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Recently, defective three-quarter Heusler compounds MCo1.5Sn (M = Ti, Zr, and Hf) have been reported with interesting crystal structure differing from the traditional half-Heusler and full-Heusler compounds. These defective compounds are metallic ferromagnets, but the detailed correlation between magnetic and electrical transport properties is still unclear. In this study, we dope Cu in ZrCo1.5Sn to dilute the magnetic Co atoms with the purpose of clarifying how the magnetism influences the electrical transport properties in the defective three-quarter Heusler compounds. Significantly lowered ferromagnetic transition temperature and decreased saturated magnetic moment are observed in Cu-doped ZrCo1.5Sn due to the diluted Co atoms. Likewise, in the ferromagnetic phase, the dominant carrier scattering mechanism is changed from spin fluctuation scattering to magnetic impurity scattering. The doped Cu atoms introduce non-bonding states below the valence band maximum, resulting in the appearance of a narrow bandgap around 0.1 eV. Correspondingly, the electric transport behavior in the paramagnetic phase shows a semiconducting character with a negative temperature dependence of resistivity. This study provides further understanding to the correlation between magnetic properties and electrical transport properties in defective Heusler-based compounds. [ABSTRACT FROM AUTHOR]

Diamondlike compound Cu2SnS3 has attracted great attention recently due to its excellent thermoelectric performance and the features of being eco-friendly and low cost. However, the underlying mechanism for its good electrical transports under high carrier concentration range is still not clear. In this work, we synthesized a series of Cu2+xSn1−xS3 (x = 0–0.08) samples. These nonstoichiometric Cu2+xSn1−xS3 samples are polymorph simultaneously crystalizing in the monoclinic, tetragonal, and cubic structures. The characterization on the electrical transports and the analysis on the band structure reveal that the large density-of-states effective mass, high Seebeck coefficient, and high mobility under a high carrier concentration in the Cu2+xSn1−xS3 system are originated from the existence of multiple bands near the edge of the valence band. Likewise, the polymorphic structure has little influence on the electrical transports. A maximum power factor of 12.6 μW cm−1 K−2 at 700 K has been obtained for the nonstoichiometric Cu2.08Sn0.92S3. Combining the low lattice thermal conductivity of these samples, Cu2.08Sn0.92S3 shows a peak dimensionless figure of merit of 0.5 at 700 K. This work is helpful for guiding the future optimization of thermoelectric performance on Cu2SnS3. [ABSTRACT FROM AUTHOR]

Thermoelectric (TE) power generation is expected to be one of the most effective solutions to convert industrial exhaust heat to electricity for conserving fossil energy and reducing carbon emissions. However, its real application is obstructed decisively by the weakness of the service stability of state‐of‐the‐art TE materials at high temperatures in air. Refractory iron silicide (β‐FeSi2) used to be widely investigated as TE materials, but the low zT has restricted its practical application and even made it almost vanish from TE research in recent years. Here, guided by theoretical calculation, ultrahigh solubility of Ir on the Fe sites of β‐FeSi2 is successfully realized. Doping 16% Ir elicits multi‐valley electrical conduction and phonon‐electron scattering, doubling the previous zT record of β‐FeSi2 to ≈0.6 at 1000 K. The TE properties of the obtained β‐FeSi2 are practically unchanged after thermal aging in air at 1173 K. The new conceptual electrode‐less β‐FeSi2‐based refractory module demonstrates considerable power density and stable power generation when it is burned by a gas flame in air. These results mark a step toward developing practical TE power generation technology for the recovery of industrial waste heat. [ABSTRACT FROM AUTHOR]

Flexible thermoelectrics, including flexible thermoelectric materials and devices, can directly convert the heat from human body into useful electricity, providing a promising solution for uninterrupted power to wearables. In the past decade, flexible thermoelectrics has achieved notable progress. Various kinds of flexible thermoelectric materials have been developed and some of them have been fabricated into flexible thermoelectric devices, showing the ability to generate nW‐level or even μW‐level electricity. Herein, the basic design principles and typical configurations of flexible thermoelectric devices, as well as the requirements on thermoelectric materials to achieve high performance flexible thermoelectric devices, are first introduced. Then, the recent progress achieved in flexible thermoelectric devices based on organics materials, traditional inorganic materials, other organic/inorganic composites/hybrids, and plastic deformable inorganic semiconductors, respectively, are summarized. Finally, an outlook on the future development of flexible thermoelectrics is briefly given. This study sheds light on the further development of flexible thermoelectrics. [ABSTRACT FROM AUTHOR]

Intel software guard extensions (SGX) increase the security of applications by enabling them to be performed in a highly trusted space (called enclave). Most state-of-the-art attacks on SGX focus on either mining the software vulnerabilities in the enclave or speculating the secret data with side channels. In this study, we report our recent work on breaking SGX by inducing voltage-oriented hardware faults. The novelty and importance of this attack are that it is completely controlled by software and does not require any security vulnerability in the software. Our proposed attack, called VoltJockey, exploits a vulnerability in the implementation of dynamic voltage and frequency scaling (DVFS) that achieves energy saving by dynamically adjusting the processor’s operating voltage and thus clock frequency. However, if the operating voltage is lower than a certain critical level, the circuit’s timing constraint will fail and hardware fault would be created. We propose to deliberately trigger such voltage-oriented hardware faults by a loadable kernel module that can set the processor’s voltage through Intel’s undocumented model-specific register (MSR). We first utilize the module to furnish the processor with a transient low voltage with controlled timing to inject a temporal fault into the target location of the program running in the enclave. Then, we perform a differential fault attack on the outputs before and after the injection of faults. For demonstration, we successfully deploy the proposed attack to extract the key of an AES executed in the enclave and lead an SGX-protected RSA to output our specified result. [ABSTRACT FROM AUTHOR]

Cu‐Fe‐S‐based compounds gain the interest from thermoelectric community because all the consisting elements, Cu, Fe, and S, are non‐toxic and earth‐abundant. Comparing with CuFeS2 and Cu5FeS4, the investigation on Cu9Fe9S16 is very rare. In this work, a series of Cu9–xFe9+xS16 samples were fabricated by means of melting‐annealing process. Their phase composition, microstructure, electrical and thermal transport properties were systematically investigated. X‐ray measurement confirms that all samples are phase pure. Transmission electron microscopy characterization indicates that the fabricated Cu9Fe9S16 has a natural nanostructure. Cu9Fe9S16 shows semiconducting‐like electrical transport behavior and intrinsically low lattice thermal conductivity. Beyond the numerous boundaries between nanosized grains, the existence of low‐frequency optical phonons is also responsible for the intrinsically low lattice thermal conductivity. Doping Fe at the Cu‐sites in Cu9Fe9S16 significantly alters the electrical transport properties by introducing extra carriers. A peak dimensionless figure of merit zT value of 0.21 is obtained at 800 K for pure Cu9Fe9S16, which is comparable with that for CuFeS2. [ABSTRACT FROM AUTHOR]

