of grain size, thus increasing the content of 2D grain boundaries. Next, high-pressure sintering induces strong interior strain, where 1D dense dislocations are generated near the strain field. More interestingly, the rare-earth element Gd with a high melting temperature is dissolved into the matrix via high-pressure sintering, thus promoting the formation of 0D extrinsic point defects. This concurrently improves the carrier concentration and density-of-state effective mass, resulting in an enhanced power factor. In addition, the integrated 0D point defects, 1D dislocations, and 2D grain boundaries by high-pressure sintering strengthen phonon scattering, thereby achieving a low lattice thermal conductivity of 0.5 Wm–1K–1at 348 K. Consequently, a maximum zTvalue of ∼1.1 at 348 K is achieved in the 0.4 at % Gd-doped (Bi0.2Sb0.8)2(Te0.97Se0.03)3sample. This work demonstrates that high-pressure sintering enables microstructure modification to enhance the thermoelectric performance of Bi2Te3-based and other bulk materials.

• Se replacement can enlarge the E g and thus effectively mitigate the bipolar effect. • The manipulation of donor-like effect retains the optimized carrier concentration. • The large strain field and mass fluctuation reduce lattice thermal conductivity. • A state-of-the-art zT = 1.0 at 300 K is attained for n -type Bi 1.5 Sb 0.5 Te 2.8 Se 0.2. • n -type Bi 2- x Sb x Te 3 becomes a promising candidate for solid-state cooling field. To date, the benchmark Bi 2 Te 3 -based alloys are still the only commercial material system used for thermoelectric solid-state refrigeration. Nonetheless, the conspicuous performance imbalance between the p -type Bi 2- x Sb x Te 3 and n -type Bi 2 Te 3- x Se x legs has become a major obstacle for the improvement of cooling devices to achieve higher efficiency. In our previous study, novel n -type Bi 2- x Sb x Te 3 alloy has been proposed via manipulating donor-like effect as an alternative to mainstream n -type Bi 2 Te 3- x Se x. However, the narrow bandgap of Bi 2- x Sb x Te 3 provoked severe bipolar effect that constrained the further improvement of zT near room temperature. Herein, we have implemented band gap engineering in n -type Bi 1.5 Sb 0.5 Te 3 by employing isovalent Se substitution to inhibit the undesired intrinsic excitation and achieve the distinguished room-temperature zT. First, the preferential occupancy of Se at Te2 site appropriately enlarges the band gap, thereby concurrently improving the Seebeck coefficient and depressing the bipolar thermal conductivity. In addition, the Se alloying mildly suppresses the compensation mechanism and essentially preserves the already optimized carrier concentration, which maintains the peak zT near room temperature. Moreover, the large strain field and mass fluctuation generated by Se alloying leads to the remarkable reduction of lattice thermal conductivity. Accordingly, the zT value of Bi 1.5 Sb 0.5 Te 2.8 Se 0.2 reaches 1.0 at 300 K and peaks 1.1 at 360 K, which surpasses that of most well-known room-temperature n -type thermoelectric materials. These results pave the way for n -type Bi 2- x Sb x Te 3 alloys to become a new and promising top candidate for large-scale solid-state cooling applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Group IV–VI semiconductors, such as PbTe, GeTe and SnTe, are promising thermoelectric materials at intermediate temperatures, which have potential application in electrical generation from waste heat. A phase diagram plays an important role for designing a high-performance material. In this mini review, we present the enhancement of the thermoelectric properties of GeTe- and SnTe-based semiconductors based on their phase diagrams. The figure of merit ZTfor the p-type GeTe–Ag8GeTe6composites was enhanced by reducing the thermal conductivity significantly using the eutectic microstructures formed by the Ag8GeTe6second phase and the GeTe matrix based on the GeTe–Ag8GeTe6pseudo-binary system. The partial substitution of Te by Se in p-type GeTe extends the solid solubility of Pb in GeTe0.5Se0.5up to 30 mol.%, which further improves the thermoelectric properties of alloys in the GeTe–PbTe–Se system by modifying the carrier concentration, leading to increasing the Seebeck coefficient and reducing thermal conductivity over a wide composition range. The Sn1−yMnyTe alloy with 10 at.% excess Mn keeps its composition change along the SnTe–MnTe tie line and receives higher solid solubility of MnTe in SnTe. It shows much higher thermoelectric performance since the excess Mn compensates the Mn lost during the preparation as compared to the Sn1−xMnxTe alloy without excess Mn.

