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Bimode temperature‐pressure sensors hold significant promise in personal health monitoring, wearables and robotic signal detection. Traditional bimode sensors typically combine two independent sensors, leading to fabrication complexity. This study develops a bimode temperature‐pressure sensor by using a facile electrodeposition method to create sandwiched BiSbTe/Carbon Paper/BiSbTe thin films and stacking them to a vertical structure. It demonstrates high sensitivity for temperature sensing, capable of detecting temperature difference as low as 1 K, and a rapid response time of 0.92 s due to a vertical structure. Utilizing its thermoelectric mechanism, the sensor achieves self‐powered sensing for finger touch and respiration states. Furthermore, its island‐like contact surface ensures high sensitivity with an extremely fast response time of 0.17 s, by rapidly changing contact resistance under pressure, allowing it to detect various human behaviors, including body movements and micro‐expressions. Beyond its sensing capabilities, the film excels in flexibility, electromagnetic interference shielding, and stability, presenting significant potential for integration into self‐powered electronic skin systems for health monitoring, wearables, artificial intelligence, and other electronic skin applications. [ABSTRACT FROM AUTHOR]

Graphene analog MXenes are the best options for interface engineering traditional thermoelectric materials. For the first time, a composite‐engineered TEG device composed of heavily doped bismuth and antimony telluride with incorporated Ti3C2Tx (MXene) nanoflakes is developed. Incorporated MXenes improved the electrical conductivity by carrier injection and reduces thermal conductivity by interfacial phonon scattering in both composites. The fabricated composite TEG device resulted in a maximum power of 1.14 mW and a power density of 6.1 mWcm−2. The fabricated composite TEG also demonstrates strong power generation stability and durability. Added MXenes improve the mechanical stability by employing a dispersion‐strengthening mechanism. Conclusively, the developed composite‐engineered TEG device is a facile and efficiency‐improving option for next‐generation bismuth telluride‐based commercial TEG devices. [ABSTRACT FROM AUTHOR]

This study introduces the synthesis of a hybrid thermoelectric material with enhanced conductivity and a high Seebeck coefficient, leveraging the properties of Te nanowires (NWs) and the conductive polymer PEDOT:PSS. Te NWs were synthesized using the galvanic displacement reaction. To further enhance conductivity, Ag-Te NWs were synthesized under optimized conditions via the Ag topotactic reaction, achieving desired results within 7 min using ethylene glycol and AgNO3. This hybrid material exhibited an electrical conductivity of 463 S/cm, a Seebeck coefficient of 69.5 μV/K at 300 K, and a power factor of 260 μW/mK2. These metrics surpassed those of conventional Te/PEDOT:PSS hybrids by a factor of 3.6, highlighting the superior performance of our approach. This study represents a significant advancement in thermoelectric materials, improving both conductivity and efficiency. [ABSTRACT FROM AUTHOR]

This study introduces the synthesis of a hybrid thermoelectric material with enhanced conductivity and a high Seebeck coefficient, leveraging the properties of Te nanowires (NWs) and the conductive polymer PEDOT:PSS. Te NWs were synthesized using the galvanic displacement reaction. To further enhance conductivity, Ag-Te NWs were synthesized under optimized conditions via the Ag topotactic reaction, achieving desired results within 7 min using ethylene glycol and AgNO3. This hybrid material exhibited an electrical conductivity of 463 S/cm, a Seebeck coefficient of 69.5 µV/K at 300 K, and a power factor of 260 µW/Mk². These metrics surpassed those of conventional Te/PEDOT:PSS hybrids by a factor of 3.6, highlighting the superior performance of our approach. This study represents a significant advancement in thermoelectric materials, improving both conductivity and efficiency. [ABSTRACT FROM AUTHOR]

An interest in the study of the structural and optical properties of topological insulators, led to the selection of Bismuth telluride thin films. Among the topological insulators, Bismuth telluride is one of the promising materials that exhibit applications in the field of thermoelectric power generation. The films were prepared using the thermal evaporation method under vacuum conditions of 10−5 mbar on glass substrates maintained at a temperature of 120∘C. The thickness of the film samples ranges from 400 Å to 1400 Å. Pure phases of Bi2Te3 with a rhombohedral structure are confirmed using X-ray Diffraction. The crystallite size was calculated using Debye–Scherrer’s formula. Structural morphology and compositions are examined using SEM and EDAX. The UV–Vis study reflects the optical behavior of the thin film samples. The absorption spectra gives the direct and allowed transition band gap of the Bi2Te3 thin film samples for various thicknesses. The band gap decreases with the increase in the thickness of the Bi2Te3 thin films, suggesting that the material has significant absorption towards the visible spectrum. The Photoluminescence (PL) emissions for Bi2Te3 thin film samples of various thicknesses are examined and analysed. Raman study reveals the presence of two active modes. [ABSTRACT FROM AUTHOR]

Thermoelectric Peltier coolers (PCs) are being increasingly used as temperature stabilizers for optoelectronic devices. Increasing integration drives PC miniaturization, requiring thermoelectric materials with good strength. We demonstrate a simultaneous gain of thermoelectric and mechanical performance in (Bi, Sb)2Te3, and successfully fabricate micro PCs (2 × 2 mm2 cross-section) that show excellent maximum cooling temperature difference of 89.3 K with a hot-side temperature of 348 K. A multi-step process involving annealing, hot-forging and composition design, is developed to modify the atomic defects and nano- and microstructures. The peak ZT is improved to ∼1.50 at 348 K, and the flexural and compressive strengths are significantly enhanced to ∼140 MPa and ∼224 MPa, respectively. These achievements hold great potential for advancing solid-state refrigeration technology in small spaces. [ABSTRACT FROM AUTHOR]

Bismuth telluride (Bi 2 Te 3) is gaining increasing attention as a material that exhibits flexo-photovoltaic effect in the infrared region, in addition to conventional thermoelectric materials and topological insulators. However, the flexo-photovoltaic effect is observed only when strains are applied to the Bi 2 Te 3 thin films by bending the substrates. To enhance the versatility of the flexo-photovoltaic effect, in this study, Bi 2 Te 3 thin films were sputtered onto a flexible substrate under a pre-curved condition, and strains were induced when the films were flattened. The crystal orientation and strains in the Bi 2 Te 3 thin films were affected by the pre-curved conditions. The Bi 2 Te 3 thin film deposited using a concave pre-curved condition exhibited an output voltage increase of approximately 15 % compared with the film deposited under a flat condition. This discovery suggests that strained Bi 2 Te 3 thin films can efficiently produce an output voltage under light irradiation without requiring a p–n junction, making them suitable for various photodetector applications. [ABSTRACT FROM AUTHOR]

