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Microorganisms, especially viruses, cause disease in both humans and animals. Environmental chemical pollutants including microplastics, pesticides, antibiotics sand air pollutants arisen from human activities affect both animal and human health. This review assesses the impact of chemical and biological contaminants (virus and bacteria) on viruses including its life cycle, survival, mutations, loads and titers, shedding, transmission, infection, re-assortment, interference, abundance, viral transfer between cells, and the susceptibility of the host to viruses. It summarizes the sources of environmental contaminants, interactions between contaminants and viruses, and methods used to mitigate such interactions. Overall, this review provides a perspective of environmentally co-occurring contaminants on animal viruses that would be useful for future research on virus-animal-human-ecosystem harmony studies to safeguard human and animal health. [Display omitted] • Environmental contaminants influence animal viral infections. • Chemical contaminants including microplastics, pesticides, antibiotics, air pollutants, affect viral infections. • Biological contaminants including viruses and bacteria, affect animal viral infections. • Review would be useful for future virus-animal-human-ecosystem interaction research. [ABSTRACT FROM AUTHOR]

Lanthanum telluride (La 3- x Te 4) is one of the important candidates of thermoelectric (TE) materials working at high temperatures over 1000 K. However, the thermal stability and oxidation resistance of the TE materials become the crucial issue when they are working at so high temperatures. In this report, it is found that, although La 3- x Te 4 exhibits excellent thermal stability up to 1200 K under inert atmosphere, the existence of oxygen even in very low partial pressure causes serious oxidation and performance degradation at a temperature over 700 K. By introducing metallic nickel particles into La 2.74 Te 4 matrix forming La 2.74 Te 4 /Ni composites, the oxidation rate is greatly reduced both in air and low oxygen partial pressure (Po 2 = 10−3 MPa). The dense La 2 NiO 4 /Ni 2 Te 3 O 8 /NiO oxide composite layer formed during oxidation is in charge of "blocking" the diffusion of oxygen. Dispersing Ni particles gives indistinct influence on the thermoelectric properties leading to a good dimensionless thermoelectric figure of merit as 1.0 at 1273 K in the La 2.74 Te 4 /10 vol.% Ni composite. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: Ab-initio calculations of the resonant modes and frequencies for a number of possible fillers in p-type RFe3CoSb12 and RFe4Sb12 were carried out. The results indicate that, although the exact values of fillers’ resonant frequencies in p-type skutterudites are somewhat different from those in n-type Co-based skutterudites, the Einstein-like resonant modes of the fillers are similar to those in n-type materials. Experimentally, several pairs of the fillers were selected and double-filled p-type skutterudite compounds RxMy Fe3CoSb12 (R, M = Ba, Ce, Nd, and Yb) were successfully synthesized. The reduction in the lattice thermal conductivity was realized by extending the range of resonant frequencies. As a result, enhanced ZT values above unity were achieved in these double-filled p-type skutterudites. [Copyright &y& Elsevier]

Thermoelectric (TE) fibers are more suitable than films for portable or wearable devices. Herein, 2–3 nm thick poly (3,4‐ethylenedioxythiophene): poly (styrenesulfonate) (PEDOT:PSS) layer‐coated tellurium nanowires (PC‐Te NWs) are in situ prepared by a hydrothermal method. Then a series of PEDOT: PSS/PC‐Te NWs composite fibers are prepared by wet spinning and post‐treatment. The nanolayer prevents the agglomeration of the Te NWs and makes the NWs and PEDOT:PSS matrix have good compatibility, which results in the PC‐Te NWs content to a high value of 70 wt% and the fibers still with flexibility. The high aspect ratio of the PC‐Te NWs and the stress from the inner wall of the needle during spinning make the NWs ordered align along the composite fiber. Due to the large content and orientational arrangement of the PC‐Te NWs, as well as effective post‐treatment, an optimized composite fiber shows a power factor of 385.4 µW m−1 K−2 at 300 K, which is ≈4.9 times as high as the highest value of previously reported PEDOT:PSS/Te NWs‐based composite fibers. In addition, the composite fiber has good flexibility. The flexible TE generators assembled have excellent output performance. This work provides an effective strategy for the preparation of high‐performance flexible TE composite fibers. [ABSTRACT FROM AUTHOR]