The table-like magnetocaloric effect is significant for the magnetic refrigeration applications above 20 K based on the Ericsson cycle. Herein, we prepared a series of Nd6Fe13Pd1–xCux(x = 0.05, 0.1, 0.15) compounds by the arc-melting method. These compounds show the single crystalline phase in the tetragonal Nd6Fe13Si-type structure with the space group I4/mcm. A magnetic phase transition from ferromagnetism to antiferromagnetism and a metamagnetic transition from the antiferromagnetic state to the ferromagnetic state are observed in each of the compounds. The compounds exhibit table-like magnetocaloric effects with large refrigerant capacities. A constant ΔSMin a temperature span of 40 K in the Nd6Fe13Pd0.85Cu0.15compound are observed. For a field change of 0–5 T, the peak values of –ΔSMfor the Nd6Fe13Pd0.95Cu0.05, Nd6Fe13Pd0.90Cu0.10, and Nd6Fe13Pd0.85Cu0.15compounds are estimated to be 4.8, 4.6 and 4.4 J/(kg·K) with corresponding refrigerant capacity values of 323, 331 and 316 J/kg, respectively. The obtained table-like magnetocaloric effects with large refrigerant capacities as well as fairly small thermal and magnetic hysteresis deem these series of compounds good candidates for single-phase magnetic refrigeration based on the Ericsson cycle.

Drought is expected to increase in temperate regions in the coming decades due to global climate change and will strongly affect nitrogen (N) transformation and balance. However, the underlying mechanisms (soil microenvironment vs. biotic community) of rainfall reduction induced changes in soil Ntransformation rates, and whether the responses of soil Ntransformation rates to rainfall reduction vary over time remains poorly understood. In this study, we experimentally examined rainfall reduction effects on soil Ntransformation rates over two (the second and third experimental years) growing‐seasons in a temperate meadow. We applied four treatments: ambient rainfall, 30%, 50%, and 70% reduction in rainfall. Our findings demonstrated that, 70% rainfall reduction significantly decreased the average net Nmineralization and nitrification rates by 68.4% and 72.0%, respectively. Soil nitrous oxide emission was profoundly varied between the experimental years, with it was sensitive no only to changes in annual precipitation amount, but also to seasonal distribution, the highest emissions appeared at the early growing‐season. Moreover, plant diversity, microbial biomass, and soil NO3−‐N content mainly regulated soil Ntransformation rates in response to rainfall reduction in the greater annual precipitation year; but soil Ntransformation rates were mainly controlled by soil water content in the less annual precipitation year. We suggest that to accurately project future ecosystem functions and improving the prediction of Ncycling responses to changing precipitation patterns, stronger focus should be allocated not only to changes in precipitation amounts, but also to inter‐ and intra‐annual differences in precipitation distribution. The variation in precipitation regimes may have profound impacts on soil Ncycling. To understand how the soil Ntransformation rates respond to different rainfall levels, we used rainout shelters to simulate reduced precipitation amount in a temperate meadow. We examined a suite of soil Ntransformations responses. Our results showed that soil Ntransformation rates decreased along the gradient of declining in rainfall amount over the two sampling years, with inter‐ and intra‐annual variation in precipitation distribution also played important roles in determining soil Ntransformation rates. The high values of each soil Ntransformation rates were appeared at different periods of the growing‐seasons. We also examined the pathways associated with the responses of soil Ntransformation rates to rainfall reduction in the two contrasting precipitation years. In summary, we conclude that rainfall reduction led to reductions in soil Ntransformation rates through a combination of plant, microbial, and soil factors during the greater annual precipitation. Nonetheless, in the less annual precipitation, the key factor determining Ntransformations was found to be soil water content. These findings offer valuable insights for forecasting interactions within the plant‐microbe‐soil Ncycling system under forthcoming precipitation patterns within the context of climate change. The high soil Ntransformation rates corresponded to a certain precipitation range at regional scaleRainfall reduction decreased soil Ntransformation rates via changing plant, microbial, and soil factors in greater precipitation yearSoil water content was the key factor determining soil Ntransformation rates, especially in less precipitation year The high soil Ntransformation rates corresponded to a certain precipitation range at regional scale Rainfall reduction decreased soil Ntransformation rates via changing plant, microbial, and soil factors in greater precipitation year Soil water content was the key factor determining soil Ntransformation rates, especially in less precipitation year