Thermoelectric technology has attracted great attention due to its ability to recover and convert waste heat into readily available electric energy. Among the various candidate materials, liquid‐like compounds have received tremendous research interest on account of their intrinsically ultralow lattice thermal conductivity, tunable electrical properties, and high thermoelectric performance. Despite their complex phase transitions and diverse crystal structures, liquid‐like materials have two independent sublattices in common: one rigid sublattice formed by immobile ions for the free transport of electrons and one liquid‐like sublattice consisting of highly mobile ions to interrupt the thermal transports. This review first outlines the common structural features of liquid‐like thermoelectrics, along with their unusual electron and phonon transport behaviors that well satisfy the concept of "phonon‐liquid electron‐crystal." Next, some commonly adopted strategies for further improving their thermoelectric performance are highlighted. The main progress achieved in the typical liquid‐like TE materials is then summarized, with an emphasis on their diverse crystal structures, common characteristics, and unique transport properties. The recent understandings on the stability issue of liquid‐like TE materials are also introduced. Finally, an outlook is given for the liquid‐like materials with the aim to boost further development in this exciting scientific subfield. [ABSTRACT FROM AUTHOR]

Liquid‐like thermoelectric (TE) materials have the advantages of ultrahigh performance, low cost, and environment friendly, but their stability is greatly limited by the possible Cu/Ag deposition under a large current and/or temperature gradient. The pratical application based on liquid‐like TE materials requires both a high TE figure of merit (zT) for high energy conversion efficiency and large critical voltage for good stability, but they are very difficult to be simultaneously achieved in one material. In this work, both the zT and critical voltage are simultaneously optimized in Cu2Se via tailoring chemical compositions at multiple atomic positions, i.e., introducing Cu deficiency at the Cu‐sites to lower Cu ion chemical potential and alloying sulfur at the Se‐sites to reduce carrier concentrations. A maximum zT of 2.0 at 1000 K has been successfully achieved for Cu1.96Se0.8S0.2, about a 30% improvement over that for Cu2Se. More importantly, Cu1.96Se0.8S0.2 demonstrates a much higher critical voltage than Cu2Se, yielding a greatly enhanced service stability under the conditions with/without a temperature gradient. An Ni/Mo/Cu1.96Se0.8S0.2 TE unileg is successfully fabricated with a stable power output even after 400 thermal cycles between 473 and 873 K. This study greatly accelerates the real application of Cu2Se‐based liquid‐like materials. [ABSTRACT FROM AUTHOR]

TiCoSb-based half-Heusler compounds have been prepared and their thermoelectric properties are studied. By isoelectronic alloying on the Ti site with Zr, although both the thermal conductivity and electrical conductivity are suppressed, the Seebeck coefficient is improved remarkably with a highest value of -420 μV/K for Ti0.5Zr0.5CoSb at 600 K, which provides a larger space to optimize the thermoelectric performance. To further improve the performance of the TiCoSb-based isoelectronic alloy, doping Ni on the Co site was explored. It is found that small amount of Ni doping results in a great increase in the electrical conductivity, still with a relative large Seebeck coefficient. Ti0.6Hf0.4Co0.87Ni0.13Sb sample exhibits a peak power factor of 23.4 μW/cm K2, which is the highest value for n-type TiCoSb-based half-Heusler compounds reported so far. As a result, a maximum dimensionless figure of merit of 0.70 has been achieved at 900 K for Ti0.6Hf0.4Co0.87Ni0.13Sb. [ABSTRACT FROM AUTHOR]

Copper (Cu)‐based thermoelectric (TE) materials have attracted great attention from both scientific and industrial societies, but for a long time, their real applications are greatly limited by the lack of high‐performance n‐type Cu‐based TE materials. Most recently, the novel n‐type Cu‐based TE material, CuIn5Se8, has been discovered to show a record‐high TE figure‐of‐merit (zT) to match the state‐of‐the‐art p‐type Cu‐based TE materials. However, the physical origin of such high zT is still unclear due to its complex phase compositions and crystal structures. In this work, it is revealed that the excellent TE performance is mainly contributed by the intrinsically ultralow lattice thermal conductivity originating from the unique all‐scale hierarchical architecture. It covers the ranges from atomic‐scale cation disorder in the tetragonal CuIn5Se8 phase and nanoscale diversified stacking units and stacking sequences in the hexagonal CuIn5Se8 phase, to mesoscale grain boundaries between the tetragonal phase and hexagonal phase. Doping Br at the Se‐sites can largely tune the electrical transports of CuIn5Se8 while maintaining the ultralow lattice thermal conductivity, leading to high zT reaching the optimal value predicted by the single parabolic model. This work will guide the investigation of n‐type Cu‐based TE materials in the future. [ABSTRACT FROM AUTHOR]

Metallic barrier layer is a key component in thermoelectric (TE) devices, but it is rarely investigated for the recently discovered inorganic ductile TE materials. In this work, we demonstrate that tungsten (W) is the excellent metallic barrier layer for Ag2S1−xSex ductile thermoelectric materials. The phase composition, microstructure, adhesive strength, and interfacial contact resistivity (ρC) of the W/Ag2S1−xSex joint have been systematically investigated. The sputtered W film has high adhesive strength and little interdiffusion/reaction with Ag2S1−xSex. The ρC decreases with increasing the Se content, which can be understood by the Thermionic-field Emission model. This work would guide the development of high-performance flexible TE devices based on ductile TE materials. [ABSTRACT FROM AUTHOR]

Abstract Soil microorganisms play an essential role in the redistribution of soil aggregate sizes due to the microenvironmental changes, but little is known about the changes in microbial communities (especially fungi) and their activities within different microenvironments due to agronomic managements. Here, we examined the influence of fertilization (inorganic and inorganic plus organic amendments) on soil aggregate distribution and the microbial communities within aggregates at the site of a long-term fertilization experiment. Significant impacts on soil aggregate distribution and distinct changes in fungal and bacterial communities in soil aggregates due to fertilization were observed, with the fungal community exhibiting more marked changes compared with the bacterial community. Soil carbon and nitrogen contents in aggregates were the most closely related to changes in microbial communities associated with soil aggregates. The changes of microbial taxa abundance in aggregates were generally accompanied by the redistributions of these taxa among all size aggregates, showing the preference for specific ecological niches for these taxa under fertilizations. Both applications of nitrogen alone (N) and inorganic plus organic amendment (NPKM) contributed to mega-aggregate formation. N treatment caused the low total fungal counts in mega-aggregates and carbon depletion, whereas it increased the abundance of N 2 O-producing fungi in both mega- and macro-aggregates, denitrifying bacteria in micro-aggregates and nitrifying bacteria in macro-aggregates. In contrast, NPKM treatment mitigated/prevented the sharp shifts of the abundance of these microbes mentioned above with nitrogen fertilization, and increased the ectomycorrhizal fungi abundance in all soil fractions as well as carbon accumulation in soil. Our results suggest that the responses of soil bacteria and fungi to fertilizations are modified by their ecological niches, which responses are responsible for the variation of ecosystem services. Highlights • Fertilizations changed distinctly fungal vs. bacterial community in soil aggregates. • Fertilizations caused shifts between enrichment and depletion of taxa in aggregates. • NPKM could reverse the microbial communities in aggregate under N application alone. • Soil C and N stores in aggregates closely affected microbial communities. [ABSTRACT FROM AUTHOR]