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A memristor is a two-terminal electrical component with the scope of future computing applications and analog electronics. In this report, bismuth sulfide decorated one-dimensional carbon nitride nanotube was synthesized and characterized with various analytical techniques. The electrical property of the synthesized material was measured using a two-terminal metal–insulator–metal type of device that exhibited the resistive switching characteristics with the ON to OFF ratio of 2 × 103. The electron transport mechanism of the device was followed by Schottky emission and Poole–Frenkel emission for a low conductance state and Ohmic conduction behavior at the high conductance state. A decrease in the trap depth was identified in the simulation study with increasing applied potential and that supported the proposed mechanism. Read endurance and retention behavior of the device are stable in nature, supported by the statistical analysis. Furthermore, a hybrid logic gate was designed using two identical memristors, one CMOS inverter, one resistor, one voltage divider, and a buffer gate. The designed logic gate exhibited stable nand and nor gate operation based on the control signal. [ABSTRACT FROM AUTHOR]

[Display omitted] Organic thermoelectrics (TEs) based on carbon nanotubes (CNTs) have attracted much attention with their inherent advantages, such as, earth-abundant elements, broad electronic tunability, and excellent mechanical compliance. However, the inferior TE performance and doping stability of n-type CNTs to those of p-type CNTs have been bottlenecks to establish CNT-based next-generation TEs. Herein, we report a hybrid n-doping method that improves the n-type TE performance and long-term air-stability of water-processable single-walled CNT (SWCNT) and carboxymethyl cellulose (CMC) composite. The hybrid n-doping process with polyethyleneimine (PEI) n-dopant contains primary addition and secondary immersion doping, which causes a simultaneous increase in electrical conductivity and Seebeck coefficient through efficient n-doping and surface energy filtering effect, respectively. Furthermore, the hybrid-doped films exhibit superior long-term stability by inhibiting the oxidation of SWCNT/CMC at nanoscale, which allows to ensure the initial power factor even after storing in ambient for a month. Finally, we successfully demonstrated hybrid-doped SWCNT/CMC-based TEGs with long-term stable output characteristics. This work can offer insights to develop efficient and air-stable n-type organic TE materials and devices. [ABSTRACT FROM AUTHOR]

The thermoelectric (TE) properties of Nb-doped (CuI)0.003Bi2− x Nb x Te2.7Se0.3 compounds (x = 0, 0.005, 0.01 and 0.03), were investigated at temperatures ranging from 300 to 600 K. Among the compounds studied, the lightly substituted (CuI)0.003Bi1.995Nb0.005Te2.7Se0.3 compound exhibited the best TE performance due to the improvement in its electrical conductivity and its relatively unchanged Seebeck coefficient due to Nb doping. Its figure of merit, ZT, was greater than the undoped (CuI)0.003Bi2Te2.7Se0.3 compound for the temperature range investigated. In particular, the ZT of (CuI)0.003Bi1.995Nb0.005Te2.7Se0.3 reached a value of 0.65 at 448 K in this study. [ABSTRACT FROM AUTHOR]

The thermoelectric (TE) properties of Nb-doped (CuI)0.003Bi2− x Nb x Te2.7Se0.3 compounds (x = 0, 0.005, 0.01 and 0.03), were investigated at temperatures ranging from 300 to 600 K. Among the compounds studied, the lightly substituted (CuI)0.003Bi1.995Nb0.005Te2.7Se0.3 compound exhibited the best TE performance due to the improvement in its electrical conductivity and its relatively unchanged Seebeck coefficient due to Nb doping. Its figure of merit, ZT, was greater than the undoped (CuI)0.003Bi2Te2.7Se0.3 compound for the temperature range investigated. In particular, the ZT of (CuI)0.003Bi1.995Nb0.005Te2.7Se0.3 reached a value of 0.65 at 448 K in this study. [ABSTRACT FROM AUTHOR]

Relativistic ratcheting of Dirac fermions on the surface of topological insulator Bi 2 Se 3 attached to a spiral multiferroic oxide is investigated. We find that the Dirac fermions on the surface of topological insulator Bi 2 Se 3 exhibit pronounced Brownian motion, tuned by the strength of exchange field established by the interaction of spin degrees of Dirac fermions and multiferroic oxide. The surface Dirac fermions show ratchet effect as a net current under the influence of orthogonal, commensurate ac drives in the presence of a symmetric periodic potential set by the exchange field. [ABSTRACT FROM AUTHOR]

Organic–inorganic hybrid thermoelectric (TE) materials have attracted tremendous interest for harvesting waste heat energy. Due to their mechanical flexibility, inorganic‐organic hybrid TE materials are considered to be promising candidates for flexible energy harvesting devices. In this work, enhanced TE properties of Tellurium (Te) nanowires (NWs)‐ poly (3‐hexylthiophene‐2, 5‐diyl) (P3HT) hybrid materials are reported by improving the charge transport at interfacial layer mediated via controlled oxidation. A power factor of ≈9.8 µW (mK2)−1 is obtained at room temperature for oxidized P3HT‐TeNWs hybrid materials, which increases to ≈64.8 µW (mK2)−1 upon control of TeNWs oxidation. This value is sevenfold higher compared to P3HT‐TeNWs‐based hybrid materials reported in the literature. MD simulation reveals that oxidation‐free TeNWs demonstrate better templating for P3HT polymer compared to oxidized TeNWs. The Kang–Snyder model is used to study the charge transport in these hybrid materials. A large σE0 value is obtained which is related to better templating of P3HT on oxygen‐free TeNWs. This work provides evidence that oxidation control of TeNWs is critical for better interface‐driven charge transport, which enhances the thermoelectric properties of TeNWs‐P3HT hybrid materials. This work provides a new avenue to improve the thermoelectric properties of a new class of hybrid thermoelectric materials. [ABSTRACT FROM AUTHOR]

