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Mg3Sb2-based thermoelectrics show great promise for next-generation thermoelectric power generators and coolers owing to their excellent figure of merit (zT) and earth-abundant composition elements. However, the complexity of the defect microstructure hinders the advancement of high performance. Here, the defect microstructure is modified via In doping and prolonged sintering time to realize the reduced structural disorder and microstructural evolution, synergistically optimizing electron and phonon transport via a delocalization effect. As a result, an excellent carrier mobility of ~174 cm2 V−1 s−1 and an ultralow κ l a t of ~0.42 W m−1 K−1 are realized in this system, leading to an ultrahigh zT of ~2.0 at 723 K. The corresponding single-leg module demonstrates a high conversion efficiency of ~12.6% with a 425 K temperature difference, and the two-pair module of Mg3Sb2/MgAgSb displays ~7.1% conversion efficiency with a 276 K temperature difference. This work paves a pathway to improve the thermoelectric performance of Mg3Sb2-based materials, and represents a significant step forward for the practical application of Mg3Sb2-based devices. The authors modify complex defect microstructure in Mg3Sb2-based thermoelectrics to reduce structural disorder and promote microstructural evolution, synergistically optimizing electron and phonon transport via a delocalization effect for high performance. [ABSTRACT FROM AUTHOR]

Developing thermoelectric (TE) performance is impeded by the compromise of TE parameters, resulting in inadequate conversion efficiency of heat to electricity. Herein, this work reports that Mo is a particularly effective additive in Mg3Sb2‐based alloys with significantly improved electronic transport via grain‐boundary engineering and band‐structure regulation synergy. In addition, phonon transport is simultaneously suppressed by employing multiple effects, lattice imperfection scattering, reduced phonon group velocity, and enhanced atomic disorder, leading to a minimum κlat = 0.52 W m−1 K−1 at 723 K. As a result, an outstanding ZT peak of ≈1.84 at 723 K and ZTav = 1.34 within 323–723 K are achieved in Mg3Sb2‐based alloys, and the corresponding fabricated single‐leg TE module shows an exceptionally high conversion efficiency of ≈12% under a hot‐side temperature of 450 °C. These results demonstrate the great potential for advancing mid‐temperature heat harvesting in Mg3Sb2‐based materials. [ABSTRACT FROM AUTHOR]

Organic/inorganic hybrid synthesis methods are effective for fabricating flexible thermoelectric (TE) films and devices. In the present study, a flexible Mg0.99Cu0.01Ag0.99Sb0.97/graphene/PEDOT:PSS (MCAS/G/P) TE film was prepared on a polytetrafluoroethylene (PTFE) substrate. A physical process was developed to resolve the cracking problem during the hybrid process. In this hybrid structure, MCAS particles constitute a matrix, while a conductive network formed by graphene and PEDOT:PSS reduces the interfacial contact resistance between MCAS particles, thereby facilitating carrier transport and in turn enhancing the electrical properties of the hybrid films. The graphene content in the MCAS/x wt% G/P hybrid system was optimized by evaluating the TE properties, which reveals that the optimum content of graphene is 40 wt%. Furthermore, the influence of a hybrid mass fraction on both the TE properties and mechanical flexibility of the ternary hybrid film was systematically investigated. As a result, a maximum power factor (PF) of 31 μW m−1 K−2 was obtained at a 93.8 wt% powder ratio. However, mechanical bending tests revealed that a maximum PF of 16 μW m−1 K−2 was obtained for the flexible MCAS/G/P film loaded with 88.3 wt% MCAS/G. The hybrid synthesis method proposed in this work may pave the way for a design strategy in the fabrication of novel material-based flexible TE films and spur the emerging application of new hybrid flexible materials in energy harvesting. [ABSTRACT FROM AUTHOR]

Much effort has recently been put into developing high-performance low-temperature thermoelectric materials for waste-heat recovery and thermoelectric cooling. Here, we report an unusual enhancement of low-temperature figure of merit (ZT) in quenched p-type GeTe-based alloys. The average ZT within the low-temperature range (300–473 K) for the as-synthesized quenched GeTe-based alloys can reach 1.1, which is even better than that of the state-of-the-art commercial Bi0.5Sb1.5Te3 ingots. Moreover, the as-synthesized samples also show superior thermoelectric performance in the mid-temperature range, demonstrating great promise for thermoelectric applications in a broad temperature range. The Ge-vacancy arrays can serve as high-speed channels with low effective mass for carrier transport but obstacles for phonon transport, resulting in increased carrier mobility and reduced lattice thermal conductivity simultaneously for high ZT in the as-synthesized quenched GeTe-based alloys. These findings provide an intriguing way to enhance ZT and to develop low-temperature thermoelectric materials beyond Bi2Te3-based alloys. [ABSTRACT FROM AUTHOR]