As an endogenous material genetic property, entropy is an emerging fingerprint factor in the material genome. By designing multicomponent thermoelectric materials with high configuration entropy, the lattice thermal conductivity can be significantly reduced viasevere lattice distortion, and the Seebeck coefficient can be improved by enhancing the crystal symmetry. However, high entropy also causes the deterioration of carrier mobility, restraining the improvement of the dimensionless figure of merit zT.Herein, we design the (GeTe)1−x(AgSb0.5Bi0.5Te2)x, aka TABGS alloys, viareplacing half of the Sb by Bi in the well-known (GeTe)1−x-(AgSbTe2)x, aka TAGS alloys, to attest the efficacy of entropy engineering. In view of the low carrier mean free path of TAGS alloys approaching to the Mott-Ioffe-Regel limit, further Bi substitution and increased configuration entropy cannot impair the carrier mobility any longer. In addition, the suppressed rhombohedral-cubic phase transition viahigh configuration entropy and the reduced carrier concentration contribute to the substantially improved Seebeck coefficient. Furthermore, the elicited multiscale microstructures and the decreased sound velocity upon AgSb0.5Bi0.5Te2alloying effectively restrain the lattice thermal conductivity. As a result, (GeTe)0.80(AgSb0.5Bi0.5Te2)0.20achieves a high zTof 1.60 at 723 K and an average zTaveof 1.23 from 300 to 773 K. Meantime, its room-temperature Vickers hardness reaches 2.21 GPa due to solid solution hardening. These results highlight the efficacy of entropy engineering in enhancing the thermoelectric performance, especially for numerous materials with intrinsically low carrier mobility.

Recent studies show that biomaterials are capable of regulating immune responses to induce a favorable osteogenic microenvironment and promote osteogenesis and angiogenesis. In this study, we investigated the effects of zinc silicate/nanohydroxyapatite/collagen (ZS/HA/Col) scaffolds on bone regeneration and angiogenesis and explored the related mechanism. We demonstrate that 10ZS/HA/Col scaffolds significantly enhanced bone regeneration and angiogenesis in vivocompared with HA/Col scaffolds. ZS/HA/Col scaffolds increased tartrate-resistant acid phosphatase (TRAP)-positive cells, nestin-positive bone marrow stromal cells (BMSCs) and CD31-positive neovessels, and expression of osteogenesis (Bmp-2 and Osterix) and angiogenesis-related (Vegf-αand Cd31) genes increased in nascent bone. ZS/HA/Col scaffolds with 10 wt % ZS activated the p38 signaling pathway in monocytes. The monocytes subsequently differentiated into TRAP+cells and expressed higher levels of the cytokines SDF-1, TGF-β1, VEGF-α, and PDGF-BB, which recruited BMSCs and endothelial cells (ECs) to the defect areas. Blocking the p38 pathway in monocytes reduced TRAP+differentiation and cytokine secretion and resulted in a decrease in BMSC and EC homing and angiogenesis. Overall, these findings demonstrate that 10ZS/HA/Col scaffolds modulate monocytes and, thereby, create a favorable osteogenic microenvironment that promotes BMSC migration and differentiation and vessel formation by activating the p38 signaling pathway.

To achieve high-performance thermoelectric (TE) devices, constructing a good interfacial connection between TE materials and electrodes is as important as having high figure-of-merit TE materials. Although CoSb3-based TE devices have received great attention for power generation recently, the limited long-term service stability is the main obstruct for their applications. In this work, we have prepared two kinds of Ti-based alloys (Ti83.7Al10.7Si5.6and Ti74Ni26) as the diffusion barrier layer of CoSb3-based TE joints by the spark plasma sintering method and have systematically investigated their interfacial behaviors during the aging process. The performances of contact resistivity and mechanical strength for Ti74Ni26/Yb0.4Co3.8Fe0.2Sb12TE joints are good before aging treatment but gradually deteriorate during the aging process, which should be ascribed to the phase-transition-induced negative thermal expansion in Ti–Ni alloys. On the other hand, Ti83.7Al10.7Si5.6/Yb0.4Co3.8Fe0.2Sb12TE joints show both low contact resistivity (<10 μΩ·cm2) and high mechanical strength (>20 MPa) before and after 16-day aging at 500 °C, which is originated from the matching of the coefficient of thermal expansion (CTE) and the formation of network structures in Ti–Al–Si alloys. We have also prepared an eight-couple TE module of p-Ge0.9Sb0.1TeB0.01/n-Yb0.4Co3.8Fe0.2Sb12and have measured its corresponding device performance. Our work has demonstrated that the matched CTE and network structures in the Ti–Al–Si alloy are key to obtain high-performance CoSb3-based TE joints for long-term service.

