Between the sheets: Sodium‐ion batteries are an attractive, low‐cost alternative to lithium‐ion batteries. Nitrogen‐doped porous carbon sheets are prepared by chemical activation of ...polypyrrole‐functionalized graphene sheets. When using the sheets as anode material in sodium‐ion batteries, their unique compositional and structural features result in high reversible capacity, good cycling stability, and high rate capability.
As an extended member of the thermoelectric family, ionic thermoelectrics (i‐TEs) exhibit exceptional Seebeck coefficients and applicable power factors, and as a result have triggered intensive ...interest as a promising energy conversion technique to harvest and exploit low‐grade waste heat (<130 °C). The last decade has witnessed great progress in i‐TE materials and devices; however, there are ongoing disputes about the inherent fundamentals and working mechanisms of i‐TEs, and a comprehensive overview of this field is required urgently. In this review, the prominent i‐TE effects, which set the ground for i‐TE materials, or more precisely, thermo‐electrochemical systems, are first elaborated. Then, TE performance, capacitance capability, and mechanical properties of such system‐based i‐TE materials, followed by a critical discussion on how to manipulate these factors toward a higher figure‐of‐merit, are examined. After that, the prevalent molding methods for assembling i‐TE materials into applicable devices are summarized. To conclude, several evaluation criteria for i‐TE devices are proposed to quantitatively illustrate the promise of practical applications. It is therefore clarified that, if the recent trend of developing i‐TEs can continue, the waste heat recycling landscape will be significantly altered.
In this review, the progress in ionic thermoelectrics, including fundamental theories, material designations, property characteristics, performance regulations, molding methodologies, and device employments, are comprehensively summarized. Perspective remarks on the outlook and challenges of ionic thermoelectrics are also discussed.
Driven by the intensive efforts in the development of high‐performance GeTe thermoelectrics for mass‐market application in power generation and refrigeration, GeTe‐based materials display a high ...figure of merit of >2.0 and an energy conversion efficiency beyond 10%. However, a comprehensive review on GeTe, from fundamentals to devices, is still needed. In this regard, the latest progress on the state‐of‐the‐art GeTe is timely reviewed. The phase transition, intrinsic high carrier concentration, and multiple band edges of GeTe are fundamentally analyzed from the perspectives of the native atomic orbital, chemical bonding, and lattice defects. Then, the fabrication methods are summarized with a focus on large‐scale production. Afterward, the strategies for enhancing electronic transports of GeTe by energy filtering effect, resonance doping, band convergence, and Rashba band splitting, and the methods for strengthening phonon scatterings via nanoprecipitates, planar vacancies, and superlattices, are comprehensively reviewed. Besides, the device assembly and performance are highlighted. In the end, future research directions are concluded and proposed, which enlighten the development of broader thermoelectric materials.
The phase transition, multiple valence bands, and resonant bonding endow GeTe with promising thermoelectric performance. Significant breakthroughs are achieved in GeTe‐based materials. This review summarizes the recent progress in developing high‐performance GeTe‐based materials and devices, including the underlying fundamentals, large‐scale production, novel strategies for boosting performance, and techniques of device assembly.
Organic tailored materials using various aromatic carbonyl derivative polyimides are synthesized by tuning the alteration of the conjugated backbone. These materials are used as the cathodes for ...high‐power, long‐cycle, and sustainable sodium‐organic batteries.
Five new zero-dimensional hybrid manganese halides based on discrete MnCl
4
2−
tetrahedrons were prepared and used as highly efficient green-light emitters. Through rational management of organic ...cations to tailor the Mn Mn separation distances between neighboring MnCl
4
2−
tetrahedrons, the photoluminescence quantum yield increased significantly from 7.98% to 81.11%.
Five new zero-dimensional hybrid manganese halides based on discrete MnCl
4
2−
tetrahedrons were prepared and used as highly efficient green-light emitters.
SnSe is challenging to use in thermoelectric devices due to difficulties in simultaneously optimizing its thermoelectric and mechanical properties. Here, the authors show a unique solvothermal ...synthetic environmental design to fabricate super‐large and micro/nanoporous Sn0.965Se microplates by using CrCl3. Cl− ions to trigger Sn‐vacancy formation and optimize the hole concentration to ≈3 × 1019 cm−3, while the as‐formed Cr(OH)3 colloidal precipitations act as “templates” to achieve micro/nanoporous features, leading to low lattice thermal conductivity of ≈0.2 W m−1 K−1 in the as‐sintered polycrystal, contributing to a high ZT of ≈2.4 at 823 K and an average ZT of ≈1.1. Of particular note, the polycrystal exhibits high hardness (≈2.26 GPa) and compression strength (≈109 MPa), strengthened by grain refinement and vacancy‐induced lattice distortions and dislocations; while a single‐leg device provides a stable output power (>100 mW) and conversion efficiency of ≈10% by a temperature difference of 425 K, indicating great potential for applying to practical thermoelectric devices.