Control-flow integrity (CFI) plays a very important role in defending against code reuse attacks by protecting the control flows of programs from being hijacked. However, previous CFI methods suffer from performance overheads, cost, or security issues. In this paper, we propose a new CFI based on a lightweight encryption architecture with advanced encryption standard (LEA-AES) to address the challenges above. The LEA exploits AES to encrypt and decrypt return addresses and instructions at indirect jump destinations, which protects function calls and indirect jumps from being reused by return-oriented programming (ROP) and jump-oriented programming (JOP) attacks. For ROP, the encryption and decryption of return addresses are performed when the call and ret instructions are executing; for JOP, the encryption of instructions are performed when programs are loading into memory and the decryption of instructions are performed right before they are executing. The LEA-AES does not need to revise instruction sets of CPU and its security is also guaranteed by the encryption mechanism in addition to its high performance. Experimental results showed that the run-time and loading time overheads of LEA-AES are both less than 4% and the memory overhead is 0.62%. [ABSTRACT FROM AUTHOR]

Abstract: 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. In this work, it is revealed that n‐type AgInSe2 diamond‐like compound has intrinsically high thermoelectric performance with a figure of merit (zT) of 1.1 at 900 K, comparable to the best p‐type diamond‐like thermoelectric materials reported before. Such high zT is mainly due to the ultralow lattice thermal conductivity, which is fundamentally limited by the low‐frequency Ag‐Se “cluster vibrations,” as confirmed by ab initio lattice dynamic calculations. Doping Cd at Ag sites significantly improves the thermoelectric performance in the low and medium temperature ranges. By using such high‐performance n‐type AgInSe2‐based compounds, the diamond‐like thermoelectric module has been fabricated for the first time. An output power of 0.06 W under a temperature difference of 520 K between the two ends of the module is obtained. This work opens a new window for the applications using the diamond‐like thermoelectric materials. [ABSTRACT FROM AUTHOR]

We report a ternary argyrodite-type Ag9GaSe6 compound as a promising thermoelectric material in a moderate temperature range. Due to high carrier mobility and ultralow lattice thermal conductivity, a maximum ZT of 1.1 was obtained with stoichiometric Ag9GaSe6 at 800 K. Via introducing slight Se-deficiency to optimize the carrier concentration, the maximum ZT is further enhanced to 1.3. [ABSTRACT FROM AUTHOR]

Mode converters play a key role in the mode division multiplexing, which is an emerging technology to enlarge the information transmission capacity. The footprint and the performance of the mode converters are essential for the compact and energy-efficient integrated photonics. We numerically and experimentally demonstrate an on-chip multimode-interferometer-based mode converter, between the one-order mode and the fundamental mode, using metamaterial structures for phase shift and crosstalk suppression, and significantly reduce the footprint. The fabricated device has a high conversion efficiency of 79% and a broad 3 dB bandwidth of >50 nm, with an ultra-small footprint of only 2.4 × 8.9 μ m 2 . [ABSTRACT FROM AUTHOR]

Minute amounts of Fe/Mn are selected to be doped into CeyCo4Sb12 filled skutterudites to slightly compensate for electrons donated by the fillers. As a direct result, the Ce filling fractions are enhanced from 0.11 to 0.16. The carrier concentrations are improved by a factor of more than two times to approach the optimal values, leading to greatly improved power factors. Meanwhile, the lattice thermal conductivity is expectedly suppressed by the increased Ce fillers in the voids of skutterudites. Consequently, a maximum ZT of 1.3 at 850 K is obtained, which is comparable to that in the best single-filled skutterudites. [ABSTRACT FROM AUTHOR]

Abstract: Filling two or multiple atoms into the cages of a skutterudite crystal is a successful way to enhance the thermoelectric figure of merit in n-type partially filled skutterudites. Here we use La–Yb double filling to improve the thermoelectric performance of p-type skutterudites Yb x La y Fe2.7Co1.3Sb12 (x + y = 0.85, x = 0, 0.09, 0.17, 0.25, 0.34, 0.42, 0.85). The samples are synthesized by directly melting the raw materials followed by a long time annealing process. X-ray diffraction measurement confirms the skutterudite structure of the samples. By increasing the filling fraction of Yb, the lattice thermal conductivity is gradually depressed and reaches the lowest value of 0.9 W m−1 K−1 at high temperatures. At the same time, the Seebeck coefficient decreases while the electrical conductivity increases. The maximum power factor around 27 μW cm−1 K−2 for samples Yb0.17La0.68Fe2.7Co1.3Sb12 and Yb0.25La0.60Fe2.7Co1.3Sb12 is achieved at 600 K and 700 K, respectively. Sample Yb0.25La0.60Fe2.7Co1.3Sb12 has the maximum thermoelectric figure of merit 0.99 at 700 K, which is among the highest values among p-type filled skutterudites. [Copyright &y& Elsevier]

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]

The recently discovered ductile/plastic inorganic semiconductors pave a new avenue toward flexible thermoelectrics. However, the power factors of current ductile/plastic inorganic semiconductors are usually low (below 5 µW cm−1 K−2) as compared with classic brittle inorganic thermoelectric materials, which greatly limit the electrical output power for flexible thermoelectrics. Here, large plasticity and high power factor in bulk two‐dimensional van der Waals (2D vdW) single‐crystalline SnSe2 are reported. SnSe2 crystals exhibit large plastic strains at room temperature and they can be morphed into various shapes without cracking, which is well captured by the inherent large deformability factor. As a semiconductor, the electrical transport properties of SnSe2 can be readily tuned in a wide range by doping a tiny amount of halogen elements. A high power factor of 10.8 µW cm−1 K−2 at 375 K along the in‐plane direction is achieved in plastic single‐crystalline Br‐doped SnSe2, which is the highest value among the reported flexible inorganic and organic thermoelectric materials. Combining the good plasticity, excellent power factors, as well as low‐cost and nontoxic elements, bulk 2D vdW single‐crystalline SnSe2 shows great promise to achieve high power density for flexible thermoelectrics. [ABSTRACT FROM AUTHOR]

Temperature‐dependent photoluminescence (PL) properties of high quality cubic phase α‐CsPbI3 nanocrystals are investigated, and thermal transfer from free excitons to trapped excitons is observed. Free exciton recombination is the main origin of the high PL quantum yield (97%) at room temperature. Little change of PL peak energy is observed with decreasing temperature from 280 to 200 K, and it shifts from 1.84 to 1.81 eV in the region of 200 and 80 K. The PL peak intensity decreases with decreasing temperature first and then increases, and the minimum value is observed at 180 K. Two PL bands are obtained by Gaussian fittings in the PL spectra detected at different temperatures, and the high energy band is attributed to the emission of free excitons, while that for the low energy band is related to the transition of trapped excitons. The PL integrated intensity ratio of trapped exciton and free exciton transition increases from 0.18 to 2.10 with decreasing the temperature, which suggests that thermal transfer from free exciton to trapped exciton states leads to the dominant optical emission of trapped exciton recombination in the low temperature region. [ABSTRACT FROM AUTHOR]