The isothermal section at 500 °C of the phase diagram of the Dy–Fe–V ternary system was investigated by X-ray powder diffraction, electron probe microanalysis and metallo-graphic microanalysis. The ternary system consists of nine single-phase regions, sixteen two-phase regions and eight three-phase regions. The existence of five binary compounds were confirmed and only one ternary compound, DyFe10V2, was found in this isothermal section. The solubilities of Dy in the solid solutions of V in Fe, Fe in V and FeV are about 2.6 at.%., 3.5 at.% and 5.5 at.%., respectively.

For decades, the V2VI3compounds, specifically p-type Bi2–xSbxTe3and n-type Bi2Te3–xSex, have remained the cornerstone of commercial thermoelectric solid-state cooling and power generation near room temperature. However, a long-standing problem in V2VI3thermoelectrics is that n-type Bi2Te3–xSexis inferior in performance to p-type Bi2–xSbxTe3near room temperature, restricting the device efficiency. In this work, we developed high-performance n-type Bi2–xSbxTe3, a composition long thought to only make good p-type thermoelectrics, to replace the mainstream n-type Bi2Te3–xSex. The success arises from the synergy of the following mechanisms: (i) the donorlike effect, which produces excessive conduction electrons in Bi2Te3, is compensated by the antisite defects regulated by Sb alloying; (ii) the conduction band degeneracy increases from 2 for Bi2Te3and Bi2Te3–xSexto 6 for Bi2–xSbxTe3, favoring high Seebeck coefficients; and (iii) the larger mass fluctuation yet smaller electronegativity difference and smaller atomic radius difference between Bi and Sb effectively suppresses the lattice thermal conductivity and retains decent carrier mobility. A state-of-the-art zTof 1.0 near room temperature was attained in hot deformed Bi1.5Sb0.5Te3, which is higher than those for most known n-type thermoelectric materials, including commercial Bi2Te3–xSexingots and the popular Mg3Sb2. Technically, building both the n-leg and p-leg of a thermoelectric module using similar chemical compositions has key advantages in the mechanical strength and the durability of devices. These results attested to the promise of n-type Bi2–xSbxTe3as a replacement of the mainstream n-type Bi2Te3–xSexnear room temperature.

To build high-performance thermoelectric (TE) devices for power generation, a suitable diffusion-barrier layer between the electrodes and the TE materials in a TE device is generally required for achieving good interfacial connection with high reliability, high mechanical strength but low electrical and thermal contact resistivities. GeTe-based materials have attracted great attention recently due to their high TE performance in the mid-temperature range, but studies on their TE devices are still limited. Here, we selected the Al66Si34alloy as a diffusion barrier for GeTe-based TE legs based on the matching test of the coefficient of thermal expansion. The good connection between Al66Si34and Ge0.9Sb0.1TeB0.01is realized by the interfacial reaction, where the randomly distributed Al2Te3and Ge precipitates are formed at the interface of the joint. The as-prepared interfacial electrical contact resistivity can be as low as 20.7 μΩ·cm2and only slightly increases to 26.1 μΩ·cm2after 16 days of aging at 500 °C. Moreover, the shear strength of the joints can be as high as 26.6 MPa and unexpectedly increases to 41.7 MPa after 16 days of aging. The thickness of the reaction layer tends to be stabilized after 8 days of aging and nearly does not change after further aging to 16 days, which may be ascribed to the drag effect from Si and the secondary Ge phases. These results demonstrate the great potential of the Al–Si alloy as a diffusion barrier for GeTe-based TE devices with high performance.