The multi‐beam discharge plasma sintering (MB‐SPS) method is successfully applied to the preparation of Bi2Te3‐based thermoelectric (TE) films with insulating substrates. Herein, the impact of uniaxial stress on the microstructure evolution and TE performance are explored systematically. The results indicate that the increase of uniaxial stress promotes the preferential growth of Bi0.5Sb1.5Te3 (BST) grains along the (000l) crystal plane, leading to the remarkable increase in carrier mobility. The maximum (000l) preferential orientation factor reaches 80% for the BST/epoxy (EP) film sintered under 25 MPa, which is 3.08 times higher than that of BST/EP film sintered at 10 MPa. While the highest power factor reaches 2.36 mW m−1 K−2 at 300 K for the BST/EP film sintered under 20 MPa, increased by 97% as compared with that of the film sintered under 10 MPa. This work once again confirms that the MB‐SPS technology is an effective approach to prepare high‐performance Bi2Te3‐based films with insulating substrates and demonstrates that the (000l) preferential orientation and TE performance of the films can be further enhanced by an appropriate uniaxial stress. [ABSTRACT FROM AUTHOR]

As the global demand for tellurium (Te) increases, it is crucial to develop efficient recovery methods that consider existing supply streams. This research combines gravity separation and froth flotation processes to enhance the recovery of Te minerals from tailings produced during the beneficiation of copper porphyry ores. Prior to processing, a systematic and comprehensive characterization study of copper tailing (CT) samples was conducted to examine the deportment of Te minerals in different mineral phases and to understand their locking and liberation behavior. Characterization techniques included inductively coupled plasma mass spectrometry (ICP-MS) and TESCAN's integrated mineral analysis (TIMA). Copper tailing characterization showed that minerals with gold (Au), silver (Ag), bismuth (Bi), and Te were present in various forms, including native Au, electrum, tellurides, and sulfosalts. TIMA revealed that >90% of these minerals were primarily hosted in pyrite as less than 10 µm inclusions in the CT. TIMA also revealed that Te minerals exhibited fine-grained liberation of less than 20 μm. Moreover, TIMA results showed that >80% of mica and other silicate minerals were concentrated in size fractions < 38 μm, suggesting that desliming processes would positively impact Te enrichment. The results from the processing tests showed a Te recovery rate of ~77% and a Te enrichment ratio of 13 when using the combination of gravity separation and froth flotation at 90 g/t xanthate collector and 50 g/t glycol frother. The findings from this study show a significant potential for Te recovery from unconventional sources if appropriate physical beneficiation approaches are adopted. [ABSTRACT FROM AUTHOR]

Solar photovoltaic (PV) systems, coupled with thermo-electric cooling, have gained significant attention as an eco-friendly solution. To enhance energy efficiency and reduce the overall environmental impact of energy generation and consumption, it is a viable option. This study investigates the impact of critical parameters, namely inclination angle of solar panels, the type of material used in thermo-electric cooling modules, on the performance of a solar PV-thermo electric cooling system. In this research, the impact of inclination angles (15°, 20°, 25°) and two materials (Bismuth telluride and Peltium telluride) of thermoelectric were considered for this study. A comprehensive series of experiments were conducted to analyze the impact of varying inclination angles of the solar panels and material of thermoelectric cooler. The average incident irradiation, panel temperature and outpower of solar panel variation with time are presented. The optimum tilt angle of the solar panel is observed as 20° and material for thermoelectric cooler is Bismuth telluride. When using Bismuth telluride as a thermoelectric material with 20° tilt angle, the solar panel's temperature decreases by 14% and its outpower is augments by a maximum of 14.5%. The results presented here offer practical guidance for system design and operation, ultimately promoting the widespread adoption of this technology in a more environmentally conscious manner. [ABSTRACT FROM AUTHOR]

The thermal transport and thermoelectric properties of CsCdX3 (X = Cl, Br) were investigated using first-principles calculations and machine learning interatomic potentials. The lattice thermal conductivity was obtained including the effect of temperature on the phonon dispersion spectrum and the contribution of the diffuson-like phonons, based on the self-consistent phonon (SCP) and two-channel phonon transport theories. We found that diffuson-like phonons contribute significantly to the lattice thermal transport. The ultralow lattice thermal conductivities of CsCdCl3 and CsCdBr3 at 300 K are 0.95 W/mK and 0.57 W/mK, respectively. The large Seebeck coefficient of CsCdCl3 and CsCdBr3 is about 800 μV/K and 700 μV/K at 900 K, due to the multi-valley energy band structure. The calculated maximum ZT of p-type CsCdBr3 is 1.16 at 900 K, larger than most of the reported halide perovskite materials. We suggest that CsCdBr3 is a promising candidate for thermoelectric halide perovskite materials. [ABSTRACT FROM AUTHOR]

In this work, we examine the formation of iron-based magnetic domains on two-dimensional (2D) single-crystal bismuth telluride plates. Using solvothermal chemical methods, 2D bismuth telluride (Bi2Te3) single crystalline nanoplates were reacted with iron salts (FeCl2) to achieve electrical doping. The use of a reducing agent [L(+)-ascorbic acid] along with FeCl2 resulted in homogeneous dispersion of iron across the crystal, whereas non-reduced iron doping achieved edge growth of iron/iron oxide nanoparticles. High-resolution analytical electron microscopy was used to examine the iron nanoparticle accumulation and morphology at nanoplate edges for non-reduced materials and iron dispersions within the crystals in the case of reduction. Our analysis revealed little variation in the atomic uptake of iron in any form over a range of solution-dopant concentrations. However, structural analysis and transport measurements clearly indicate the tendency of the dopant nanoparticles to oxidize quickly. The Seebeck coefficient and power factor also express modifications with exposure to oxidation, providing an indirect probe of the dopant modification to the host Bi2Te3's electronic properties. Importantly, however, magnetic force microscopy images show a distinct difference in the formation of magnetic phases with and without the use of reducing agents during iron doping. This suggests that oxidation post-doping does not form magnetic phases, whereas oxidation during the doping process is suitable for obtaining magnetically doped Bi2Te3 nanocrystals. [ABSTRACT FROM AUTHOR]