La3Te4-based rare-earth telluride is a kind of n-type high-temperature thermoelectric (TE) material with an operational temperature of up to 1273 K, which is a promising candidate for thermoelectric generators. In this work, the Sm substitution in La3−xSmxTe4/Ni composites is reported. The electrical transport property of La3−xSmxTe4 is modified by reducing carrier concentration due to the substitution of Sm2+ for La3+. The electric thermal conductivity decreases by 90% due to carrier concentration reduction, which mainly contributes to a reduction in total thermal conductivity. Lattice thermal conductivity also decreases by point-defect scattering by Sm doping. Meanwhile, based on our previous study, compositing nickel improves the thermal stability of the La3 − xSmxTe4 matrix. Finally, combined with carrier concentration optimization and the decreased thermal conductivity, a maximum zT of 1.1 at 1273 K and an average zTave value of 0.8 over 600 K–1273 K were achieved in La2.315Sm0.685Te4/10 vol.% Ni composite, which is among the highest TE performance reported in La3Te4 compounds. [ABSTRACT FROM AUTHOR]

α-MgAgSb is taken as the p-type leg material for recently focused Mg-based thermoelectric devices because of the high thermoelectric performance near room temperature. However, the thermoelectric performance of α-MgAgSb is inhibited by the existence of the Ag-rich second phase. The ordinary methods like carrier concentration optimization and minimizing lattice thermal conductivity were nearly invalid because of the extremely low doping level for heteroatoms and intrinsically low lattice thermal conductivity. The crystal structure of α-MgAgSb can be viewed as Ag atom filled in half distorted hexahedron in the distorted rock salt skeleton formed by the Mg–Sb sublattice. In this work, by replacing the smaller Mg in the sublattice with Pb, the volume of the distorted hexahedron is effectively expanded to accommodate Ag atoms and then lead to the re-dissolution of Ag-rich second phase in the matrix. In addition, as Ag is the main source of low-frequency phonons, the enhanced lattice anharmonicity by Pb doping leads to stronger scattering of phonons in the distorted hexahedron and results in 20% reduction of lattice thermal conductivity in the temperature range of 300–500 K. Finally, the figure of merit zT is enhanced by ∼40% in the whole temperature range, demonstrating that lattice management is a promising method for the optimization of α-MgAgSb materials. [ABSTRACT FROM AUTHOR]

Polycrystalline samples of the title thermoelectric solid solution of title (x = 0-0.5, δ = 0.02-0.05) are prepared by melting and annealing stoichiometric amounts of the elements (graphite crucible in evacuated silica tubes, 1. [ABSTRACT FROM AUTHOR]

At present, the weak thermoelectric and mechanical performance of zone‐melting bismuth telluride alloys cannot support the further improvement of cooling and processing performance of semiconductor refrigeration devices. Here, MnO2 is added into high‐strength Bi0.4Sb1.6Te3 prepared by ball milling method to optimize its thermoelectric transport properties. Via in situ reaction, Sb2O3 nano‐precipitates are formed in the matrix, which also leads to the surplus of Te element. As results, the donor‐like effect is suppressed, thereby increasing carrier concentration and power factor. Besides, volatilization of Te‐rich phases during sintering leaves plentiful nanopores, which together with Sb2O3 nano‐precipitates significantly decrease the lattice thermal conductivity. Eventually, the maximum ZT reaches 1.43 at 75 °C for the Bi0.4Sb1.6Te3+0.01MnO2 sample. On this basis, a 31‐pairs module made of the material and commercial n‐type BiTeSe produces large temperature differences (ΔT) of 70.1, 80.8, and 89.4 K at the hot‐side temperature (Th) of 300, 325, and 350 K respectively, which are highly competitive. The maximum coefficient of performance of 8.6 and cooling capacity of 7 W are achieved when Th is set as 325 K. This excellent progress will promote the further development of bismuth telluride refrigeration modules. [ABSTRACT FROM AUTHOR]