Two-dimensional germanium sulfide (GeS), an analogue of phosphorene, has attracted broad attention owing to its excellent environmental stabilities, fascinating electronic and optical properties, and applications in various nanodevices. In spite of the current achievements on 2D GeS, the report of ultrathin few-layer GeS nanosheets within 5 nm is still lacking. Here in this contribution, we have achieved preparation of ultrathin few-layer GeS nanosheets with thicknesses of 1.3 ± 0.1 nm [approximately three layers (∼3L)], 3.2 ± 0.2 nm (∼6L), and 4.2 ± 0.3 nm (∼8L) via a typical liquid-phase exfoliation (LPE) method. Based on various experimental characterizations and first-principles calculations, the layer-dependent electronic, transport, and optical properties are investigated. For the few-layer GeS nanosheets, enhanced light absorption in the UV–vis region and superior photoresponse behavior with increasing layer number is observed, while for the thin films above 10 nm, the properties degenerate to the bulk feature. In addition, the as-prepared ultrathin nanosheets manifest great potential in the applications of photoelectrochemical (PEC)-type photodetectors, exhibiting excellent and stable periodic photoresponse behavior under the radiation of white light. The ∼8L GeS-based photodetector exhibits superior performance than the thinner GeS nanosheets (<4 nm), even better as compared to the bulk or film (above 10 nm) counterparts in terms of higher photoresponsivity along with remarkable photodetection performance in the UV–vis region. This work not only provides direct and solid evidence of the layer-number evolutionary band structure, mobility, and optical properties of ultrathin 2D GeS nanosheets but also promotes the foreseeable applications of 2D GeS as energy-related photoelectric devices.

The Bi2Te3-based alloys have been commercialized for the applications of energy harvesting and refrigeration for decades. However, the commercial Bi2Te3-based alloys produced by the zone-melting (ZM) method usually show poor mechanical strength and crack problems as well as the sluggish figure of merit ZT, especially for the less-progressed n-type samples. In this work, we have simultaneously enhanced the thermoelectric and mechanical performance of the one-step spark plasma sintering (SPS)-derived n-type Bi2Te2.7Se0.3alloys just by doping a small amount of superconducting material MgB2where Mg and B atoms can play significant roles in carrier density optimization and hardness enhancement. Besides the optimization of carrier density, the MgB2doping can also increase the carrier mobility but decrease the lattice and bipolar thermal conductivity, leading to a peak ZT of 0.96 at 325 K and an average ZT of 0.88 within 300–500 K in the 0.5% MgB2-doped Bi2Te2.7Se0.3(BTSMB) alloys. The peak ZT and average ZT of our optimized BTSMB samples are comparable and higher than those of the state-of-the-art commercial ZM ingot. Moreover, the optimized BTSMB sample also exhibits almost 70% enhancement in hardness compared with the ZM ingot. Our results demonstrate the great potential of the MgB2doping strategy for mass production of SPS-derived Bi2Te3-based alloys in one-step sintering.

Given afferent functions, sensory nerves have recently been found to exert efferent effects and directly alter organ physiology. Additionally, several studies have highlighted the indirect but crucial role of sensory nerves in the regulation of the physiological function of osteoclasts. Nonetheless, evidence regarding the direct sensory nerve efferent influence on osteoclasts is lacking. In the current study, we found that high levels of efferent signals were transported directly from the sensory nerves into osteoclasts. Furthermore, sensory hypersensitivity significantly increased osteoclastic bone resorption, and sensory neurons (SNs) directly promoted osteoclastogenesis in an in vitro coculture system. Moreover, we screened a novel neuropeptide, Cyp40, using an isobaric tag for relative and absolute quantitation (iTRAQ). We observed that Cyp40 is the efferent signal from sensory nerves, and it plays a critical role in osteoclastogenesis via the aryl hydrocarbon receptor (AhR)-Ras/Raf-p-Erk-NFATc1 pathway. These findings revealed a novel mechanism regarding the influence of sensory nerves on bone regulation, i.e., a direct promoting effect on osteoclastogenesis by the secretion of Cyp40. Therefore, inhibiting Cyp40 could serve as a strategy to improve bone quality in osteoporosis and promote bone repair after bone injury.

Materials with low lattice thermal conductivity (κlat) are crucial for the applications of thermal insulation and thermoelectric (TE) energy conversion. Stacking fault (SF)-induced phonon scattering within interfaces has been put forward theoretically by Klemens in 1950s. However, unlike other traditional defects such as point defects, grain boundaries, and dislocations, the role of SF for reducing κlatremains poorly understood and is yet to be revealed experimentally. The layered Bi2Te3with a van der Waals gap shows different stacking structures than the nonlayered GeTe, which is used to introduce SFs into the GeTe-based alloys in this work. On the basis of the experimental and theoretical modeling results, this paper reveals the significant contribution of SF phonon scattering for minimizing the κlat. Besides the achieved extremely low κlat(∼0.39 W m–1K–1at 573 K), optimized carrier density and band convergence are also realized in the GeTe-based alloys upon Bi2Te3alloying, leading to a significant high TE figure of merit ZT> 2 at 773 K and an averaged ZT> 1.4 within 300–773 K. This SF engineering strategy provides a different avenue to reduce the κlatfor enhancing the performance of thermal insulation and TE materials.