• Na 2 S soaking process was proposed for non-vacuum prepared Cu 2 ZnSn(S,Se) 4 films. • Fine-grain layer can be eliminated by soaking precursor film in Na 2 S solution. • Short-circuit current of the solar cell was improved by the Na 2 S soaking. • 11.5% efficient Cu 2 ZnSn(S,Se) 4 solar cell was prepared. In this paper, we propose a Na 2 S soaking process (used as post-treatment process for the precursor films) for the non-vacuum prepared Cu 2 ZnSn(S,Se) 4 (CZTSSe) films. The CZTSSe film prepared without this process show triple-layer structure in which fine-grain layer and obvious layer-boundaries exist. By soaking the precursor film in Na 2 S aqueous solution with suitable concentration, the fine-grain layer in the triple-layer structure is substituted by a small-grain layer and the layer-boundaries become continuous. We find the quantum efficiencies of the solar cells in long wavelength region are improved by the Na 2 S soaking. Therefore, the short-circuit currents of the solar cells are significantly increased. By using the Na 2 S soaking process, CZTSSe solar cells with the best efficiency of 11.5% have been prepared. [ABSTRACT FROM AUTHOR]

Liquid‐like materials are one family of promising thermoelectric materials discovered in the past years due to their advantanges of ultrahigh thermoelectric figure of merit (zT), low cost, and environmental friendliness. However, their practial applications are greatly limited by the low service stability from the Cu/Ag metal deposition under large current and/or temperature gradient. Both high zT for high efficiency and large critical voltage for good stability are required for liquid‐like materials, but they are usually strongly correlated and hard to be tuned individually. Herein, based on the thermodynamic analysis, it is shown that such a correlation can be decoupled through doping immobile ions into the liquid‐like sublattice. Taking Cu2−δS as an example, doping immobile Fe ions in Cu1.90S scarcely degrades the initial large critical voltage, but significantly enhances the zT to 1.5 at 1000 K by tuning the carrier concentration to the optimal range. Combining the low‐cost and environmentally friendly features, these Fe‐doped Cu2−δS‐based compounds show great potential in civil applications. This study sheds light on the realization of both good stability and high performance for many other liquid‐like thermoelectric materials that have not been considered for real applications before. [ABSTRACT FROM AUTHOR]

The discovery of ductile Ag2(S, Se, Te) materials opens a new avenue toward high‐performance flexible/hetero‐shaped thermoelectrics. Specifically, the cubic‐structured materials are quite attractive by combining remarkable plasticity, decent thermoelectric figure of merit (zT), and no phase transition above room temperature. However, such materials are quite few and the understanding is inadequate on their mechanical and thermoelectric properties. Enlightened by the high‐entropy principles, a series of pseudo‐ternary Ag2S‐Ag2Se‐Ag2Te alloys is designed and comprehensive diagrams of composition‐structure‐plasticity‐zT are compiled. Subsequently, the compositional region for the cubic phase is outlined. As a high‐entropy example featuring with anion‐site alloying and disordered Ag ions, Ag2‐xS1/3Se1/3Te1/3 materials exhibit impressively large elongations of 60–97%, ultralow lattice thermal conductivities of ≈0.2 W m−1 K−1, and decent zT values of 0.45 at 300 K, 0.8 at 460 K. The materials can be readily rolled into thin foils, showing excellent flexibility. Finally, a six‐leg in‐plane device is fabricated, achieving an output voltage of 13.6 mV, a maximal power of 12.8 µW, and a power density of 14.3 W m−2 under the temperature difference of 30 K, much higher than the organic counterparts. This study largely enriches the members of cubic ductile inorganic materials for the applications in flexible and hetero‐shaped energy and electronic devices. [ABSTRACT FROM AUTHOR]

Deformable thermoelectrics have great potential in self‐powered flexible or hetero‐shaped electronics. The exceptional room‐temperature plasticity recently discovered in several inorganic semiconductors makes it possible to develop new thermoelectric (TE) materials with both high performance and intrinsic deformability. Nonetheless, all the known plastic or ductile TE materials are n‐type semiconductors. It is urgent to explore p‐type counterparts for device design and fabrication. In this study, the first p‐type plastic inorganic TE material is reported. Via alloying Cu in n‐type plastic Ag2S0.7Se0.3 to modulate the charged crystal defects, (Ag1−xCux)2S0.7Se0.3 (x = 0.7–0.8) can simultaneously realize good plasticity and p‐type conduction. Particularly, (Ag0.2Cu0.8)2S0.7Se0.3 with a hexagonal structure shows a maximum zT of 0.42 at 800 K. Via the introduction of Cu deficiencies, the good plasticity is well maintained while the maximum zT is greatly enhanced to 0.95 at 800 K, a record‐high value for plastic TE materials. This study is expected to accelerate the development of plastic TE semiconductors and full‐inorganic deformable TE devices for the application in hetero‐shaped power generators. [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]

In this work, we report the ternary Cu-based chalcogenide, Cu2TiTe3, as a promising thermoelectric material in middle-temperature range. The bonding interaction between Te p and Ti d states is observed in the Ti–Te octahedron, which drives the side bands up converging with Γ band, yielding a high valence band degeneracy of 5. A high electronic quality factor of 2.2 μW cm−1 K−2 and a decent power factor of 7.5 μW cm−1 K−2 at 300 K are achieved for Cu2TiTe3. Likewise, Cu2TiTe3 demonstrates low lattice thermal conductivity throughout the measured temperature range, which is attributed to the low frequency vibration related to the global motion of Ti–Te–Cu clusters. Finally, a maximum figure-of-merit of 0.38 was obtained for Cu2TiTe3 at 600 K. [ABSTRACT FROM AUTHOR]

Abstract Two heteronuclear clusters-based MOFs, CoLi(HL)·4DMA (HNU-23) and CoLi 2 (L)(DMF) 2 ·DMF·H 2 O (HNU-24) (H 4 L = 5- [bis(4-carboxybenzyl) amino] isophthalic acid) were successfully synthesized through a solvent-directed strategy. The luminescence sensing property investigations reveal that HNU-23 and HNU-24 exhibit turn-on luminescence towards the H+ concentration under strong acidic condition, and could be served as potential pH sensors. HNU-23 shows high linear H+ concentration response in the range of 0.02–0.2 M; HNU-24 exhibits similar linear response towards the H+ concentration from 0.1 to 0.2 M. The mechanism of this sensing behavior can be explained through disruption of the HNU-23 and HNU-24 structures under acidic condition to gradually release the fluorophore. Graphical abstract Two fascinated metal-organic frameworks constructed from tetranuclear and hexanuclear heterometallic clusters, respectively, are synthesized by a solvent-directed strategy, which can serve as efficient luminescent pH sensors under strong acidic condition. fx1 [ABSTRACT FROM AUTHOR]