CuInTe2 is synthesized from the elements (evacuated silica tube, 900 °C, 12 h; annealing at 650 °C) and characterized by powder XRD and thermoelectric measurements. [ABSTRACT FROM AUTHOR]

Thermoelectric transient pulse cooling can break through the limitations of thermoelectric material properties and achieve cooling performance beyond steady-state, which has great potential in active thermal management of high-power electronic devices. However, traditional control strategy for thermoelectric cooler (TEC) under steady cooling modes severely limits the widespread application of pulse cooling. This work focused on the key issue of precise temperature control under ultra-high thermal shock, and developed a novel control strategy composed of PID control, transient pulse control, and feed-forward control. By involving the thermoelectric transient pulse cooling effect, TEC can bear much high thermal load, and feed-forward control can further improve the temperature stability. As a result, the new strategy can bear extreme pulse thermal load as high as 4.59 times of the maximum cooling capacity of the TEC in steady-state within width of 20 ms, and the temperature fluctuation can be suppressed to 0.5 K from 7.58 K by using traditional control strategy based on maximum steady-state cooling capacity. This work demonstrates that the control strategy based on transient pulse cooling can greatly improve the capacity and response speed of thermoelectric cooling, providing important reference for precise temperature control of high-power electronic devices. • A novel control strategy was developed for the transient cooling mode in TEC. • Control strategy based on transient pulse effect realizes higher cooling capacity. • Feed-forward control can improve the temperature control precision. [ABSTRACT FROM AUTHOR]

Summary: Waste heat recovery helps reduce energy consumption, decreases carbon emissions, and enhances sustainable energy development. In China, energy‐intensive industries dominate the industrial sector and have significant potential for waste heat recovery. We propose a novel waste heat recovery system assisted by a heat pipe and thermoelectric generator (TEG) namely, heat pipe TEG (HPTEG)，to simultaneously recover waste heat and achieve electricity generation. Moreover, the HPTEG provides a good approach to bridging the mismatch between energy supply and demand. Based on the technical reserve on high‐temperature heat pipe manufacturing and TEG device integration, a laboratory‐scale HPTEG prototype was established to investigate the coupling performances of the heat pipes and TEGs. Static energy conversion and passive thermal transport were achieved with the assistance of skutterudite TEGs and potassium heat pipes. Based on the HPTEG prototype, the heat transfer and the thermoelectric conversion performances were investigated. Potassium heat pipes exhibited excellent heat transfer performance with 95% thermal efficiency. The isothermality of such a heat pipe was excellent, and the heat pipe temperature gradient was within 15°C. The TEG's thermoelectric conversion efficiency of 7.5% and HPTEG's prototype system thermoelectric conversion efficiency of 6.2% were achieved. When the TEG hot surface temperature reached 625°C, the maximum electrical output power of the TEG peaked at 183.2 W, and the open‐circuit voltage reached 42.2 V. The high performances of the HPTEG prototype demonstrated the potential of the HPTEG for use in engineering applications. [ABSTRACT FROM AUTHOR]

In‐grain dislocation‐induced lattice strain fluctuations are recently revealed as an effective avenue for minimizing the lattice thermal conductivity. This effect could be integratable with electronic enhancements such as by band convergence, for a great advancement in thermoelectric performance. This motivates the current work to focus on the thermoelectric enhancements of p‐type PbTe alloys, where monotelluride‐alloying and Na‐doping are used for a simultaneous manipulation on both dislocation and band structures. As confirmed by synchrotron X‐ray diffractions and Raman measurements, the resultant dense in‐grain dislocations induce lattice strain fluctuations for broadening the phonon dispersion, leading to an exceptionally low lattice thermal conductivity of ≈0. 4 W m‐K−1. Band structure calculations reveal the convergence of valence bands due to monotelluride‐alloying. Eventually, the integration of both electronic and thermal improvements lead to a realization of an extraordinary figure of merit zT of ≈2.5 in Na0.03Eu0.03Cd0.03Pb0.91Te alloy at 850 K. [ABSTRACT FROM AUTHOR]