The energy density of present lithium-ion capacitors (LICs) is greatly hindered by the limited specific capacities of porous carbon electrodes. Herein, we report the development of a nonaqueous LIC system by integrating two reversible electrode processes, that is, anion doping/undoping in a core–shell structured polypyrrole/carbon nanotube (Ppy@CNT) composite cathode and Li+intercalation/deintercalation in a Fe3O4@carbon (C) anode. The hybrid Ppy@CNT is utilized as a promising pseudocapacitive cathode for nonaqueous LIC applications. The Ppy provides high pseudocapacitance via the doping/undoping reaction with PF6–anions. Meanwhile, the CNT backbone significantly enhances the electrical conductivity. The as-developed composite delivers noteworthy capacities with exceptional stability (98.7 mA h g–1at 0.1 A g–1and retains 89.7% after cycling at 3 A g–1for 1000 times in Li-half cell), which outperforms state-of-art porous carbon cathodes in present LICs. Furthermore, when paired with Fe3O4@C anodes, the as-developed LICs demonstrate a superior energy density of 101.0 W h kg–1at 2709 W kg–1and still maintain 70 W h kg–1at an increased power density of 17 186 W kg–1. The findings of this work provides new knowledge on the cathode materials for LICs.

ZrNiSn-based half-Heusler (HH) alloys are considered very promising thermoelectric (TE) materials at intermediate and high temperatures due to their favorable intrinsic electrical properties, but they are also limited by their inherent high thermal conductivities. Numerous works have focused on reducing their thermal conductivities, especially their lattice thermal conductivities. A multielement (Ti, Hf, Nb, V, and Sb) and multisite alloying strategy for simultaneously improving the electrical properties and greatly reducing the lattice thermal conductivity of ZrNiSn-based HH TE materials is reported in this work. The continuous enhancement in structural disorder is the main factor in dramatically suppressing the lattice thermal conductivity of the materials. The use of suitable dopants also optimizes the electrical properties of the material, which is also an indispensable aspect in achieving high ZTvalues. As a consequence, a lowest lattice thermal conductivity κl= 0.99 W/(m K) and a highest ZT∼ 1.2 were obtained for Zr0.95M0.05Ni1.04Sn0.99Sb0.01(M = Ti0.25Hf0.25V0.25Nb0.25) refined by a ball-milling process. The calculated conversion efficiency (η) of the same sample from room temperature to 873 K was close to 12%. In addition, compared with that used in other studies, the amount of Hf used in this study was greatly reduced, which means a reduction in cost. All of the findings in this study make the commercialization of ZrNiSn-based TE materials more competitive.

Keratin 17 (K17) is strongly expressed in psoriatic lesions but not healthy skin, and plays a crucial role in disease pathogenesis. The mechanism of aberrant K17 expression in psoriasis has not been fully elucidated. MicroRNAs are short, single-stranded, noncoding RNAs that play important roles in regulating gene expression. Psoriasis exhibits a specific microRNA expression profile distinct from that of healthy skin. In this study, we showed that miR-486-3p was markedly reduced in psoriatic epidermis and negatively correlated with the psoriasis area and severity index score. Its expression repressed K17 protein expression and decreased proliferation in a keratinocyte cell line overexpressing K17 (LV K17) compared with controls. Our data indicated that miR-486-3p was regulated by a transforming growth factor-β (TGFβ)/SMAD pathway and possibly mediated the downregulation of K17 protein in TGFβ-treated keratinocytes. Finally, the decreased expression of TGFβ receptor I in psoriatic epidermis inactivated the TGFβ/SMAD pathway, leading to K17 overexpression and cell proliferation. Collectively, our findings demonstrated that a TGFβ/SMAD/miR-486-3p signaling axis in keratinocytes regulated K17 expression and cell proliferation. We conclude that the loss of miR-486-3p in psoriatic epidermis leads to K17 protein overexpression and contributes to the pathogenesis of psoriasis. Overexpression of miR-486-3p may therefore be a therapeutic option for psoriasis.