Exploring thermoelectric materials with high performance and low cost is of great importance in mitigating environmental and energy challenges. Here, we provide an atomistic insight into strain-induced enhancement of thermoelectric performance in potassium-based halide double perovskite K2SnX6 (X = I, Br, Cl) using first-principles calculations. To get reliable predictions for transport properties, we adopt advanced methods such as self-energy relaxation time approximation for electron transport and unified theory for lattice transport in combination with self-consistent phonon approach. Our calculations highlight a promising thermoelectric figure of merit ZT over 1.01 in K2SnI6 when applying a compressive strain of −6%, being tenfold larger than those in the uncompressed compounds, suggesting that compressing is an effective way to enhance the thermoelectric performance of halide double perovskites. [ABSTRACT FROM AUTHOR]

Here, we demonstrate a strategy for the quantification of electron–phonon interaction (EPI) of bismuth telluride (Bi2Te3) under hydrostatic pressure through systematic femtosecond pump-probe spectroscopy. Two optical phonon modes, namely A 1 g and Eg with frequencies of 1.87 and 3.71 THz at ambient pressure, are detected using time-resolved transient reflection (TR) measurement. Frequencies of both coherent phonon oscillations increase monotonically by around 33% and 17%, respectively, with the rising pressure up to 5.67 GPa, indicating pressure-induced phonon-hardening effect. The mode-specific electron–phonon coupling constant λ of Bi2Te3 under different pressures are calculated with the frequency of the A 1 g mode. It turns out that the variation of phonon lifetime and the corresponding phonon dephasing rate of the A 1 g mode may result from the pressure modification of λ. Our findings reveal the significant role of EPI in phonon transport and shed light on further manipulation on thermoelectric efficiency of Bi2Te3 with external strain. [ABSTRACT FROM AUTHOR]

Conventional production of adiponitrile (ADN), an important chemical in energy storage devices and the nylon industry, is mainly by hydrocyanation of butadiene, which requires multiple reaction steps, energy-intensive conditions, and the use of toxic hydrogen cyanide. Electrosynthesis of ADN via the electrohydrodimerization of acrylonitrile (EHD-AN) with water as the proton source serves as a less energy-intensive and green synthetic alternative to hydrocyanation of butadiene, but the cathode materials used in the EHD-AN process are limited to highly toxic heavy metals (e.g., Cd, Pb). To mitigate the environmental impact of heavy metal pollution, the exploration of high-performance cathode materials with low toxicity is, therefore, of great importance. Herein, we report on a bismuth-modified electrode, prepared by facile electrochemical deposition, as an efficient and robust electrocatalyst towards the electrosynthesis of ADN. The effects of electrode preparation conditions (e.g., charge passage, use of a nanostructured template) and the electrosynthetic conditions (e.g., concentration of quaternary alkyl ammonium salt, AN concentration, electrolyte pH, applied potential) on the electrocatalytic performance of the bismuth-modified electrodes were thoroughly studied through a series of controlled-potential electrolysis (CPEs). Under optimal conditions, the bismuth nanosheet modified electrode (nanoBi) was demonstrated, for the first time, to exhibit a remarkably high selectivity (81.21 ± 1.96%), ADN generation rate (1.28 ± 0.20 mmol cm−2 h−1), and activity, in terms of turnover frequency based on the electrochemically accessible amount of metal species (1.65 ± 0.01 s−1) at a moderate potential of −1.03 V vs. RHE, which makes bismuth a promising alternative to the toxic electrode materials currently used in industrial ADN production. Besides, the developed nanoBi electrode is immune to electricity fluctuation, which enables its integration with renewable and green electricity sources for the low-carbon footprint production of ADN. Finally, the scale-up electrosynthesis of ADN at an industrially relevant current density using a divided flow-type electrolyzer was also demonstrated. [ABSTRACT FROM AUTHOR]

Reticular chemistry has been a cornerstone in the design of novel 2D materials. Despite numerous possibilities for topological arrangements, only a few with high symmetry can form stable networks. Here, starting from 2D carbons, four types of highly stable tessellations are discovered, which consist of chains of non‐hexagonal rings separated by hexagonal ribbons. A modified Read–Shockley model is established to perfectly describe the stability of these highly stable frameworks, which is based on the interaction between non‐hexagonal rings. Moreover, these four types of tessellations and the modified Read–Shockley model are found to be of general validity in designing highly stable 2D materials, which is verified by the calculations on polymorphs of boron nitride and molybdenum disulfide. Besides, among the studied 2D carbon allotropes, two semi‐metallic structures with highly anisotropic Dirac cones and one semimetal with a Dirac nodal line at the Fermi level are discovered, as protected by their D2h symmetry. Spin‐orbital coupling is further found to open small bandgaps for these three Dirac structures, making them nontrivial topological insulators. The in‐depth understanding of the stability of 2D crystals in this study provides a new way for rational design of 2D crystals that may show peculiar electronic structures. [ABSTRACT FROM AUTHOR]

The contact resistivity originating from the metal–semiconductor interface is a crucial factor for conversion efficiency of thermoelectric films devices. Due to anisotropic nature of state‐of‐art Bi2Te3 films, the contact resistivity also needs to match with the different orientations in/out‐plane film configurations. Here, a series of bismuth telluride (Bi2Te3) films with different orientations are deposited, and the contact resistivity between Ti/Cr/Cu and Bi2Te3‐based films is studied in detail. The increased (00l) orientation can effectively reduce the contact resistivity mainly due to the enhanced Tunneling effect. Finally, a low contact resistivity of 0.84 µΩ cm2 is observed in highly (00l)‐orientated Bi2Te3 film in contact with Cr. This work provides an effective method to control contact resistivity by adjusting the orientation of film, and also provides guidance on how to further improve the performance of thin film‐TEDs with different configurations. [ABSTRACT FROM AUTHOR]

Oxides are of interest for thermoelectrics due to their high thermal stability, chemical inertness, low cost, and eco‐friendly constituting elements. Here, adopting a unique synthesis route via chemical co‐precipitation at strongly alkaline conditions, one of the highest thermoelectric performances for ZnO ceramics (PFmax=$PF_{\text{max}} =$ 21.5 µW cm−1 K−2 and zTmax=$zT_{\text{max}} =$ 0.5 at 1100 K in Zn0.96Al0.04O${\rm Zn}_{0.96} {\rm Al}_{0.04}{\rm O}$) is achieved. These results are linked to a distinct modification of the electronic structure: charge carriers become trapped at the edge of the conduction band due to Anderson localization, evidenced by an anomalously low carrier mobility, and characteristic temperature and doping dependencies of charge transport. The bi‐dimensional optimization of doping and carrier localization enable a simultaneous improvement of the Seebeck coefficient and electrical conductivity, opening a novel pathway to advance ZnO thermoelectrics. [ABSTRACT FROM AUTHOR]