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. Likewise, co-doping (Mg, Sb) in GeTe successfully tunes the carrier concentration to the optimal range and effectively suppresses the lattice thermal conductivity. A peak zT of 1.84 at 800 K and an average zT of 1.2 in 300–800 K have been achieved in Ge0.85Mg0.05Sb0.1Te. Finally, a Ni/Ti/Ge0.85Mg0.05Sb0.1Te thermoelectric uni-leg is fabricated and tested, showing quite good service stability even after 450 thermal cycles between 473 K and 800 K. This study will accelerate the application of GeTe-based compounds for power generation in the mid-temperature range. [ABSTRACT FROM AUTHOR]

• Influence of Peltier heat on test accuracy of Transient Electro-thermal is studied. • High accuracy test for thermal conductivity of TE films can be achieved in TPET. • The heat transfer model to measure double-layers film in TPET is established. Accurate and rapid measurement of thermal conductivity of thin films has been a challenge so far in the field of thermoelectric (TE) materials and devices. Herein, we proposed to use a transient photo-electro-thermal (TPET) technique to measure the thermal conductivity of TE thin-films with convenience. Combining theoretical and experimental methods, we found that the TPET technique using laser beam heating can significantly reduce the influence of Peltier effect and thus achieve high test accuracy. The measurement uncertainty of TPET technique for TE films can be depressed below 10%. Furthermore, this method is not only applicable for free-standing thin film, but also for thin film deposited on as-known substrates. Finally, thermal conductivity of several films including p -type Bi 0.5 Sb 1.5 Te 3 , n -type Ag 2 Se, and n -type Bi 2 Te 3 deposited on PI film at different temperature are accurately measured, which demonstrates the wide applicability of TPET technique on semiconductor films. [ABSTRACT FROM AUTHOR]

High performance flexible thermoelectric thin films are desired for power generation of flexible thermoelectric device. Thermoelectric performance of (Sb,Bi) 2 Te 3 films are determined by the Te content in the matrix as anti-site defect dominates the carrier concentration. By controlling the Te target co-sputtering power, annealing temperature and time, not only the film in-plane orientation is enhanced, the carrier concentration is also effectively controlled in this work. Through a systematically investigation of Te content dependence of the thermoelectric performance, the carrier concentration and orientation is optimized through tuning Te content, and a high power factor of ∼32 μ W/cm-K2 for Sb 2 Te 3 film, ∼36 μ W/cm-K2 for Bi 0.5 Sb 1.5 Te 3 film is realized in in-plane orientation. Besides, The thermal conductivity along in-plane direction is determined by photon-electro-thermal (TPET) technique, and the final zT values are ∼0.49 for Sb 2 Te 3 , and ∼0.58 for Bi 0.5 Sb 1.5 Te 3 films at room temperature, respectively. • Enhanced in-plane orientation by Te co-sputter. • Systematically Te content control and Carrier concentration optimization. • In-plane thermal conductivity measurement by photon-electro-thermal (TPET) technique. • High power factor ∼32 μ W/cm-K2 for Sb 2 Te 3 film, ∼36 μ W/cm-K2 for Bi 0.5 Sb 1.5 Te 3 film. [ABSTRACT FROM AUTHOR]

A novel hybrid film is designed and prepared by in situ growth of ZnO nanoribbons in the interstices of Zn 2 SnO 4 nanoplates network on the compacted woven metal wires through a simple process. The ZnO nanoribbons present in the ZnO/Zn 2 SnO 4 composite film can enhance light harvesting, accelerate electron transport and induce a negative shift in the flat-band potential. Benefiting from its advantageous structure and composition, the ZnO/Zn 2 SnO 4 film can be applied in many fields. For the flexible dye-sensitized solar cells (FDSSCs) employing optimized ZnO/Zn 2 SnO 4 as a photoanode, the conversion efficiency reaches 2.41% corresponding to ∼36.2% improvement relative to the Zn 2 SnO 4 nanoplates-based FDSSCs. Moreover, ZnO/Zn 2 SnO 4 -based FDSSC shows relatively good mechanical stability and long-term stability, retaining 95.1% and 93.3% of its initial efficiency after ten consecutive bending tests and after 15 days under sunlight, respectively; Additionally, the immobilized ZnO/Zn 2 SnO 4 on the metal wires exhibits 96.8% photocatalytic degradation efficiency against an organic dye under UV light, and the photocatalytic performance can be restored almost completely by a simple chemical treatment. More importantly, the in situ growth technique demonstrated in this work can be adopted to fabricate other composite oxides on flexible substrates with high curvature surfaces for additional practical applications in flexible devices. [ABSTRACT FROM AUTHOR]