Dyes are environmentally detrimental and prevalent pollutants in water. It is crucial to develop materials for water treatment with both adsorption/photocatalytic and antibacterial activity. In this work, bitter gourd-like Ag-loaded aramid nanofibers (ANFs@Ag) aerogel fibers were successfully prepared by a novel wet spinning process, in which the coupling of Ag nanoparticles (AgNPs) cluster on the fiber surface could be enhanced by using ANFs as a support carrier. The as-prepared ANFs@Ag aerogel fibers exhibit uniform porous structure with the specific surface area and pore volume being 235–298 m2 g−1 and 0.54–0.63 m3 g−1, respectively, and the photocatalytic activity of ANFs@Ag aerogel fibers could be achieved owing to the surface plasmon resonance (SPR) effect and interband electronic transition of the bitter gourd-like AgNPs layer. The ANFs@Ag aerogel fibers showed high removal efficiency of crystalline violet with up to 98.66% under xenon lamp irradiation due to the synergetic effect of adsorption and photocatalysis. Moreover, bacterial disk diffusion experiments revealed that the ANFs@Ag aerogel fibers have significant antibacterial performance against Escherichia coli and Staphylococcus aureus. In addition, the ANFs@Ag aerogel fibers exhibit superior thermal stability due to the loading of AgNPs. This work provides a new strategy for developing highly efficient porous ANFs–aerogel-based fiber composites, and the obtained bitter gourd-like ANFs@Ag composite aerogel fibers will have promising applications in the field of water purification. [ABSTRACT FROM AUTHOR]

Ge-Sb-Te compounds (GST), the well-known phase-change materials, are considered to be promising thermoelectric (TE) materials due to their decent thermoelectric performance. While Ge2Sb2Te5 and GeSb2Te4 have been extensively studied, the TE performance of GeSb4Te7 has not been well explored. Reducing the excessive carrier concentration is crucial to improving TE performance for GeSb4Te7. In this work, we synthesize a series of Se-alloyed GeSb4Te7 compounds and systematically investigate their structures and transport properties. Raman analysis reveals that Se alloying introduces a new vibrational mode of GeSe2, enhancing the interatomic interaction forces within the layers and leading to the reduction of carrier concentration. Additionally, Se alloying also increases the effective mass and thus improves the Seebeck coefficient of GeSb4Te7. The decrease in carrier concentration reduces the carrier thermal conductivity, depressing the total thermal conductivity. Finally, a maximum zT value of 0.77 and an average zT value of 0.48 (300–750 K) have been obtained in GeSb4Te5.5Se1.5. This work investigates the Raman vibration modes and the TE performance in Se-alloyed GeSb4Te7 sheddinglight on the performance optimization of other GST materials. [ABSTRACT FROM AUTHOR]

Soil microorganisms play an essential role in the redistribution of soil aggregate sizes due to the microenvironmental changes. Yet, little is known regarding how individual microbial taxa within different-sized aggregates respond to agronomic practice. This study integrated physical, chemical, and molecular techniques (i.e., high-throughput DNA sequencing and qPCR) to assess the influence of corn-tobacco rotation on the soil microbial community at the soil microenvironment scale, i.e., within mega- (>2 mm), macro- (0.25–2 mm) and micro-aggregate (<0.25 mm) fractions. The soil samples (0–20 cm) analyzed in this study originated from corn and tobacco, which were cultivated under three different fertilization regimes. The results demonstrate that corn-tobacco rotation substantially impacted the distribution of aggregate sizes, and the shift in soil microbial communities associated with soil aggregates was related to changes in soil total carbon (TC), the C/N ratio and pH. The indicator microbial taxa (i.e., those were sensitive to crop rotation) varied with aggregate size. When compared with tobacco soil, the corn soil showed higher relative abundances of probably more copiotrophic taxa across large-sized aggregates, also with more bacteria in mega-aggregates and more fungi in macro-aggregates. Changes in total microbial communities associated with mega- and macro-aggregates in response to crop rotation were driven mainly by alterations in bacterial and fungal communities, respectively. Overall, the results of this study demonstrate that soil aggregate size strongly affected the microbial community composition on agricultural fields, promoting the differential responses between bacteria and fungi to crop rotation in specific size of aggregates. [ABSTRACT FROM AUTHOR]

Recently, many novel superionic thermoelectric materials have been discovered along the concept of “phonon-liquid electron-crystal” (PLEC). Among them, Cu 2- x Se-based liquid-like materials are typical examples. In this study, a series of copper-deficient Cu 2- x Se (0.05 ≤ x ≤ 0.25) materials were synthesized and used to study the role of Cu vacancies on the electrical and thermal transport properties. The X-ray photoelectron spectroscopy (XPS) measurements suggest that the valence states of Cu and Se are independent on the Cu/Se atomic ratio. With increasing the content of Cu vacancies, the hole concentration is monotonously increased, leading to the improved electrical conductivity and reduced Seebeck coefficient. Based on the single parabolic band model analysis, it is found that changing the content of Cu vacancies does not obviously modify the material's electronic band structure and effective mass. Due to the presence of highly mobile Cu ions inside the crystal structure, the lattice thermal conductivities of all Cu 2- x Se (0.05 ≤ x ≤ 0.25) materials are very low with values around 0.39 W m −1 K −1 at 500 K. Because of the significantly reduced Seebeck coefficient and increased electronic thermal conductivity, the thermoelectric figure of merit zTs are decreased when increasing x from 0.05 to 0.25. At 750 K, a maximum zT of 0.46 is obtained in Cu 1.95 Se among all Cu 2- x Se (0.05 ≤ x ≤ 0.25) materials. [ABSTRACT FROM AUTHOR]

Background and purpose: The modified injection technique developed in Shandong Cancer Hospital and Institute, Shandong First Medical University and Shandong Academy of Medical Sciences has significantly improved the visualization rate of internal mammary sentinel lymph nodes (IMSLN), however there is still a gap between the visualization rate of IMSLN obtained by this technique and that of axillary sentinel lymph nodes (ASLN). The study aimed to further improve the IMSLN visualization rate and promote the widespread use of internal mammary sentinel lymph node biopsy (IM-SLNB) by optimizing the modified injection technique. Methods: A total of 159 patients with primary breast cancer were enrolled in a prospective group and divided into the optimized radiotracer technique group (group A, n=81) and the modified injection technique group (group B, n=78). In group A, 99mTc-sulfur colloid was injected averagely into parenchyma in the gland's three most abundant regions under ultrasound guidance (total radioactive intensity 1.0-1.3 mCi; 0.8-1.0 mL/point). In group B, 99mTc-sulfur colloid was injected averagely into the parenchyma of the breast at 6 and 12 points under ultrasound guidance (total radioactive intensity 1.0-1.3 mCi; 0.8-1.0 mL/point). Single photon emission computed tomography (SPECT)/computed tomography (CT) lymphoscintigraphy was performed preoperatively, and the sentinel lymph nodes were detected intraoperatively by γ probe. In this study, we evaluated the differences in IMSLN and ASLN visualization rates between the groups, and also analyzed the factors that may affect the IMSLN visualization rate. Results: There was no statistically significant difference in visualization rate of IM-SLN measured by preoperative SPECT/CT between the two groups (P=0.806). The intraoperative visualization rate of IM-SLN was significantly higher in group A than in group B (87.65% vs 70.51%, P=0.008). Analysis of subgroups showed that the intraoperative visualization rate of IMSLN was 92.31% and 83.33% (P=0.315) in group A patients aged ≤50 years and >50 years, respectively, and the intraoperative visualization rate of IMSLN was significantly higher in group B patients aged ≤50 years than in patients aged >50 years (81.58% vs 60.00%, P=0.037). The median in vitro radioactivity count of IMSLN was significantly higher in group A than in group B (160.50 vs 59.00, P=0.005). Conclusion: The optimized radiotracer technique can effectively increase the lymphatic drainage and uptake in the internal mammary region of the radiotracer, which can significantly improve the visualization rate of IM-SLN without affecting the visualization rate of ASLN, and is conducive to the promotion and application of IM-SLNB. [ABSTRACT FROM AUTHOR]

