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Limited by the relatively low adsorption capacity of inorganic nanomaterials for antibiotics , ultralong hydrogen titanate nanobelts (UHTNs) with a hollow structure and high surface area (442.21 m2 g−1) were synthesized to evaluate the feasibility as a potential adsorbent material for antibiotic removal. A batch of adsorption experiments were conducted by using norfloxacin (NFO), tetracycline (TC) and ofloxacin (OFO) as the model antibiotic molecules. The results indicate that the adsorption of antibiotics on UHTNs is better fitted to the pseudo-second-order kinetic model, and the UHTNs' maximum adsorption capacities calculated from the Langmuir isotherm model were 151.51 mg g−1 for TC, 111.73 mg g−1 for NFO, and 148.14 mg g−1 for OFO at pH = 7, which are far better than those of most reported inorganic adsorbent materials. In the adsorption process of tetracycline, the surface complexation between the adsorbent and TC contributed most to the adsorption; this has been elucidated by Fourier Transform Infrared (FT-IR) spectroscopy and X-ray photoelectron spectroscopy (XPS). In addition, because the UHTNs are up to tens of micrometers in length, they can be easily aggregated to form a network. Therefore, a novel paper-like, free-standing UHTN membrane was fabricated via a simple vacuum filtration method, which also exhibits good adsorption capacity.

Doping is an effective way to optimize the performance of thermoelectric materials. In order to investigate the effect of Bi doping on microstructures and thermoelectric properties of Ge0.90Pb0.10Te, a series of Ge0.90−xPb0.10BixTe compounds were prepared by a melting-quenching-annealing process followed by spark plasma sintering. The Bi doping on Ge site acts as an electron donor, which effectively optimized the carrier concentration from 1.1 × 1021 cm−3 to 3.5 × 1020 cm−3. Besides, the lattice distortions originated from Bi doping further promoted the solubility of Pb in the GeTe matrix, which have great advantage for obtaining lower thermal conductivity compared with pristine Ge0.90Pb0.10Te sample. Low lattice thermal conductivity of about 0.77 W/mK was obtained in Ge0.86Pb0.10Bi0.04Te owing to the additional lattice defects introduced by Bi doping. Consequently, the highest ZT of 1.1 was obtained in Ge0.86Pb0.10Bi0.04Te at 600 K with an average ZT of 0.6. These results have confirmed that Bi doing is an efficient way to boost the thermoelectric performance of GeTe-based alloys.

A facile method to synthesize isomorphous MnO2@MnO2 core/shell nanostructures was developed for the first time by using MnO2 nanowires as seed crystals. These unique nanoarchitectures consisting of an isomorphous layer of β-MnO2 nanosheets well grown on the surface of β-MnO2 nanowires exhibit remarkable electrochemical performance with high capacitance and ultra long cycle life, i.e., nearly 92.2% retention after 20 000 cycles at a current density of 5 A g−1. The enhanced specific capacitance of the MnO2@MnO2 electrode is largely contributed by the capacitive processes including double-layer charging and Faradaic pseudocapacity. Particularly, these intriguing behaviors are strongly correlated with the unique isomorphous core/shell hierarchical configuration and high mechanical stability as well as the better interfacial structures between the MnO2 nanowire core and the ultrathin MnO2 nanosheet shell. In addition, it is demonstrated that the formation of defective and disordered regions throughout the whole core/shell architecture is the main cause for the unusual increased capacity during the early stages of cyclic charge/discharge.

International audience; Polymer composites with enhanced mechanical and functional properties are highly desired to develop light-weight function-integrated structures and devices. In this study, one kind of urchin-like hybrids was synthesized by in-situ growing CNTs on alumina microspheres (μAl2O3), and their reinforcing effects to epoxy were investigated in detail. It was found that as compared to pure epoxy the CNTs-μAl2O3 hybrids/epoxy composites possess highly improved electrical, dielectric, thermal and mechanical properties, achieving an enhancement as high as 5 orders of magnitude in the AC conductivity, 92% and 56% in the thermal diffusivity and thermal conductivity, respectively, and 26% in the Young’s modulus, when CNT mass fraction used was 2%. Detailed analyses and various microstructural characterizations were also conducted in order to understand the multiscale reinforcement effects. The significant enhancements observed are mainly due to the urchin-like structure and improved CNT dispersion in the epoxy matrix.

Ferritic steels containing copper have been studied as model systems for clusters/precipitate formation in reactor pressure vessel steels. The samples were aged at 400 °C for 4000 h and subsequently cold rolled to 30% reduction at room temperature. The microstructural characteristics of the samples were analyzed using high-resolution transmission electron microscopy. Direct evidence was found that the fivefold twinning occurs via simultaneous emission of two Shockley partial dislocations from two particular α-Fe/Cu interfaces, and then the pileup tips of the twofold twin.

We have reported a facile, template-free and effective electrochemical method to grow MnO2 ultrafine nanobelts on Ni foam. Electrochemical measurements showed that the MnO2 nanobelt electrode exhibited an enhanced specific capacitance of 509 F g−1 at 200 mA g−1 at 50 °C. More importantly, the specific capacitance of the MnO2 nanobelt electrode nearly has 91.3% retention after 5000 cycles with repeated heating and cooling in the temperature range of 0 to 50 °C, showing good high temperature-resistive long-term cycle stability.

Porous urchin-like MnCo2O4.5 hierarchical architectures (~4–6 μm in diameter) synthesized by a facile hydrothermal route followed by a calcination process exhibited a specific capacitance of 151.2 F g−1 at 5 mV s−1, outstanding rate capability with 83.6% specific capacitance retention even when the current density is increased 50 times and excellent long-term cycle stability at progressively varied current densities and could be considered as a potential mixed transition metal oxide material for high-rate supercapacitors in some special applications that do not require a high capacitance.

An effective magnetic-field-assisted hydrothermal synthesis was used to induce the growth of 2 × 2 tunnel MnO2 nanostructures for supercapacitor application. The as-fabricated electrode from the MnO2 nanostructures exhibited an enhanced specific capacitance of 306 F g−1 at 0.5 A g−1 and desirable cyclic stability, which considerably exceed the performance of MnO2 material prepared with and without a high magnetic field, making it a promising electrode material for supercapacitors.

Al and Ti doped ZnO thin films have been prepared by direct current magnetron cosputtering and thermal oxidation. The effects of these dopants on the microstructural, morphological and electrical properties of deposited films have been studied. The SEM demonstrated that the undoped ZnO thin film consisted of globular ZnO with particle size of ∼100 nm. Scanning electron microscopy EDX analysis confirmed that the dopant content in the ZnO–Al and ZnO–Ti thin film was 2·78 and 3·75 at-% respectively. The particle in the ZnO–Ti thin film was blocky or granular with thorns and its size was several micrometers, while the particle in ZnO–Al thin film was porous granular and the size was ∼2 μm. Resistance value testing and R/R calculation revealed that pure ZnO thin film had the highest gas sensitivity.