The New Journal of Chemistry, published by The Royal Society of Chemistry and the Centre National de la Recherche Scientifique, contains a variety of articles on different topics in chemistry. The articles cover areas such as polydimethylsiloxane coatings, water oxidation, lithium-ion batteries, and photocatalytic reactions. The journal provides valuable insights for those interested in chemistry and covers a diverse range of research areas. The document is a list of research papers published in the journal Chemistry in 2024, including topics such as the electrocatalytic degradation of tetracycline, the construction of a supramolecular system for imaging nematic mesophase and nematode cells, insights into hydrogen bond strengths in microhydrated clusters, and the development of macrophage-red blood cell hybrid membranes for eliminating pathogens, endotoxins, and heavy metal ions from blood. [Extracted from the article]

Fiber‐based flexible thermoelectric (TE) generators are highly desirable due to their capability to convert thermal energy into electricity and their potential applications in wearable electronics. High‐performance poly(3,4‐ethylene dioxythiophene):poly(styrene sulfonate) (PEDOT:PSS)/Tellurium (Te) composite TE fibers have been successfully developed via a continuous wet‐spinning approach followed by sulphuric acid treatment. With a simple pre‐modification to Te nanowires, the inorganic Te fillers form uniform distribution in PEDOT:PSS. At the optimal condition, the composite fibers exhibit a power factor of 233.5 µW m−1 K−2 and mechanical strength of 205 MPa, which are among the highest values reported so far for the PEDOT:PSS‐based TE fibers. From the viewpoint of TE property enhancement mechanism, understanding the morphology and carrier transport behavior in the 1D organic/inorganic composite fibers remains still challenging. On basis of a series of PEDOT:PSS/Te composite fibers with varying Te fractions, orientations of both the inorganic and organic constituents are quantitatively evaluated. Their electrical conductivities and Seebeck coefficients are also analyzed with modified series‐parallel models and energy filtering theory. This work may not only provide a universal approach to produce high‐performance organic/inorganic composite TE fibers for various wearable applications, but also help to understand the morphology and charge transport between heterogeneous phases in a 1D composite. [ABSTRACT FROM AUTHOR]

TeO2-Bi2O3-B2O3-ZnO laser glasses doped with Er3+ were synthesized through an optimized melt-quenching method. The absorption spectra at 808 nm LD pumping were studied. Various spectral tests and data analyses indicate that the maximum fluorescence emission intensity can be obtained when the Er3+ doping concentration reaches 2%. In this case, the emission cross-section can reach up to 9.12 × 10−21 cm2 and the gain coefficient at 1.55 μm is 6.17 cm−1. Simultaneously, the sample has a lower phonon energy in the high-frequency band at 1077 cm−1, which reduces the probability of non-radiative relaxation. The calculated energy transfer coefficient CD-A is 13.8 × 10−40 cm6/s, reflecting the high cross-relaxation probability of Er3+ in the sample, which promotes the luminescence of 1.55 μm and favors the emission in the near-infrared region. The comprehensive results demonstrate that the prepared Er3+-doped bismuth telluride laser glass can be used as a promising and high-quality gain material for near-infrared lasers. [ABSTRACT FROM AUTHOR]

For thermoelectric applications at high temperatures, perovskite SrTiO3 is a promising contender as an n‐type oxide thermoelectric (TE) material. In this work, SrxLa0.1TiO3−δ/TiO2−y composite ceramics were successfully synthesized by solid state reaction, using a combination of A‐site cation vacancy and composite fabrication. Through X‐ray diffractometer and scanning electron microscopy analysis, a complex microstructure composed of two kinds of titanium oxides was formed after reductive sintering and annealing. In addition, controlling the content of Sr vacancies in the SrxLa0.1TiO3−δ matrix increased the thermoelectric power factor (PF) by optimizing the weighted mobility in the composite, resulting in the highest PF of 425.8 μW m−1 K−2 and the maximum ZT of 0.16 for the Sr0.875La0.1TiO3−δ/TiO2−y composite through the synergistic optimization of electrical and thermal transport properties. The strategy proposed in this study of design A‐site‐deficient composites with nano‐sized metal paved a new way to fabricate high performance oxide thermoelectric materials. [ABSTRACT FROM AUTHOR]

An efficiently aerobic dehydrazination of arylhydrazines promoted by potassium tert‐butoxide (tBuOK) is detailed in this study. This method smoothly produces aromatics analogues from arylhydrazines using catalytic amount of tBuOK under practical conditions, exhibiting excellent functional group tolerance and a broad substrate scope. The application potential of this approach is further demonstrated through the preparation of deuterated, iodinated and brominated aromatics. Moreover, it shows that this aerobic base‐mediated dehydrazination could be utilized to prepare unsymmetrical aryl sulfides, selenides and tellurides with high efficiency. [ABSTRACT FROM AUTHOR]

Polymer‐based chalcogenide composites are gaining attention for thermal energy storage thermoelectric (TE) applications due to their high Seebeck coefficient (S) and electrical conductivity (σ), compared to low thermal conductivity of polymers without electrical optimization. This combination can enhance power factor and ZT while suppressing drawbacks. The energy‐filtering effect of polymer/chalcogenide interfaces may also improve TE performance, further enhancing the potential for improved TE applications. In this work, Poly(3,4‐ethylenedioxythiophene) (PEDOT) was functionalized with selenium (Se), and its structural and thermoelectric (TE) properties were studied. The variations of σ and S, with higher percent of Se content, displays a simultaneous rise in both σ and S values, which is noteworthy. The probable reason behind this increment of both σ and S values is due to the improvement in charge transport in the composites due to a percolating network formed between the Se nanoparticles and PEDOT along with the carrier energy filtering interaction between PEDOT and Se. The highest room temperature ZT value obtained is 0.027 for 82 % of Se content in PEDOT, which is comparable with bulk nanostructured organic‐inorganic hybrid composite materials. This work presents an efficient technique for enhancing the TE properties of polymers through inorganic functionalization. [ABSTRACT FROM AUTHOR]