For enhanced solar energy application, double-layered nitrogen-doped Zn 2 SnO 4 film consisting of bottom nanosheets and top nanoparticles is designed and synthesized on flexible woven metal wires. The effects of doping concentration of nitrogen element (N) and the amount of coating nanoparticles on electronic, optical properties and stability are investigated in detail by various testing techniques. The results show that in the double-layered structure, the nanosheets array can provide direct transport pathways for photoinduced electrons, while the nanoparticles can provide high surface area. On the other hand, doped N element is conducive not only to the absorption of visible light due to narrowed band gap, but also to suppression of charge recombination. With the optimized double-layered N-doped Zn 2 SnO 4 as photoanodes of flexible dye-sensitized solar cells, the corresponding photoelectric conversion efficiency is 2.302% compared to 1.332% and 1.826% in case of pure Zn 2 SnO 4 nanosheets and N-doped Zn 2 SnO 4 nanosheets; The double-layered N-doped Zn 2 SnO 4 is also determined to be high-performance immobilized photocatalyst with a better recyclability for the photodegradation of organic pollutant under sunlight irradiation; More importantly, the preparation methods is also applicable to fabricate other composite oxides on wire-shaped substrate for more practical applications in flexible devices. [ABSTRACT FROM AUTHOR]

• Flexible thermoelectric devices are in situ fabricated from printed Cu patterns. • Rationally designed nanosheets arrays result in strong phonons scattering. • Optimal ZT values of 0.5 for Cu 2 Se and 0.7 for Ag 2 Se were achieved. • The device exhibits outstanding power density of 13.4 W m−2 (△T = 40 K) Flexible thermoelectric (TE) devices have great potential in wearable electronics, but there is great challenge to realize robust TE device with high performance via feasible integration process. Herein, based on precisely printed copper patterns, a flexible p Cu 2 Se- n Ag 2 Se TE device is initially realized by in situ ion exchange reaction. The as-prepared Cu 2 Se and Ag 2 Se films possess typical hierarchical defects including atomic scale vacancies, the nanosheet fragments and microscale porous structure, which could significantly scatter phonons in wide frequency range. Accordingly, ultra-low thermal conductivity (Cu 2 Se: 0.13 W m−1 K−1; Ag 2 Se: 0.15 W m−1 K−1) and optimal ZTs (Cu 2 Se: 0.5; Ag 2 Se: 0.7) are achieved. Meanwhile, the as-fabricated p Cu 2 Se- n Ag 2 Se TE device exhibits an excellent power density of 13.4 W m−2 at a temperature gradient of 40 K, which is among the highest values of printed in-plane film devices. Furthermore, the good adhesion between TE films and porous PI substrate endowed excellent flexibility and stability of p Cu 2 Se- n Ag 2 Se devices. [ABSTRACT FROM AUTHOR]

