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Development of effective antimicrobial wound dressings has drawn wide attention in the wound care market. Here, we synthesized a natural antibiotic (aloe-emodin, AE) and a carbon nanoparticle coembedded polymer hybrid hydrogel as a novel wound dressing in the fight against potent skin infections. We systematically evaluated the properties of the obtained hydrogels, including physico-chemical characteristics, photothermal conversion efficiency, reactive oxygen species (ROS) generation, AE-released profile, antibacterial activity, and wound-healing capability. The hybrid gels can initially reduce the number of bacteria in a short time through the near-infrared-light (NIR) triggered photothermal/ROS route and continuously kill the remaining live cells by releasing AE from gels after turning off the NIR source with a long-term antibacterial effect. These two antibacterial mechanisms that complement each other lead to excellent antibacterial performance toward various bacterial strains including multidrug-resistant bacteria. Moreover, in vivo Staphylcoccus aureus-infected animal experiments indicate that the hybrid gels upon NIR irradiation have a striking ability toward wound infection. These studies demonstrate that the AE and carbon nanoparticle coembedded hybrid polymer hydrogels with NIR exposure may have applications in wound combined care for bacterial infections.

The recent advances in solution-synthesized thermoelectric materials with hybrid architectures have been briefly summarized.

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generation efficiency, which is characterized by a dimensionless figure-of-merit ZT of the materials employed. ZT is defined as ZT = S 2 σT/(κ e +κ L ), where S, σ, and T are the Seebeck coefficient, electrical conductivity, and absolute temperature, κ e and κ L are thermal conductivity contributed by charge carriers (either electrons or holes) and phonons, respectively. [2] The thermoelectric properties of chalcogenides with weakly bonded 2D atomic sheets, such as SnSe, [3] SnSe 2 , [4] Cr 2 Ge 2 Te 6 , [5] GeSe, [6] and In 4 Se 3[7] are attracting attention because they show intrinsically low thermal conductivities deriving from the layered structure. CuSbSe 2 is also a similar chalcogenide with a direct bandgap of ≈1.0 eV [8,9] and exhibits potential for thin-film photovoltaic applications. [10,11] As shown in Figure 1a, the CuSbSe 2 crystallizes in an orthorhombic structure with the Pnma space group. This material has 2D double-layered honeycomb-like sheets within the ab plane, which is composed of self-condensed Sb 2 CuSe 3 and SbCu 2 Se 3 six-membered rings. [8] The Cu atom is tetrahedrally coordinated to four Se atoms with three kinds of CuSe bonds, while the Sb atom is coordinated by three Se atoms in a trigonal pyramidal configuration( Figure 1b). The Sb 3+ has lone-pair 5s 2 electrons which are stereochemically expressed in the structure. [12] Such structural features result in giant lattice vibration anharmonicity with a large average Grüneisen parameter γ ave of 1.215, [13,14] which is benifical for low thermal conductivity as found in tetrahedrites, [15,16] AgBiSe 2 , [17,18] CuSbS 2 , [19] and InTe [20] compounds. In addition, the neighboring 2D CuSbSe 2 sheets are interconnected by weaker secondary SbCu and SbSe bonds (pink dotted lines in Figure 1b). [21] The lattice vibration anharmonicity combined with the interlayer weaker bonding leads to low lattice thermal conductivity in the CuSbSe 2 compound, [22] similar to SnSe, [23] AgSbTe 2 , [24] and Cu 3 SbSe 3 . [25] In addition, first-principles density functional theory calculations reveal that the valence bands near the Fermi level of CuSbSe 2 are relatively flat and degenerate at Z point (0, 0, 1/2), which lead to a high effective mass (m*≈ 2.05 m 0 ). [9] Thus, an intrinsically high Seebeck coefficient is also expected in this compound. These attributes as well as the earth-abundant and low-toxic constituent elements make this material worth exploring for This work reports the thermoelectric properties of the CuSbSe 2 -x mol% PtTe 2 (x = 0, 0.5, 1.0, 1.5, and 2.0) pellets composed of highly oriented single crystalline nanoplates. CuSbSe 2 -PtTe 2 single crystalline nanoplates are prepared by a wet-chemical process, and the pellets are prepared through a bottom-up self-assembly of the CuSbSe 2 -PtTe 2 nanoplates and spark plasma sintering (SPS) process. X-ray diffraction and field emission scanning electron microscopic analyses show a highly textured nature with an orientation factor of ≈0.8 for (00l) facets along the primary surface of the p...

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This experimental study reveals intriguing thermoelectric effects and devices in epitaxial bismuthene, two-dimensional (2D) bismuth with thickness ⩽30 nm, on Si (111). Bismuthene exhibits interesting anisotropic Seebeck coefficients varying 2–5 times along different crystal orientations, implying the existence of a puckered atomic structure like black phosphorus. An absolute value of Seebeck coefficient up to 237 μV K−1 sets a record for elemental Bi ever measured to the best of our knowledge. Electrical conductivity of bismuthene can reach up to 4.6 × 104 S m−1, which is sensitive to thickness and magnetic field. Along with a desired low thermal conductivity ∼1.97 W m−1 K that is 20% of its bulk form, the first experimental zT value at room temperature for bismuthene was measured ∼10–2, which is much higher than many other VA Xenes and comparable to its bulk compounds. Above results suggest a mixed buckled and puckered Bi atomic structure for epitaxial 2D bismuth on Si (111). Our work paves the way to explore potential applications, such as heat flux sensor, energy converting devices and so on for bismuthene.