In this work, we present a solvothermal, in situ doping methodology for synthesizing crystalline doped 2D bismuth telluride (Bi2Te3) nanoplates. Isoelectronic antimony (Sb) substitution at the bismuth (Bi) site is chosen to minimize the lattice strain in the nanostructure. Using a combination of x-ray techniques and electron microscopy, we demonstrate that the rhombohedral crystal structure (space group R 3 ̄ m), characteristic of Bi2Te3 is preserved in few-quintuple-layer, hexagonal nanoplates. Our findings reveal a uniform dispersion of Sb within the nanoplates up to an atomic concentration of 1%. Beyond this threshold, a disordered SbTe alloy begins to form along the crystal edges in addition to Sb substitution at the Bi sites in the bulk, restricting further growth of the nanoplates. In addition, we examine the different stresses that develop within the nanoplates as lattice strain increases due to Sb substitution. This study provides fundamental insights into the dopant's effect on the self-assembled growth of electronically relevant 2D crystals. [ABSTRACT FROM AUTHOR]

This study aimed to enhance the thermoelectric properties of bismuth telluride by adding Bi4O4SeCl2 (BOSC). Commercial N-type bismuth telluride was mixed with BOSC powder in varying concentrations. As the BOSC content increased, the carrier concentration also rose due to chlorine atoms acting as donor impurities. Despite this increase, the power factor values of the samples with BOSC additives did not significantly differ from those of the bare bismuth telluride sample. However, the total thermal conductivity decreased significantly with the addition of BOSC, reaching a minimum value of 0.54 W·m–1·K–1 at 150 °C for the sample with 1 wt% BOSC. Notably, the ZT value for the sample with 1 wt% BOSC was about 0.86, which is four times higher than that of the bare bismuth telluride sample. Our findings demonstrate superior thermoelectric performance, indicating a more efficient modification of thermoelectric properties through the addition of BOSC to the bismuth telluride matrix.

The switching ratio of a thermal switch is a key design parameter, and electrically activated switches based on thermoelectric effects have been reported to produce large switching ratios over a wide range of temperatures. Previous switches based on the Seebeck effect have switching ratios that are limited by the thermoelectric figure-of-merit z T. Perhaps, more importantly, they are limited by their device construction of alternating p-type and n-type materials with soldered junctions. Alternatively, we show that semiconducting polymers with spatially graded doping can offer similar switching ratios due to a volumetric heat absorption effect. This occurs in heavily doped polymers, which exhibit a sharp decrease in the Seebeck coefficient as charge carriers become fully delocalized. Such heat absorption is analogous to the Thomson effect, where heat is locally absorbed due to temperature-dependent variation of the Seebeck coefficient. Here, a theoretical model is derived to solve the 1D heat equation with spatially graded doping, allowing for optimization of the doping profile for a given material system. Four different material systems are compared according to an analysis of reported measurements to determine the upper limit of the switching ratio. A hypothetical Thomson switch based on poly(3,4-ethylenedioxythiophene) doped with ferric tosylate can produce switching ratios up to 12 under a thermal bias of 10 K, a threefold increase compared to a Peltier switch of the same material. Like a Peltier switch, the switching ratio of a Thomson switch diverges under a small thermal bias. Under a large thermal bias, the switching ratio converges toward that of an equivalent Peltier switch. [ABSTRACT FROM AUTHOR]

Using first-principles density functional theory based approach, we investigate the tunability of the thermoelectric properties of perovskite MgSiO3. We find that the thermoelectric properties are strongly correlated with the electronic structure and can, therefore, be modulated with uni-axial tensile and compressive strains. Key thermoelectric parameters, such as the Seebeck coefficient (S), show non-monotonic behavior, displaying large shifts with the application of 1 % uni-axial tensile strain. The relevance of this small strain value also appears in structural distortion of the oxygen octahedra and band convergence in the electronic band structure. The band structure modifications also introduce a strong strain dependence of the relaxation time, as defined within the deformation potential approach. As a result, an improvement of up to 35 % is observed in zT with the application of 1 % tensile strain. Our results highlight a possible new route to improving thermoelectric performance in perovskite oxide thermoelectrics. [ABSTRACT FROM AUTHOR]

We use Peltier cooling to experimentally determine the thermoelectric figure-of-merit of a material, where the maximum temperature depression, ΔTmax, is simply related to Z of a thermocouple. However, for thermocouples comprising good thermoelectric materials with Z T ≥ 1 , ΔTmax can be large (≥100 K), making it difficult to assign the measurement to a particular temperature. This is less of a problem if the thermocouple consists of a semiconductor and a metal since ZT and ΔTmax are then much smaller. We developed a procedure for measuring the dimensionless figure-of-merit of a semiconductor using semiconductor-metal thermocouples in which the form factor (i.e., the ratio of areas to lengths of the two branches) is optimized. We also show valuable aspects in the ΔTmax measurement when the material dimensions are varied. Our experiments on couples consisting of a bismuth telluride alloy and constantan, and the corresponding theoretical analysis, show that the radiation losses are significant at ordinary temperatures. A good estimate of thermal conductivity and zT of the sample can be obtained when radiation losses are minimized. [ABSTRACT FROM AUTHOR]

Neuromorphic visual systems based on optogenetic techniques have colossal potential for in‐memory computing with prospects of developing artificial intelligence vision systems. However, conventional transistor architectures face formidable challenges in efficient signal processing owing to limitations in the intrinsic properties of active channel materials. In this work, a novel transition metal telluride‐sulfide hybrid heterojunction‐based optoelectronic synaptic phototransistor is proposed, in which UV–vis responsive zinc oxide encapsulated few‐layer tungsten disulfide channel is decorated with near‐infrared sensitive 0D cobalt ditelluride (CoTe2) nanocrystals (NCs), eliciting the ability to sense, store, and process optical signals across a broad range of the electromagnetic spectrum. This meticulously designed three‐layered heterostructure, based on their interfacial band alignments, enables high photoresponsivity up to ≈2.6 × 103 A W−1 at a back‐gate bias of 20 V, leading to the brain‐inspired synaptic applications with an average power consumption as low as 75 pJ for each training process. The device exhibits excitatory postsynaptic current, paired‐pulse facilitation with an index above 150%, as well as light‐modulated synaptic plasticity by mimicking biological synapses, which mainly originate from trapped holes in Co‐vacancy mediated surface defect states of CoTe2 NCs. Hence, this 2D material‐based hybrid phototransistor appears to be a promising candidate for energy‐efficient next‐generation brain‐inspired neuromorphic vision systems. [ABSTRACT FROM AUTHOR]