High symmetry favors high power factor by virtue of the balanced Seebeck coefficient and carrier mobility, nonetheless, the role of crystal symmetry in enhancing the material’s thermoelectric performance is abstruse. Here, we employ the interplay between crystal symmetry and native point defects towards high zTof IV-VI semiconductor GeSe, which is scarce in thermoelectric study. Pristine orthorhombic GeSe has a low zT~ 0.05 due to the high formation energy of Ge vacancy and thus the low carrier concentration (~ 1016cm−3). Alloying GeSe with MnCdTe2stabilizes higher-symmetry rhombohedral structure at ambient conditions, thereby effectively lowering the formation energy of Ge vacancy and raising the carrier concentration by four orders of magnitude. Meanwhile, compared to orthorhombic GeSe, the rhombohedral Ge1-yBiySe(MnCdTe2)xown higher valley degeneracy and smaller band effective mass, rendering the decent Seebeck coefficient and larger carrier mobility, respectively. Moreover, the generated multiscale microstructures in rhombohedral Ge0.96Bi0.04Se(MnCdTe2)0.10, including atomic-scale native Ge vacancies and substitution point defects, nanoscale domain structures, and micron-sized secondary phases effectively depress the lattice thermal conductivity. As a result, a state-of-the-art zT~ 1.0 at 723 K is achieved in Ge0.96Bi0.04Se(MnCdTe2)0.10. These results attest to the efficacy of the interplay between crystal symmetry and native point defects towards high performance GeSe-based and other thermoelectric materials.

Cubic-spinel Ag1-xCuxIn5S8is promising as it is a kind of In–S-based thermoelectric material using eco-friendly elements like In, Cu and S. Here, we develop a melting method to synthesize single-phase Ag1-xCuxIn5S8alloys using metal sulfides as precursors, and we also comprehensively study their thermoelectric properties, chemical bonding, electronic and phonon structures, and defect chemistry. Owing to the complex crystal structures, weak chemical bonding, and “rattling-like” phonon modes, the Ag1-xCuxIn5S8alloys show low lattice thermal conductivity of ∼0.63–0.72 Wm−1K−1 at 873 K. The optimal figure of merit (ZT) of the n-type Ag1-xCuxIn5S8can reach ∼0.31 at 873 K, which is higher than the theoretical prediction. The diamond-like crystal structures also enable them to have good mechanical properties, with a hardness of ∼3.95 GPa, comparable to those thermoelectric materials with the highest mechanical strength. Our understanding of the “rattling-like” phonon modes and defect chemistry in AgIn5S8can also guide the further development of the more promising p-type AgIn5S8and other advanced cubic-spinel thermoelectric materials.

In thermoelectrics, the material’s performance stems from a delicate tradeoff between atomic order and disorder. Generally, dopants and thus atomic disorder are indispensable for optimizing the carrier concentration and scatter short-wavelength heat-carrying phonons. However, the strong disorder has been perceived as detrimental to the semiconductor’s electrical conductivity owing to the deteriorated carrier mobility. Here, we report the sustainable role of strong atomic disorder in suppressing the detrimental phase transition and enhancing the thermoelectric performance in GeTe. We found that AgSnSe2and Sb co-alloying eliminates the unfavorable phase transition due to the high configurational entropy and achieve the cubic Ge1–x–ySbyTe1–x(AgSnSe2)xsolid solutions with cationic and anionic site disorder. Though AgSnSe2substitution drives the carrier mean free path toward the Ioffe–Regel limit and minimizes the carrier mobility, the increased carrier concentration could render a decent electrical conductivity, affording enough phase room for further performance optimization. Given the lowermost carrier mean free path, further Sb alloying on Ge sites was implemented to progressively optimize the carrier concentration and enhance the density-of-state effective mass, thereby substantially enhancing the Seebeck coefficient. In addition, the high density of nanoscale strain clusters induced by strong atomic disorders significantly restrains the lattice thermal conductivity. As a result, a state-of-the-art zT≈ 1.54 at 773 K was attained in cubic Ge0.58Sb0.22Te0.8(AgSnSe2)0.2. These results demonstrate that the strong atomic disorder at the high entropy scale is a previously underheeded but promising approach in thermoelectric material research, especially for the numerous low carrier mobility materials.