Background and purpose: Internal mammary lymph node irradiation (IMNI) improves survival in patients with internal mammary lymph node (IMLN) high-risk metastatic breast cancer. The purpose of this study was to study the advantages of internal mammary sentinel lymph node (IMLN) biopsy (IM-SLNB) for assessing prognosis and directing individualized IMNI. Methods: This study evaluated patients recruited in three prospective clinical trials (NCT01642511, NCT03541278, and NCT03024463) from November 2011 to December 2021, assessed for prognostic risk variables based on IMSLN metastatic status and prognosis between subgroups. In patients who received regional lymph node irradiation, the implementation status, survival benefit, and influence of IMNI on radiation-induced lung injury (RILI) were studied. The primary endpoint was disease-free survival (DFS), with overall survival (OS) and RILI as secondary endpoints. Results: The study enrolled 537 patients and had a 60-month median follow-up. Patients with IMSLN metastasis had a significantly worse 5-year DFS and OS (DFS: 95.1% vs 71.4%, OS: 99.1% vs 90.1%, both P<0.05), and IMSLN metastatic status was an independent risk factor for DFS and OS (both P<0.05). Adding IMNI did not improve DFS (P = 0.099) or OS (P = 0.486) in patients with negative IMSLN, while it did increase the risk of RILI (OR = 3.678, P<0.05). However, adding IMNI improved 5-year DFS (87.3% vs 52.5%, P = 0.040) for patients with positive IMSLN but had no effect on OS (P = 0.603). Conclusion: This study discovered that IMSLN metastatic status has significant prognostic importance. Patients with IMSLN metastasis who receive IMNI have significantly improved prognosis, and patients without IMSLN metastasis have a much lower risk of RILI by being exempt from IMNI without worse prognosis. [ABSTRACT FROM AUTHOR]

Purpose: Despite the poor prognosis of triple-negative breast cancer (TNBC), it has been demonstrated that neoadjuvant immunotherapy in combination with chemotherapy can improve the pathologic complete response (pCR) rate and/or long-term outcome of TNBC. However, there have been no real-world studies reporting on the effectiveness of neoadjuvant checkpoint inhibitors in early TNBC. Methods: Between November 2019 and December 2021, 63 early TNBC patients treated with anti-PD-1 antibodies (pembrolizumab or camrelizumab) or anti-PD-L1 antibody (atezolizumab) in combination with chemotherapy at seven institutions were included. PCR1 defined as ypT0/Tis and ypN0 was the primary endpoint. Secondary endpoints included pCR2 defined as ypT0/Tis, overall response rate (ORR), disease-free survival (DFS), drug-related adverse events (AEs) and biomarkers. Results: Among the patients in the current study, 34.9% of patients were able to achieve pCR1, and 47.6% of patients had achieved pCR2. The ORR was 82.5%. 33 patients with non-pCR2 tumors were found to have a median DFS of 20.7 months (95% CI 16.3 months-not reached). The DFS of patients with pCR2 and non-pCR2 after neoadjuvant therapy was significantly different (HR = 0.28, 95% CI 0.10–0.79; P = 0.038). The most common AEs were nausea (63.4%), fatigue (42.7%), leucopenia (30.0%) and elevated transaminase (11.7%). Conclusion: It is possible to achieve a meaningful pCR rate and DFS by combining neoadjuvant checkpoint blockade with chemotherapy in patients with high-risk TNBC. Compared to clinical trials, however, there was a slightly lower pCR rate in this multicentered real-world study. [ABSTRACT FROM AUTHOR]

As the pseudo-binary alloys between GeTe and Sb2Te3, GeSbTe-based compounds are promising thermoelectric materials. Although Ge2Sb2Te5 and GeSb2Te4 have widely been studied, the thermoelectric properties of GeSb4Te7 have not been well understood yet. In this work, we design a series of GeSb4-xBixTe7 solid solutions and systematically study the variation in the crystal structure, electrical, and thermal transport properties. Alloying Bi effectively reduces the carrier concentration and, thus, enhances the Seebeck coefficient. Meanwhile, the thermal conductivity is greatly reduced via large mass fluctuations. A maximum zT of 0.69 at 550 K and an average zT value of 0.52 between 300 and 700 K have been achieved for GeSb1.5Bi2.5Te7. These findings will promote the understanding and development of GeSbTe-based thermoelectric materials. [ABSTRACT FROM AUTHOR]

High-throughput sequencing, culture-dependent workflows, and microbiome transfer experiments reveal whether potassium phosphite (KP), an environmentally acceptable agricultural chemical, could specifically enrich the antagonistic bacterial community that inhibited the growth of the pathogen Ralstonia solanacearum. The application of KP enriched the potential antagonistic bacteria Paenibacillus and Streptomyces in soil, but depleted most dominant genera belonging to gram negative bacteria, such as Pseudomonas, Massilia, and Flavobacterium on day 7. Moreover, the KP-modulated soil microbiome suppressed R. solanacearum growth in soil. The predicted functions related to the synthesis of antagonistic substances, such as streptomycin, and the predicted functions related to tellurite resistance and nickel transport system were significantly enriched, but the synthesis of lipopolysaccharide (distinct component lipopolysaccharide in gram negative bacteria) were significantly depleted in the KP-treated soils. In addition, the copy numbers of specific sequences for Streptomyces coelicoflavus and Paenibacillus favisporus were significantly increased in the soil amended with KP, inhibited the growth of R. solanacearum, and had a higher tolerance of KP than R. solanacearum. Our study linked the application of fertilizers to the enrichment of antagonistic bacteria, which could support future work that aims to precisely regulate the soil microbiome to protect the host from infection by soil-borne pathogens. [ABSTRACT FROM AUTHOR]