The development of new sulfide and selenide-based thermoelectric (TE) materials is critical for the mass production of TE devices due to the higher earth abundance of S/Se than Te. In this work, we have prepared single crystals of Ag-substituted BaCu2−xAgxSe2 (x = 0 – 0.8) by direct fusion of elements at high temperatures. As characterized by single crystal X-ray diffraction (SCXRD) studies, each of the structures (space group: Pnma) contains two transition metal sites (M1 and M2), and the Ag atoms are disordered with Cu atoms at both sites with a slight preference for the M2 site. Phase pure polycrystalline BaCu2−xAgxSe2 (x = 0 – 1.0) samples have also been synthesized, which are semiconductors as confirmed by optical absorption and resistivity studies. All these samples show positive values of the Seebeck coefficient, suggesting the p-type electrical conduction. Our thermal conductivity (ktot) studies demonstrate a remarkable drop in ktot values on increasing the Ag-substitution in the BaCu2−xAgxSe2 phases with the lowest ktot value of 0.33 W m−1 K−1 (673 K) for the x = 1.0 sample. Our studies show the potential of the BaCuAgSe2 for TE applications with higher zT values if the hole concentration of the phase can be fully optimized. [ABSTRACT FROM AUTHOR]

Thermoelectric materials convert heat into electricity, with a broad range of applications near room temperature (RT). However, the library of RT high‐performance materials is limited. Traditional high‐temperature synthetic methods constrain the range of materials achievable, hindering the ability to surpass crystal structure limitations and engineer defects. Here, a solution‐based synthetic approach is introduced, enabling RT synthesis of powders and exploration of densification at lower temperatures to influence the material's microstructure. The approach is exemplified by Ag2Se, an n‐type alternative to bismuth telluride. It is demonstrated that the concentration of Ag interstitials, grain boundaries, and dislocations are directly correlated to the sintering temperature, and achieve a figure of merit of 1.1 from RT to 100 °C after optimization. Moreover, insights into and resolve Ag2Se's challenges are provided, including stoichiometry issues leading to irreproducible performances. This work highlights the potential of RT solution synthesis in expanding the repertoire of high‐performance thermoelectric materials for practical applications. [ABSTRACT FROM AUTHOR]

In this paper, we report the synthesis and characterization of a new material, (HFlucytosine)2BiCl5. The structure studied by single crystal X-ray diffraction reveals one-dimensional (1D) il [BiCl5]n2− chains surrounded by protonated flucytosine antifungal drug (HFlucytosine)+. The structure is stabilized by hydrogen bonds and non-covalent interactions. These interactions were assessed using Hirshfeld surface analysis. The optical property of the compound was studied with a focus on the band gap. Theoretical calculations on the electronic structure, band gap, and frontier molecular orbitals were performed using density functional theory (DFT) and time-dependent DFT (TD-DFT) to support our experimental findings. Our results indicate that the energy gap (Eg) and the chemical reactivity descriptors are primarily linked to the ring of the organic cation and the inorganic anion. This highlights the importance of these two components in determining the activity and antioxidant capacity of the molecule. To ascertain the efficacy of these compounds in inhibiting the proliferation of detrimental bacteria, which are prevalent environmental contaminants in the Arab region, an agar disc diffusion assay was performed. [ABSTRACT FROM AUTHOR]

The five Starra iron oxide copper–gold (IOCG) deposits, which are located in the Cloncurry district of the Mount Isa Inlier, NW Queensland, are hosted in a N-trending zone of deformed iron-rich metasedimentary rocks that are underlain by two mineralogically distinct mafic–intermediate meta-igneous rocks. Copper–Au mineralisation is subdivided into two stages—an early main stage that transitioned from a magnetite-dominated Cu substage comprising chalcopyrite, pyrite, biotite and chlorite, to a hematite–muscovite-bearing Cu–Au substage with chalcopyrite, bornite and rare chalcocite, as well as Au–Ag-tellurides and native Au. This second stage was followed by a subordinate but nonetheless important carbonate–quartz–barite vein stage with minor but locally high-grade Cu–Au mineralisation characterised by abundant chalcocite and bornite, minor native bismuth and wittichenite (Cu3BiS3), together with minor Au–Ag telluride minerals. Bornite in these carbonate–quartz–barite veins contains considerable amounts of Au (>10 ppm), which appears to be deported either as lattice substitution in the bornite crystal structure or as homogeneously distributed Au0 nanoparticles. An earlier, coarse-grained mafic intrusion was affected by early Na–Ca alteration, whereas a second mafic intrusion lacks evidence of Na–Ca alteration but was exposed to K–Fe alteration and subsequent mineralisation at Starra 222. Mushketovite (magnetite after specular hematite) is only observed in ironstone lodes proximal to the mafic–intermediate rocks. The close spatial and mineralogical associations of the mafic–intermediate bodies and the ironstone lodes point to a stronger link between magmatic activity and IOCG mineralisation than has previously been recognised at Starra. Remobilisation of gold by late-stage hydrothermal fluids aided by the relatively low fluid temperatures during the main pulse of Cu–Au mineralisation refined gold grades at Starra, making it a relatively gold-rich IOCG deposit. We show that the Cu–Au deposits of the Starra trend feature mineralogical and geochemical elements common to both Cloncurry IOCG deposits (e.g. abundant magnetite) and IOCG deposits of the Tennant Creek district (e.g. Au–Cu–Bi mineralisation; hematite–bornite–chalcocite assemblages), making them a unique and important member of this complex family of deposits. Mafic–intermediate sills below Starra ore deposits indicate a potential link between magmatic activity and IOCG mineralisation. Mushketovite associated with chalcopyrite mineralisation indicates that the mineralising fluid was initially reduced. Different radiogenic Pb isotope compositions in Cu sulfides, hematite and calcite require multiple Pb sources, which is consistent with distinct fluids. [ABSTRACT FROM AUTHOR]