A solvothermal synthetic environmental design to fabricate super‐large and micro/nanoporous Sn0.965Se microplates using CrCl3 is employed, and the mechanically robust polycrystals sintered from these microplates exhibit a high ZT of ≈2.4 at 823 K and an average ZT of ≈1.1, leading to a conversion efficiency of ≈10% by a temperature difference of 425 K in the single‐leg device.
Summary
Membrane vesicles (MVs) released from bacteria act as extracellular vehicles carrying various functional cargoes between cells. MVs with different cargoes play multiple roles in stress ...adaptation, nutrient acquisition and microbial interactions. However, previous studies have primarily focused on MVs from Gram‐negative bacteria, while the characteristics of cargoes in MVs from Gram‐positive bacteria and their involvement in microbial interactions remain to be elucidated. Here, we used a Gram‐positive strain, Dietzia sp. DQ12‐45‐1b from Corynebacteriales, to analyse the characteristics and functions of MVs. We identified the ‘antioxidant’ canthaxanthin is stored within MVs by LC–MS/MS. In addition, nearly the entire genomic content of strain DQ12‐45‐1b are evenly distributed in MVs, suggesting that MVs from DQ12‐45‐1b might involve in horizontal gene transfer. Finally, the mycobactin‐type siderophores were detected in MVs. The iron‐loaded MVs effectively mediate iron binding and delivery to homologous bacteria from the order Corynebacteriales, but not to more distantly related species from the orders Pseudomonadales, Bacillales and Enterobacterales. These results revealed that the iron‐loaded MVs are shared between homologous species. Together, we report the Gram‐positive bacterium Dietzia sp. DQ12‐45‐1b released MVs that contain canthaxanthin, DNA and siderophores and prove that MVs act as public goods between closely related species.
Arrays of aligned porous CuO nanorods are obtained by a facile and scalable method of engraving Cu foil in situ. Direct use of the arrays as a flexible and binder‐free sodium‐ion battery anode — ...without adding auxiliary materials — results in superior electrochemical performance, including cycle stability and rate capability, even at room temperature. This can be attributed to the unique array structure and the lack of binder in the electrode.
Microbes spontaneously release membrane vesicles (MVs), which play roles in nutrient acquisition and microbial interactions. Iron is indispensable for microbes, but is a difficult nutrient to ...acquire. However, whether MVs are also responsible for efficient iron uptake and therefore involved in microbial interaction remains to be elucidated. Here, we used a Gram-positive strain, Dietzia sp. DQ12-45-1b, to analyze the function of its MVs in heme-iron recycling and sharing between species. We determined the structure and constituent of MVs and showed that DQ12-45-1b releases MVs originating from the mycomembrane. When comparing proteomes of MVs between iron-limiting and iron-rich conditions, we found that under iron-limiting conditions, heme-binding proteins are enriched. Next, we proved that MVs participate in extracellular heme capture and transport, especially in heme recycling from environmental hemoproteins. Finally, we found that the heme carried in MVs is utilized by multiple species, and we further verified that membrane fusion efficiency and species evolutionary distance determine heme delivery. Together, our findings strongly suggest that MVs act as a newly identified pathway for heme recycling, and represent a public good shared between phylogenetically closely related species.
Glutamate is a biomarker for many nervous system diseases, and sensitively detecting glutamate is meaningful in the clinic. Therefore, a unique 3D framework of Cd-MOF (1) is synthesized and ...characterized. A single-crystal X-ray study reveals that it is a two-fold interpenetration (4,4)-connected framework with a PtS topology, where a large 1D rhombic channel with a size of 8 × 14 Å exists and the total potential void volume can reach 62%. Luminescence results demonstrate that 1 has good luminescence stability and can sensitively detect glutamate in water with a detection limit of 1.15 × 10–7 mol/L, which makes it the most sensitive MOF-based luminescence sensor of glutamate to date. More importantly, it also can serve as a luminescence sensor to detect glutamate in serum, and the quenching concentration needs to be only 43.1 μmol/L, which is much lower than the harmful level of glutamate (400 μmol/L) in glioma patients’ blood. Compound 1 can be used at least five cycles. These results show that 1 has a potential application in monitoring glutamate in clinical scenarios.
PDF