Short carbon fiber-reinforced p-type skutterudite CeFe 4 Sb 12 composites were fabricated by a melting-annealing process combined with spark plasma sintering, the effect of carbon fibers on the thermoelectric and mechanical properties were investigated, and the relationship between the microstructure and the mechanical properties of the composites were elucidated. The results indicate that the carbon fibers were well distributed throughout the matrix and were in intimate contact with the CeFe 4 Sb 12 grains without interlayers. Both the flexural strength and the fracture toughness of CeFe 4 Sb 12 were enhanced with the addition of the carbon fibers. Considering the tradeoff between the thermoelectric and mechanical properties, the optimal carbon fiber content was found to be 1 vol.%. The flexural strength of the composite containing 1 vol.% fiber was improved by 53%, whereas the fracture toughness and ZT value remained nearly unchanged. [ABSTRACT FROM AUTHOR]

Metabolic adaptation is an emerging hallmark of cancer, as it provides tumor cells sufficient energy and metabolic intermediates. Although tumor cells are believed to highly rely on Warburg effect to satisfy their energy demand, more studies have pointed out that various types of tumor cells are highly dependent on oxidative phosphorylation to drive the tumorigenesis. Peroxisome proliferator-activated receptor-c coactivator 1α (PGC1α), the crucial member of PGC1 family, is aberrantly expressed in several cancer types, implicating its role in tumor proliferation, migration, invasion, metastasis, and chemoresistance. Numerous studies have reported that PGC1α participates in the regulation of tumor development by altering the transcriptional programs as well as the metabolic phenotypes. Thus, PGC1α-targeted therapy is therapeutically exploitable to target the metabolic vulnerabilities in tumor cells. This review mainly focuses on the current underlying mechanisms for its roles in regulating metabolic adaptation of tumor cells and its upstream regulators; how PGC1α participates in the regulation of the tumor proliferation, migration, invasion, metastasis, therapy resistance; and the feasibility of PGC1α-targeted therapy for cancer treatment. [ABSTRACT FROM AUTHOR]

The development of a rapid-forming in-situ sprayable hydrogel with the functions of tumor treatment and wound healing is essential for eliminating residual tumor tissue and promoting wound healing caused by surgical resection. On account of its semiconductor properties, β-FeSi 2 (FS) was widely explored as a thermoelectric material. In this work, FS was first applied as a bioactive material for the application of tissue engineering. Excitedly, we found that FS could be used as a novel antitumor agent. It exhibited excellent photothermal performance, and the released Fe ions could generate •OH under the acidic conditions and excessive H 2 O 2 in the tumor microenvironment. Moreover, the sprayable β-FeSi 2 -incorporated sodium alginate (FS/SA) hydrogel was prepared as an instant gelation after spraying in situ , contributing to timely tumor-induced skin wound healing and efficiently suppressing tumors through photothermal and chemodynamic therapy (PTT and CDT). Furthermore, the released bioactive Fe and Si ions could promote the migration and differentiation of endothelial cells and the pro-angiogenesis of skin wounds. Accordingly, such sprayable hydrogel played an effective role in emergency wound treatment with the advantage of convenience and portability. Overall, with incorporation of FS into the sprayable FS/SA hydrogel, the composite hydrogel possessed dual functions of tumor therapy and skin wound healing. [ABSTRACT FROM AUTHOR]

Coupling of a phase transition to electron and phonon transports provides extra degree of freedom to improve the thermoelectric performance, while the pertinent experimental and theoretical studies are still rare. Particularly, the impaction of chemical compositions and phase transition characters on the abnormal thermoelectric properties across phase transitions are largely unclear. Herein, by varying the Cu content x from 1.75 to 2.10, we systemically investigate the crystal structural evolution, phase transition features, and especially the thermoelectric properties during the phase transition for Cu x Se. It is found that the addition of over-stoichiometry Cu in Cu x Se could alter the phase transition characters and suppress the formation of Cu vacancies. The critical scatterings of phonons and electrons during phase transitions strongly enhance the Seebeck coefficient and diminish the thermal conductivity, leading to an ultrahigh dimensionless thermoelectric figure of merit of ∼1.38 at 397 K in Cu2.10Se. With the decreasing Cu content, the critical electron and phonon scattering behaviors are mitigated, and the corresponding thermoelectric performances are reduced. This work offers inspirations for understanding and tuning the thermoelectric transport properties during phase transitions. [ABSTRACT FROM AUTHOR]

Recently, a deformable and ductile inorganic semiconductor Ag2S has attracted intense attention due to its potential application in self-powered wearable and hetero-shaped electronics. However, the thermoelectric figure of merit (zT) of Ag2S is greatly limited by its extremely low carrier concentration. In this study, via doping I into Ag2S-based materials, we tune the carrier concentration into the optimal range as well as suppressing the lattice thermal conductivity. A maximum zT value of 0.26 is achieved for Ag2S0.7Se0.295I0.005 at 300 K, about three times higher than the matrix compound. More importantly, doping I has little effect on the ductility and deformability of Ag2S-based materials. Our study shows that I-doped Ag2S-based materials are good candidates for developing flexible thermoelectric technologies. [ABSTRACT FROM AUTHOR]

Keywords: defect engineering; flexible electronics; plastic inorganic semiconductors; thermoelectrics EN defect engineering flexible electronics plastic inorganic semiconductors thermoelectrics 1 1 1 06/21/21 20210617 NES 210617 In article number 2100883, Pengfei Qiu, Tian-Ran Wei, Xun Shi, and co-workers develop the first p-type plastic inorganic thermoelectric material. Thermoelectrics: p-Type Plastic Inorganic Thermoelectric Materials (Adv. Defect engineering, flexible electronics, plastic inorganic semiconductors, thermoelectrics. [Extracted from the article]

An tetraphenylethylene-based MOF (HNU-49) has been synthesized, which exhibits interesting piezofluorochromic behavior. Additionally, rhodamine B (RhB) can be successful encapsulated in HNU-49, to emit the characteristic dual-emission of RhB and the framework. The combination of host–guest interaction and piezofluorochromism can precisely modulate the luminescence to achieve near white-light. [ABSTRACT FROM AUTHOR]

Thermoelectric materials (TMs) can uniquely convert waste heat into electricity, which provides a potential solution for the global energy crisis that is increasingly severe. Bulk Cu 2 Se, with ionic conductivity of Cu ions, exhibits a significant enhancement of its thermoelectric figure of merit zT by a factor of ~3 near its structural transition around 400 K. Here, we show a systematic study of the electronic structure of Cu 2 Se and its temperature evolution using high-resolution angle-resolved photoemission spectroscopy. Upon heating across the structural transition, the electronic states near the corner of the Brillouin zone gradually disappear, while the bands near the centre of Brillouin zone shift abruptly towards high binding energies and develop an energy gap. Interestingly, the observed band reconstruction well reproduces the temperature evolution of the Seebeck coefficient of Cu 2 Se, providing an electronic origin for the drastic enhancement of the thermoelectric performance near 400 K. The current results not only bridge among structural phase transition, electronic structures and thermoelectric properties in a condensed matter system, but also provide valuable insights into the search and design of new generation of thermoelectric materials. [ABSTRACT FROM AUTHOR]