The excessive use of pesticides has led to the harmful contamination of water reservoirs. Visible-light-driven photocatalysis is one of the suitable methods for the removal of pesticides from water. Herein, the development of CBO (Co3O4-Bi2O3) as a heterogeneous catalyst for the visible light-assisted degradation of Fipronil and Acetochlor pesticides is reported. After synthesis via coprecipitation using cobalt (II) nitrate hexahydrate (Co(NO3)2·6H2O), bismuth (III) nitrate pentahydrate (Bi(NO3)3·5H2O) and sodium hydroxide (NaOH) as precursor materials, the prepared CBO was characterized using advanced techniques including XRD, EDS, TEM, SEM, FTIR, and surface area and pore size analysis. Then, it was employed as a photocatalyst for the degradation of Fipronil and Acetochlor pesticides under visible light irradiation. The complete removal of Fipronil and Acetochlor pesticides was observed over CBO photocatalyst using 50 mL (100 mg/L) of each pesticide separately within 120 min of reaction. The reaction kinetics was investigated using a non-linear method of analysis using the Solver add-in. The prepared CBO exhibited a 2.8-fold and 2-fold catalytic performance in the photodegradation of selected pesticides than Co3O4 and Bi2O3 did, respectively. [ABSTRACT FROM AUTHOR]

Thermoelectric materials have been widely recognized as a simple approach to harness green energy by converting thermal gradients into electrical energy. However, the intricate interplay between electrical conductivity, Seebeck coefficient, and thermal conductivity in thermoelectric materials presents a challenge to improving their efficiency. Traditional experimental methods and calculation methods have troublesome steps and long cycles for predicting new thermoelectric materials. In this work we present materials informatics-based approach, where statistical and machine learning models like correlation matrix, multiple linear regression, principal component analysis and artificial neural network were employed to find the relationship between features and thermoelectric performance. Furthermore, artificial neural network was used to analyze the roles of several compositional and microstructural features along with temperature on electrical conductivity, thermal conductivity, Seebeck coefficient and thermoelectric figure of merit (ZT) for PANI and quasi 0D carbon-based composites. [ABSTRACT FROM AUTHOR]

Lead-free bismuth-based perovskite halides are promising materials for optoelectronic applications owing to their lower toxicity, high absorption coefficient, and similar isoelectronic structure to (lead) Pb. Herein, we report the synthesis of Cs3Bi2Br9 perovskite quantum dots (QD) via a modified LARP method and have studied the structural and optical properties. In this study, the QD exhibits an interesting dual emission peak and a bright, unique cyan-green luminescence, with an improved photoluminescence quantum yield of 34%. Studies on Cs3Bi2Br9 QD have been reported earlier, but interestingly the origin of optical properties remains disputed and varies significantly from literature to literature. As a result of our analysis, we expect observed photoluminescence to arise from interconfigurational electronic transitions of Bi3+ ions, with an intense peak at 476 nm attributed to A-band emission and a broad emission at 498 nm attributed to emission from a lower energy level in bismuth ion. Hence, these QDs are suitable for various optoelectronic applications, such as light-emitting diodes (LEDs). [ABSTRACT FROM AUTHOR]

Thermoelectrics are critical for sustainable energy development because they allow for the direct conversion of waste heat into electricity, improve energy efficiency in a variety of applications, and provide a clean, dependable, and maintenance- free alternative for power generation. In recent days, metal chalcogenides have gained more attention in the field of thermoelectrics. Among the chalcogenide materials, Tin Selenide is a promising material for mid-temperature thermoelectric applications, whereas Bismuth Telluride is mainly known for its room-temperature thermoelectric applications. The combination of these two materials would probably enhance the performance of the thermoelectric generator. The present work deals with bilayer and multilayer thin film deposition of Tin Selenide and Bismuth Telluride on the glass substrates by physical vapor deposition. Then the deposited thin films were given a post-annealing treatment for 30 minutes at 323 K, 423 K, and 523 K. The structure and morphology of the thin films have been studied using X-Ray Diffraction (XRD), Scanning Electron Microscopy(SEM), Field Emission Scanning Electron Microscopy(FESEM) and Atomic Force Microscopy (AFM). The Seebeck Coefficient and Electrical conductivity of the bilayer and multilayer thin films were studied using the Seebeck Coefficient measurement system as temperature as function in a range of 300K to 573 K. The maximum Seebeck Coefficent of -350μV/K was obtained for both bilayer and multilayer thin film at 573 K. The highest electrical conductivity of 220S/m and 170S/m were obtained for bilayer and multilayer thin film respectively. The power factor that gives the thermoelectric generator's performance was calculated from the Seebeck Coefficient and Electrical conductivity. The overall power factor for 573 K annealed films of bilayer and multilayer thin films increases with rise in temperature. The maximum obtained power factor for bilayer and multilayer thin films were 25W/K2m and 18 W/K2m respectively. An increase in the annealing temperature leads to improved thermoelectric performance for both bilayer and multilayer thin films. [ABSTRACT FROM AUTHOR]

Earth-adequate quaternary chalcogenides like Cu2NiSnS4 with more complex crystal structures can become non-toxic and cost-effective thermoelectric (TE) materials. TE materials, by employing the energy filtering effect through appropriate energy bandgap, have enhanced their TE efficiency. The composition of CuO in Cu2NiSnS4 matrix has enhanced the Seebeck coefficient (S) and declined the thermal conductivity (κ) simultaneously, due to the decrement of carrier concentration (n), by increasing the wt% of CuO in the composites. The highest power factor of 270.88 μW m−1 K−2 at 573 K is recorded for 30 wt% composites. The 30 wt% composite material thermal conductivity exhibited a low value of 0.442 W m−1 K−1 through stronger phonon scattering at the interface boundaries formed between the Cu2NiSnS4 matrix and CuO compositions. A maximum zT of 0.35 for the Cu2NiSnS4/30 wt% CuO composite was obtained, 75% larger than that of the Cu2NiSnS4 matrix at 573 K. This strategy of introducing metal oxides into the metal sulphide matrix for obtaining efficient TE performance could be extended to other eco-friendly quaternary chalcogenides. [ABSTRACT FROM AUTHOR]

Ethylene glycol electrooxidation catalyzed by Pd nanoparticles was found to be largely improved by Bi2Te3 nanosheets both in the dark and under visible light irradiation. [ABSTRACT FROM AUTHOR]