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Zintl compounds such as n‐type Mg3(Sb,Bi)2 show promising thermoelectric applications benefiting from their high valley degeneracy and low lattice thermal conductivity. However, the heavier p‐type AMg2X2 (A = Ca, and Yb; X = Bi and Sb) Zintl counterparts even exhibit a higher κlat due to strong chemical bonding. Reducing κlat of AMg2X2 is an important route for improving thermoelectric performance. Herein, it is found that Cd doping at the Mg site in CaMg2Bi2 can weaken intralayer covalent bonds and soften acoustic phonons, as well as fill the optical phonon gap. These effects result in large atomic displacement, low phonon group velocity, and strong lattice vibration anharmonicity. Doping 10% Cd leads to a reduction of 56% in the κlat of CaMg2Bi2. Moreover, Cd doping promotes orbital alignment and thus increases the density‐of‐states effective mass and Seebeck coefficient. Eventually, in conjunction with carrier concentration optimization by Na doping and band structure engineering by Ba doping, a high ZT of ≈1.3 at 873 K in (Ca0.85Ba0.15)0.995Na0.005Mg1.85Cd0.15Bi2 sample is realized. This work highlights the significant role of manipulating chemical bonding in suppressing phonon propagation of semiconductors. [ABSTRACT FROM AUTHOR]

Diabetic wound microenvironment has extremely complex continuous hyperglycemia, hypoxia, bacterial infection, and reactive oxygen species accumulation, which lead to slow wound healing. In order to overcome these limitations, glucose oxidase (GOX) and catalase (CAT) were loaded into zinc sulfide (ZnS) particle spheres to construct a high glucose microenvironment responsive treatment strategy with good biocompatibility. When they encounter hyperglycemia and oxidative wound microenvironment at the wound site, the presence of GOX and CAT will be activated by glucose to undergo an effective local cascade catalytic cycle reaction, which decomposes glucose and H2O2 into gluconic acid and O2. They not only reduce the toxic side effects of GOX, improve the hyperglycaemic wound microenvironment, lower the local pH, maintain, and alleviate O2 depletion problems but also trigger the ZnS particle spheres to convert the high glucose microenvironment, which is not conducive to tissue and cell survival, into a favorable environment (zinc gluconate and H2S gas). These products can not only synergistically accelerate cell migration and proliferation in a high glucose environment and play a role in starvation and inhibition of killing bacteria but also enhance the activity of enzyme proteins and achieve long-term effective treatment. [ABSTRACT FROM AUTHOR]

The crystal phase, alongside the composition, morphology, architecture, facet, size, and dimensionality, has been recognized as a critical factor influencing the properties of noble metal nanomaterials in various applications. In particular, unconventional crystal phases can potentially enable fascinating properties in noble metal nanomaterials. Recent years have witnessed notable advances in the phase engineering of nanomaterials (PEN). Within the accessible strategies for phase engineering, the effect of strain cannot be ignored because strain can act not only as the driving force of phase transition but also as the origin of the diverse physicochemical properties of the unconventional crystal phase. In this review, we highlight the development of unconventional crystal-phase noble metal nanomaterials within strain engineering. We begin with a short introduction of the unconventional crystal phase and strain effect in noble metal nanomaterials. Next, the correlations of the structure and performance of strain-engineered unconventional crystal-phase noble metal nanomaterials in electrocatalysis are highlighted, as well as the phase transitions of noble metal nanomaterials induced by the strain effect. Lastly, the challenges and opportunities within this rapidly developing field (i.e., the strain engineering of unconventional crystal-phase noble metal nanocatalysts) are discussed. [ABSTRACT FROM AUTHOR]

Over the years, Bi2Te3-based alloys have garnered considerable recognition as exceptional thermoelectric materials. Researchers have diligently pursued avenues to enhance the properties of these materials, with a primary focus on reducing thermal conductivity while maintaining optimal electrical performance. Nonetheless, achieving this delicate balance has proven to be a formidable challenge. In this study, we present a novel synergistic optimization approach that entails manipulating the grain refinement and porous structure of the material through precise adjustments in cooling rate and relief temperature during the direct current hot pressing process. By meticulously controlling these parameters, we successfully engineered a multiscale microstructure that effectively promotes phonon scattering. Simultaneously, we optimized carrier concentration. The outcomes of our investigation are truly remarkable, as we attained a peak zT value of approximately 1.23 at 325 K, accompanied by an outstanding average zTave of approximately 1.2 across the temperature range of 300–400 K in the 6.5% porosity-Bi0.35Sb1.65Te3 sample. These findings underscore the efficacy of the multiple synergies employed in our study. Moreover, our research provides a solid foundation for further exploration of complex micro structure modification techniques. [ABSTRACT FROM AUTHOR]

The Bi2Te3 family has been considered a state‐of‐the‐art thermoelectric material for room‐temperature applications for over half a century. However, scarcity of the material Te has been a persistent issue. Recently, the discovery of n‐type Mg3(Bi, Sb)2‐based materials provides new hope for replacing traditional Bi2Te3, but their thermoelectric properties near room temperature still need improvement for application to practical devices. Herein, a competitive figure of merit of ≈0.8 at 300 K and a high power factor greater than 30 µW cm−1 K−2 at 300 K in n‐type Mg3.14Mn0.06Bi1.4Sb0.59Se0.01 is reported, benefiting from the rationally tuned carrier concentration of 2.29×1019 cm−3 at room temperature. Substituting the Mg site with Mn in Mg3.2Bi1.4Sb0.59Se0.01 changes the dominant carrier scattering mechanism from a mixed scattering of acoustic phonons and ionized impurities to acoustic phonon scattering. Mn doping in Mg3.2Bi1.4Sb0.59Se0.01 also enhances the mobility to 180 cm2 V−1 s−1, reduces the thermal conductivity, and significantly increases the quality factor β of the material. The high room temperature thermoelectric performance of n‐type Mn&Se co‐doped Mg3(Bi, Sb)2‐based materials makes them a highly competitive substitute for commercialized n‐type Bi2Te3. [ABSTRACT FROM AUTHOR]