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This study reports the employment of Co(OH)xF2−x nanosheets, a new material in the sensor field, for gas sensor applications. We synthesize Co(OH)xF2−x nanosheets via a hydrothermal route using SiO2 sphere templates. Our material characterization confirms that the material is a densely clustered Co(OH)xF2−x nanosheet with an amorphous microstructure with some short-range ordering. Sensors based on the nanosheets demonstrate a high response of 269% toward 4.5 ppm of acetone gas at an operation temperature of 200 °C and a very low minimum detection limit of 40 ppb. It functions effectively up to a temperature below 300 °C, above which F is found to start to evaporate. Our discussion suggests that an excellent sensor performance arises from the high catalytic function of F incorporated in a high concentration in the material as well as the high specific surface area due to the morphology of densely clustered nanosheets. [ABSTRACT FROM AUTHOR]

Heat removal via thermal management materials is attracting more and more attention in the electronic industry. Conventional particle/polymer thermal conductive composites require a high filler loading ratio (>30 vol %), which cause severe thermal interfacial resistance and mechanical issue. In this work, we fabricate tellurium nanowires (NWs)/epoxy nanocomposites via a facile bar coating method. According to Agari model and Maxwell–Eucken model, the as‐synthesized ultra‐long NWs with high aspect ratio (>100) construct the 3D interconnected thermal conductive network better in resin matrix to facilitate the heat transfer process. The results show that at a low loading ratio of 2.4 vol %, this nanocomposite exhibits the out‐of‐plane and in‐plane thermal conductivity of 0.378 and 1.63 W m−1 K−1, respectively, which is 189 and 715% higher than that of pure epoxy resin. Importantly, good stability, and flexibility of nanocomposites are well maintained. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47054. Low loading of Te nanowires based epoxy nanocomposites with high thermal conductivity for thermal interface materials application [ABSTRACT FROM AUTHOR]

Flexible thermoelectric materials that enable harvesting electricity from human body heat or an ambient temperature gradient have potential applications in self‐powered flexible wearable electronics. The development of more efficient and flexible n‐type thermoelectric materials, however, is highly desired but challenging. Herein, reported is a nylon substrate supported fabric silver telluride (Ag2Te) nanowire network used as flexible n‐type thermoelectric materials, by the combination of vacuum filtrated assembly and mechanical pressing method. The prepared silver telluride nanowire films show optimal thermoelectric properties with the Seebeck coefficient of −129.5 µV K−1 and electrical conductivity of 187.78 S cm−1, leading to the highest power factor of 315.1 µW m−1 K2. Owing to the elimination of Peierls stress in the fabrics interlocking structure, the silver telluride nanowire films exhibit good flexibility, as the thermoelectric properties only have a change below 10% after 500 bending cycles. Based on the silver telluride nanowire film, a flexible self‐powered temperature sensor is fabricated for detecting the temperature from a human finger. The sensor shows high sensitivity that its response time and reset time are about 1.05 and 2.1 s, respectively. The results imply that silver telluride nanowire films have great potential applications in flexible thermoelectric energy conversion and self‐powered temperature sensing. Flexible and high‐performance n‐type thermoelectric films consisting of unique interlocking silver telluride nanowires are presented through vacuum filtrated assembly and mechanical pressing methods. The films possess a power factor as high as 315.1 µW m−1 K2 at 410 K. A self‐powered temperature sensor with high sensitivity is fabricated for detecting the temperature from a human finger. [ABSTRACT FROM AUTHOR]

Ever‐increasing packaging and power densities of modern electronic devices in the present "More‐than‐Moore" technology era demand higher performance thermal interface materials (TIMs). However, conventional composite TIMs require higher loading to achieve better thermal conductive property, resulting in a mechanical problem. The poor wetting property of matrix loading materials further increases the interfacial thermal resistance (ITR). In this work, a one‐step hydrothermal method is employed to grow 2D molybdenum disulfide (MoS2) nanosheets on a tellurium (Te) nanowire skeleton and silver (Ag) nanoparticles are further decorated on MoS2 nanosheets via the photoreduction method. The in‐plane thermal conductivity of the final nanocomposite reaches as high as 10.4 W m−1 K−1, which is 4,160% higher than that of a pure epoxy resin and one order of magnitude higher than that of conventional polymeric nanocomposites. The 3D interconnected heat transferring network of Te/MoS2/Ag greatly enhances the thermal stability of the composite in practical applications. The rational materials design concept may contribute to the development of new types of high‐performance thermal management materials. A Te/MoS2/Ag‐epoxy composite film shows impressive thermal conductivity of 10.4 W m−1 K−1 which is 4.160% higher than that of pure epoxy. MoS2 nanosheets with good adhesion property chemically connect nanofiller with epoxy resin matrix, which leads to a highly depressed interfacial thermal resistance. [ABSTRACT FROM AUTHOR]

N2 fixation is one of the most important chemical reactions in the ecosystem of our planet. However, the industrial Haber-Bosch ammonia synthesis process is restricted by harsh reaction conditions (350-550 °C, 150-350 atm) and undesirable environmental effects (a large amount of CO2 emission). Photocatalytic N2 fixation is promising for achieving sustainable ammonia synthesis under ambient conditions with lower energy input and less environmental issues. However, the known photocatalysts for N2 reduction under mild conditions still face the great challenge of very low energy conversion efficiency. Herein, we report a facile solution-phase method to prepare the heterojunctions based on n-type Bi2MoO6 nanorods and oxygen-vacancy-rich p-type BiOBr nanosheets (Bi2MoO6/OV-BiOBr). Originating from the formation of p-n junctions and suitable bandgap configuration, the Bi2MoO6/OV-BiOBr heterojunctions exhibit effective light utilization and photogenerated electron-hole separation properties. Moreover, it is confirmed that the oxygen vacancies on BiOBr nanosheets are propitious to the adsorption and activation of N2 molecules. Benefiting from these merits, the Bi2MoO6/OV-BiOBr heterojunctions exhibit improved photocatalytic performance for N2 conversion to ammonia without any noble metal co-catalysts and sacrificial reagents under ambient conditions.