The ability to create advanced cathode nanomaterials with greatly enhanced energy density for rechargeable Zn batteries remains a grand challenge. Herein, we craft bimetallic NiCo2S4-xwith tunable sulfur deficiency as effective cathode materials for Zn batteries with large capacity, high rate capability and outstanding cycle stability. Notably, the sulfur vacancies can be judiciously tailored to increase the electrical conductivity and number of active sites for electrochemical reaction. The resulting sulfur-deficient NiCo2S4-xnanotube arrays on carbon cloth (denoted sd-NiCo2S4-x@CC) present high capacities of 298.3 and 175.7 mAh g−1at 0.5 and 5 A g−1, respectively, which outperform the CC-support-free NiCo2S4-xnanotube and NiCo2O4nanowire counterparts. Mechanistic study reveals the partial dissolution of S elements in sd-NiCo2S4-x@CC electrodes, which has not been observed in sulfide-based Zn batteries. The redox reaction of sd-NiCo2S4-x@CC involves the formation of NiS4-x-2yOH, CoSyOH, and CoSyO during charging and S doped NiO and CoO during discharging. The residual S-doping effect in bimetallic electrode materials is key to sustain high reactivity and cycle stability. Furthermore, a flexible solid-state sd-NiCo2S4-x@CC//Zn@CC battery is assembled using sodium polyacrylate hydrogel electrolyte, displaying an unprecedented cyclic durability of 84.7% after 1500 cycles at 5 A g−1. As such, the deficiency (e.g., S, O, P, etc.) tailoring represents a robust strategy to yield high performance electrode materials for energy storage devices.

In recent years, due to the shortage of fossil fuel energy and the deterioration of the environment, increasing attention has been paid to the utilization of geothermal power, especially medium–low-temperature geothermal energy, which occupies a large proportion of hot water resources. This paper summarizes the research status of Bi2Te3-, MgAgSb-, Mg3Sb2-, Mg2(Si,Sn,Ge)- Ag2Se-and AbSbTe2-based near-room-temperature thermoelectric (TE) materials and summarizes the research results of TE technology used in geothermal water power generation. TE power generation technology can directly transform heat into electricity by TE devices, with the advantages of environmental protection, low carbon emissions, no mechanical moving parts, high thermal and mechanical stability and no noise. The improving performance of the investigated TE materials suggests that TE power generation technology is the key technology for clean geothermal power generation. Future research directions include further improving the TE performance, reducing costs and enhancing the research and design of TE devices and power generators.

This article employs electrochemical deposition to prepare thermoelectric film materials to achieve a miniaturized radioisotope thermoelectric generator (RTG). First, the optimal composition and material properties are obtained by optimizing the deposition potential and the concentration of the electrolyte. The n‐type material can reach the highest thermoelectric power factor of 812.34 μW m−1K−2at a deposition potential of 0 V vs Ag/AgCl, and its composition is Bi1.92Te3.08. The highest power factor of 137.18 μW m−1K−2of the p‐type material is obtained when the ratio of the concentration of SbO+to Bi3+ions in the electrolyte solution is set to 6 with the deposition potential of −0.12 V vs Ag/AgCl. The composition is Bi0.68Sb1.24Te3.08. Then, a principle fan‐shaped RTG (FRTG) with an overall size of 11 mm (height) × 33.8 mm (diameter) is manufactured and tested. The FRTG generates an open‐circuit voltage of 170.21 mV, a maximum output power of 247.55 nW, and a temperature difference of 57.8 K at 1.5 W heat source. Compared with the RTG prepared by mechanical cutting in previous research, the FRTG exhibits a volume that is reduced by 12.45 times and a voltage that is increased by 60.71%. This study uses an electrodeposition method to prepare a thin‐film thermoelectric material to achieve miniaturization of a radioisotope thermoelectric generator (RTG). The authors propose a fan‐shaped RTG that is expected to be used to power space electronic devices in the future. This method can be used for the miniaturization of other power supplies.

Indexed powder diffraction patterns and related crystallographic data are reported for ErNiSb, which is not represented in the X-ray Powder Diffraction File. The compound ErNiSb is cubic [space group F43m, Z=4, a=6.2693(1) ?]. The R=0.067 indicates that experimental intensities agree well with the calculated patterns.

Polythiophene /multi-wall carbon nanotubes (MWNT) composites were prepared by ball-mailing. The morphology and internal structure of the composites were evaluated by field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD). Their thermoelectric properties, i.e., the electrical conductivity, the Seebeck coefficient and the thermal conductivity, were investigated in detail. The remarkably increased electrical conductivity, the slightly increased Seebeck coefficient and the relatively insensitive thermal conductivity with increasing MWNT content led to an obvious enhancement in the thermoelectric figure of merit. The results showed that the MWNT were uniformly dispersed in the polymer matrix, and that increasing the electrical conductivity is the key factor for enhancing the thermoelectric figure of merit. This study suggested a simple way to improve the thermoelectric performances of conducting polymers.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

For Abstract see ChemInform Abstract in Full Text.