• The power density is higher than other thin-film thermoelectric generator. • Substrate with unique structure resulted in increase of both output voltage and the maximum output power. • A comprehensive 3D simulation with variable parameter was developed. [Display omitted] Thermoelectric generators can be used as energy harvesting for power supply in Internet of Thing sensors. Here, material properties and geometry parameters were investigated to improve the annular thin-film thermoelectric generator (ATTEG) output performances. The as-deposited and annealed n-type Bi 2 Te 2.7 Se 0.3 and p-type Bi 0.5 Sb 1.5 Te 3 were deposited by radio frequency magnetron sputtering which resulted in higher Seebeck coefficient and electrical conductivity of annealed thin films. The temperature distributions and output performances in ATTEG were calculated using numerical simulation to identify the geometry parameters. The results showed that thinner substrate with higher output performances, larger legs number with higher output voltage, and a peak point in the maximum output power was observed for the effect of the angle ratio of p-type leg to n-type leg with optimal value of 1. We fabricated ATTEGs with different TE legs to identify the machining accuracy, and the ATTEG with 12 legs resulted in output voltage of 27.7 mV, the maximum output power of 169.0 nW and power density of 127.39 n W ∕ cm 2 at a temperature difference of 23 K. Hollowing and nicking on substrate were proposed as further improvement, and resulted in increasement of 6.6% in output voltage and 13.6% in the maximum output power. [ABSTRACT FROM AUTHOR]

Previous reports about the thermal conductivities of VO showed various temperature dependences across metal-insulator transition (MIT) temperature. In this work, polycrystalline VO samples were fabricated by spark plasma sintering of VO powder. Temperature dependences of their thermal conductivities were investigated using laser flash technique, and the thermal conductivity showed a significant decrease trend from metal-phase to insulator phase. Electrical transport properties were investigated to confirm both carrier and lattice contribution to the thermal conductivity. It is found that the lattice thermal conductivity decreased significantly across MIT point, which may be caused by soft phonon mode in metal phase of VO. [ABSTRACT FROM AUTHOR]

Abstract: p-type Sn-doped CoSb3-based skutterudite compounds have been prepared using melting–quenching–annealing method and spark plasma sintering technique. Sn atoms in our samples are completely soluted on Sb-site with a fixed charge state and non-magnetic feature, providing a better choice to ascertain the effect of element doping at the [Co4Sb12] framework on the electrical and thermal transport properties in p-type skutterudites. Doping Sn at the framework introduces additional ionized impurity scattering to affect the electron transport greatly. Similar electrical transport properties between Ce0.2Co4Sb11.2Sn0.8 and Co4Sb11Sn0.6Te0.4 suggest that Ce fillers contribute little to the valence band edge. Filling Ce into the voids and doping Sn at the framework introduce additional phonon resonant and point defect scattering mechanisms, thereby reducing lattice thermal conductivity remarkably. Moreover, our data suggest that combining these two effects is more effective to suppress lattice thermal conductivity through scattering broad range of phonons with different frequencies. [ABSTRACT FROM AUTHOR]

• Deposit composite with complex 3D hierarchical structure on the mesh by multiple EPD. • Stainless steel mesh-supported SnO 2 /Zn 2 SnO 4 can be used as varied flexible devices. • Provide a way to build material with 3D structure on flexible wire mesh. Three dimensional (3D) hierarchical micro/nanostructures are an interesting class of materials with various tunable physicochemical properties and have good application foreground in environmental protection. However, it is hard for the micrometer-sized material to directly grow on high curvature surface of metal wire mesh for assembling flexible devices. In this paper, the two SnO 2 /Zn 2 SnO 4 composites with different hierarchical morphologies prepared using solvothermal method were deposited onto stainless steel mesh by the multiple electrophoretic deposition, and used as photoanodes of flexible dye-sensitized solar cell (FDSSCs), flexible gas sensors to detect poisonous formaldehyde (HCHO) and immobilized photocatalysts for the degradation of two different types of organic dyes. Due to larger specific surface areas, the higher light harvesting efficiency and mesoporous property, the performances of the flexible devices based SnO 2 /Zn 2 SnO 4 microspheres consisting of nanoparticle-based nanosheets were superior to those based on SnO 2 /Zn 2 SnO 4 microspheres consisting of nanobelts. This work extends the development of SnO 2 /Zn 2 SnO 4 hierarchical micro/nanostructures on the flexible substrate and provides a strategy for constructing other 3D hierarchical material on the flexible wire mesh with the high curvature surface to enhance performance of corresponding flexible devices. [ABSTRACT FROM AUTHOR]