Achieving large Fermi energy splitting under illumination is critical for improving the performance of the photovoltaic devices. We conducted the energy band structure modulation of MoS 2 thin films to realize its photovoltaic operation on n-type c-Si and improve the photovoltaic performance of the formed MoS 2 /n-Si heterojunction solar cells. By capping with a MoO x overlayer, there is electrons orientation flowing from the valence band of MoS 2 into the O-deficiency states of MoO x due to their energy level overlap, which leads to the Fermi level downshift of the MoS 2 films and consequently its conductive type conversion. After the MoS 2 layer doped, we found that the built-in electric field of the fabricated MoS 2 /n-Si heterojunction devices greatly improved owing to the larger hetero-interface Fermi level differences. And, the defects recombination losses at the hetero-interface also reduced because of the holes selectively extracting effect of the O-vacencies in MoO x. As a result, the photo-generated carriers separation and extraction are both enhanced at the hetero-interface, so that the MoS 2 /n-Si devices exhibited excellent photovoltaic performance under the modulation doping effect. The conclusive power conversion efficiency of the doped MoS 2 /n-Si solar cells is of 5.47% with respectively optimized electrical parameters (V oc of 289 mV, FF of 60.72 and J sc of 31.25 mA/cm2). This observation of MoO x modulation doping effect on large-area sputtering MoS 2 could help in building a more appropriate interface carrier transport mechanism in photovoltaic and optoelectronic device applications of 2D materials. • The PV application of semiconducting MoS 2 on n-type c-Si is realized. • The energy band structure of MoS 2 is modulated by MoO x doping scheme. • Doping mechanism lies on carriers contact transfer due to energy band overlap. • Interface carriers transport efficiently enhanced by larger Fermi level splitting. • The PV performance of MoS 2 /n-Si devices improved significantly with MoO x doping. Achieving large Fermi energy splitting under illumination is critical for improving the performance of photovoltaic devices. In this work, we conducted the energy band structure modulation of MoS 2 thin films via MoO x doping scheme to realize its photovoltaic operation on n-type c-Si by magnetron sputtering. It is found that, by capping a MoO x overlayer, the MoS 2 electrons density decreased and the Fermi level shifted ~0.4 eV towards valence band, consequently the MoS 2 conductive type changing. With this doped MoS 2 layer, the built-in electric field of fabricated MoS 2 /n-Si heterojunction devices greatly improved and exceeded 400 mV owing to the larger interface energy-level differences. Meanwhile, the defects recombination losses reduced benefiting from the holes-selective behavior of O-deficiencies in MoO x , so that the photo-generated carriers extraction process were promoted. As a result, the doped MoS 2 /n-Si devices showed excellent rectification behavior with rectifying ratio to 105 and ideality of 1.12. The TRPL spectrums corroborated the enhanced carrier transport mechanism at MoS 2 /n-Si interface by MoO x modulation doping effect. Correspondingly, the significant improvement of doped MoS 2 /n-Si solar cells performance (V oc of 289 mV, FF of 60.72% and J sc of 31.25 mA/cm2) was achieved, exhibiting an optimized conversion efficiency of 5.47%. The UPS analysis revealed that the doping mechanism of MoO x /MoS 2 stacks lies in energy band overlap and electrons contact transfer between these two materials. This observation of MoO x modulation doping effect on large-area sputtering MoS 2 could help in building a better interface carrier transport in photovoltaic and optoelectronic applications of 2D materials. [ABSTRACT FROM AUTHOR]

In order to prevent the accidents in underground coal mines, an index system for safety supervision ability evaluation is established in the present paper. The index system is composed of goal layer, criteria layer (includes five indexes) and sub-criteria layer (includes 19 indexes). Based on the Analytical Hierarchy Process (AHP) method, the weight of each index within the system is determined. The analysis results indicate that the excess production is one of main indexes influencing the safety supervision ability. Subsequently, the causes underlying the excess production in underground coal mines are analyzed based on the 24Model. Moreover, the management measures are put forward. Thereafter, the safety supervision model for coal mine is proposed to prevent excess production. The functions of the proposed model are introduced in detail. Finally, Shanxi province is taken as a practical example to verify the capability of the established model. The application results show that the safety supervision model can realize the accurate monitoring of coal mine production, as well as improve the efficiency of safety supervision. With the model, the safety supervision ability of the branch of coal mine safety administration is effectively enhanced. [ABSTRACT FROM AUTHOR]

Inorganic semiconductors are vital for a number of critical applications but are almost universally brittle. Here, we report the superplastic deformability of indium selenide (InSe). Bulk single-crystalline InSe can be compressed by orders of magnitude and morphed into a Möbius strip or a simple origami at room temperature. The exceptional plasticity of this two-dimensional van der Waals inorganic semiconductor is attributed to the interlayer gliding and cross-layer dislocation slip that are mediated by the long-range In-Se Coulomb interaction across the van der Waals gap and soft intralayer In-Se bonding. We propose a combinatory deformability indicator (X) to prescreen candidate bulk semiconductors for use in next-generation deformable or flexible electronics. [ABSTRACT FROM AUTHOR]

Pseudo-binary GeSbTe alloys, best known as phase-change materials, are quasi-two-dimensional semiconductors in their stable trigonal phases with high electrical conductivity and low thermal conductivity, but their thermoelectric properties have not been systematically investigated. Here, in this letter, we prepared polycrystalline Ge2Sb2Te5, GeSb2Te4, and GeSb4Te7 bulk materials and studied the thermoelectric transport properties. Large anisotropy in Seebeck coefficient as well as in electrical conductivity is observed, which is not commonly reported in polycrystalline thermoelectric materials. Combining experimental study and theoretical calculations, one can find that this phenomenon is attributed to the asymmetry of a material's band structure. Maximal zT values of 0.46–0.60 are achieved at 750 K, indicating that GeSbTe-based compounds are promising thermoelectric materials for mid-temperature applications. [ABSTRACT FROM AUTHOR]

Through assembly of two metal ions (Li + and Zn 2+ ) and a quadridentate carboxylate ligand H 4 L1 (5-(bis(4-carboxybenzyl)amino)isophthalic acid), a new metal-organic framework ( HNU-22 , HNU is the abbreviation of Hainan University) was successfully constructed with the formula of ZnLi 2 (L1)(DMF)(H 2 O) (DMF = N , N ′-dimethylformamide). It should be noted that Li + and Zn 2+ are both involved in coordination, four Li + and two Zn 2+ , are connected together through the O atoms of the carboxylate ligand, forming the heteronuclear Li 4 Zn 2 cluster, which has never been reported in the literature. It is a rod-shaped metal cluster, and the linkage mode is Li-Zn-Li 2 -Zn-Li. When the metal clusters and organic ligands are simplified, HNU-22 can be regarded as a 4,8-connected topology with the flu symbol. Furthermore, HNU-22 shows luminescence sensing property toward Fe 3+ . [ABSTRACT FROM AUTHOR]