Thermoelectric cooling materials based on Bi2Te3 have a long history of unsurpassed performance near room temperature. Recently, research into price‐competitive Mg3(Bi, Sb)2‐based materials are focused on replacing traditional cooling materials. Here, the thermoelectric properties of Mg3.2Bi1.998−xSbxTe0.002Cu0.005 (x = 0.0, 0.1, 0.2, 0.3, 0.4, and 0.5) polycrystalline compounds are investigated. In all temperature regions, electrical resistivity and Seebeck coefficient are increased with Sb concentration. The electronic transport properties of Sb‐alloyed compounds are maximized by synergistically combined band engineering approaches such as band structure change caused by lattice strain, increased electronic density of states, and chemical potential shift, leading to exceptionally high‐power factor values of over 3.0 mW m−1 K−2 at room temperature. Furthermore, with increasing Sb content, thermal conductivity values are systematically reduced due to the promotion of alloy scattering of phonons and suppression of the bipolar contribution. Consequently, these multiple approaches significantly enhance thermoelectric performance, resulting in an enhancement of thermoelectric figure‐of‐merit zT above 1.1 at 348–423 K. Additionally, a zTavg of 1.1 is recorded at 300–450 K, making it an unrivaled value among the reported n‐type Mg3Bi2‐based thermoelectric materials. Overall, this work demonstrates that Mg3Bi2‐based materials are more promising for thermoelectric cooling applications compared to Bi2Te3‐based materials. [ABSTRACT FROM AUTHOR]

Background: High interleukin-6 levels correlate with diseases like cancer, autoimmune disorders, and infections. IL-6 receptor inhibitors (IL-6Ri), used for rheumatoid arthritis and COVID-19, may have wider uses. We apply drug-target Mendelian Randomization (MR) to study IL-6Ri's effects., Method: To simulate the effects of genetically blocking the IL-6R, we selected single nucleotide polymorphisms (SNPs) within or near the IL6R gene that show significant genome-wide associations with C-reactive protein. Using rheumatoid arthritis and COVID-19 as positive controls, our primary research outcomes included the risk of asthma, asthmatic pneumonia, cor pulmonale, non-small cell lung cancer, small cell lung cancer, Parkinson's disease, Alzheimer's disease, ulcerative colitis, Crohn's disease, systemic lupus erythematosus, type 1 diabetes, and type 2 diabetes. The Inverse Variance Weighted (IVW) method served as our principal analytical approach, with the hypotheses of MR being evaluated through sensitivity and colocalization analyses. Additionally, we conducted Bayesian Mendelian Randomization analyses to minimize confounding and reverse causation biases to the greatest extent possible., Results: IL-6 inhibitors significantly reduced the risk of idiopathic pulmonary fibrosis (OR= 0.278, 95% [CI], 0.138-0.558; P <0.001), Parkinson's disease (OR = 0.354, 95% CI, 0.215-0.582; P <0.001), and positively influenced the causal relationship with Type 2 diabetes (OR = 0.759, 95% CI, 0.637-0.905; P = 0.002). However, these inhibitors increased the risk for asthma (OR = 1.327, 95% CI, 1.118-1.576; P = 0.001) and asthmatic pneumonia (OR = 1.823, 95% CI, 1.246-2.666; P = 0.002). The causal effect estimates obtained via the BWMR method are consistent with those based on the IVW approach. Similarly, sIL-6R also exerts a significant influence on these diseases.Diseases such as Alzheimer's disease, Crohn's disease, pulmonary heart disease, systemic lupus erythematosus, Type 1 diabetes, Non-small cell lung cancer and ulcerative colitis showed non-significant associations (p > 0.05) and were excluded from further analysis. Similarly, Small cell lung cancer were excluded due to inconsistent results. Notably, the colocalization evidence for asthmatic pneumonia (coloc.abf-PPH4 = 0.811) robustly supports its association with CRP. The colocalization evidence for Parkinson's disease (coloc.abf-PPH4 = 0.725) moderately supports its association with CRP., Conclusion: IL-6Ri may represent a promising therapeutic avenue for idiopathic pulmonary fibrosis, Parkinson's disease, and Type 2 diabetes., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Fu, Wang and Cai.)

To better understand the role of stationary sources during the evolution of haze, we investigated sulfate formation characteristics at different stages of four haze events in Beijing, China. The mass fraction of sulfate in PM 2.5 increased while that of nitrate declined slightly during the worsening process of most haze events, consistent with higher ratios of SO 4 2- /NO 3 - on haze days (0.50 on average) than those on clean days (0.32 on average). Further calculations indicated that sulfate had a higher mass growth rate than nitrate during the haze-worsening process, probably due to regional transport of sulfate from heavy industrial areas accompanied by increased sulfate secondary transformation during polluted periods. We quantitatively evaluated the contribution of the S(IV) + NO 2 reaction (pH-dependent) in sulfate formation during the haze evolution. The production rate (P S(IV)+NO2 ) of the S(IV) + NO 2 pathway ranged from 1.97 × 10 -4 to 5.91 (mean: 0.39) μg·m -3 ·h -1 . Its proportion to sulfate total heterogeneous production rate (P S(IV)+NO2 /P het ) was generally correlated positively with PM 2.5 concentrations, indicating the relative importance of this pathway on haze days. Due to the mutual restriction between aerosol pH and aerosol liquid water content (ALWC) during haze evolution, the relative contribution of the S(IV) + NO 2 pathway to sulfate heterogeneous formation was generally limited to 40%., (Copyright © 2019 Elsevier B.V. All rights reserved.)