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In this paper, the mechanical properties and the crystallization behaviors of nano-ZnO particle reinforced PET (ZnO/PET) composite were investigated in order to verify the possibility of industrial application of ZnO/PET. The addition of nano-ZnO particle (nZnOp) improves the tensile strength and elongation of PET, which reach their maximums at 2 wt% nZnOp addition. The enhancement of tensile properties of ZnO/PET composite indicates the improvement in the crystallinity of PET because of the constancy in molecular weight of PET with and without nZnOp addition. Whereas the impact strength of PET decreases with the nZnO, addition, except the nZnOp addition around 2 wt%, at which the highest value has been achieved among the pure PET and composites. And according to the DSC and XRD results, 2 wt% ZnO/PET composite has the highest crystallinity and among pure PET and composites. Furthermore, by combining both DSC and XRD results, the nZnOp addition was found effective in increasing the crystallinity of PET matrix as well as possibly capable of changing the crystallization form of PET. 2 wt% ZnO/PET composite could be a promising upgrade of PET due to the considerable improvement in mechanical properties.

In this study, a kind of novel porous 3D multi-edges cube SnO2/ZnO composite with n-n heterojunctions was prepared through a facile hydrothermal route. A kind of ordered mesoporous ZnO must be used as precursor in the hydrothermal reaction which was fabricated by soft-template method. The surfaces of the 3D multi-edges cube SnO2/ZnO composite were distributed with ordered mesoporous of 10.2 nm. The grain refinement effect was happen by SnO2, it led to the specific surface area of the material reached to 135.641 $\text{m}^{\textsf {2}}\cdot \text{g}^{\textsf {-1}}$ , which was nearly 3.9 times of ZnO matrix. At room temperature (25°), the 3D multi-edges cube SnO2/ZnO nanomaterial showed excellent gas response to NOx, whose response to 100 ppm NOx reached 60.41±0.5%, the response time was only 2 s, and the detection limit was 0.2 ppm. It broke the tradition that SnO2/ZnO composite showed gas response to NOx only in relatively high temperatures. [ABSTRACT FROM AUTHOR]

Abstract: A kind of novel n–n combined ordered mesoporous WO3/ZnO (OM‐WO3/ZnO) sensor are successfully fabricated in this study. A soft‐template method is used to synthesize the ordered mesoporous ZnO matrix. Surfaces of the ZnO matrix are innovatively modified using silane coupling agent (mark as: OM‐ZnO‐Si), and then a layer of WO3 film is assembled on the surfaces of the OM‐ZnO‐Si by chemical plating method for the first time, and the OM‐WO3/ZnO material is obtained. The prepared OM‐WO3/ZnO sample shows a kind of regular hexagon‐sheet structure. The prepared OM‐WO3/ZnO sensor shows the much better response, much shorter response time, much lower detection limit, and the more excellent selectivity toward NOx gas. When oxynitride (NOx) gas concentration is 100 ppm, the response reaches to 82.64%, the response time is only 6 s at room temperature. The detection limit is only 0.01 ppm. The unique loose porous structure and the synergistic effect of the n–n heterojunction structure endow the prepared OM‐WO3/ZnO material with the superior gas sensing properties. The n–n combined OM‐WO3/ZnO material shows the vast development potential in gas sensor field. [ABSTRACT FROM AUTHOR]

Abstract: The thermoelectric properties of tungsten trioxide (WO3) ceramics doped with zinc oxide (ZnO) were investigated from 473 to 973K. The results revealed that doping WO3 with ZnO could promote the grain growth and the densification. Moreover, the addition of ZnO into WO3 obviously raised the electrical conductivity (σ) of the ceramics by about two orders of magnitude with only slightly decreasing its absolute value of the Seebeck coefficient (|s|). Thus, the magnitude of the power factor (σs 2) was enhanced tremendously by adding ZnO. In addition, there was a second phase (ZnWO4) segregation at the grain boundaries in the samples containing more than 0.5mol% ZnO, which inhibited the further grain growth and reduced the σ and |s|. Therefore, there existed an optimum doping concentration of ZnO in WO3 for obtaining a better power factor. [Copyright &y& Elsevier]

Abstract: Large scale densely packed and vertically oriented ZnO nanorod arrays were grown on F-doped SnO2 (FTO) substrates through a simple hydrothermal synthesis route. Based on the arrays of hexagonal ZnO nanorod with size of 60∼100nm in diameter, and ∼1.5μm in length, a prototypical photoelectrical device was fabricated for ultraviolet detection, showing good reproducibility and a large photocurrent of around 6.71mA at the applied voltage of 0.4V. The large photocurrent and the ohmic I–V characteristics of the ZnO nanorods under the illumination could be ascribed to the decrease of the barrier height among the ZnO nanorods and the Schottky barrier between the nanorods and the Au electrodes and, in particular, to the accumulation of conduction electrons, resulted from the neutralization between photogenerated holes and negatively charged oxygen ions. The photoresponse curve is well fitted to an exponential curve with the relaxation time constant of 9s in rising edge and 90s in decaying one, representing the accumulation of conduction electrons. These well-aligned ZnO nanostructures of high quality could be easily fabricated by a cost-effective chemical route and used for constructing nanoscale devices with excellent performances. [Copyright &y& Elsevier]

In this study, different techniques were used to synthesize the Eu 2 O 3 –ZnO/(SBA-15) composite materials in high temperature, and the luminescent characteristics of prepared materials were studied. The results showed that the frameworks of the prepared materials were kept intact, and their structures were kept highly ordered. The prepared Eu 2 O 3 –ZnO/(SBA-15) materials showed luminescent characteristics. Li + ions doped in ZnO act as the charge compensation and the luminescence sensitizing agent. They enabled the prepared composite materials to show a stronger luminescent phenomenon. The guest materials were distributed in the pores of SBA-15, which shielded them from the external environment. The Eu 2 O 3 –ZnO/(SBA-15) composites exhibited high relative luminescent intensity. [ABSTRACT FROM AUTHOR]

Abstract A kind of chrysanthemum-like ordered mesoporous Eu3+/ZnO luminescent material was synthesized by a hydrothermal method. In prepared process, an ordered mesoporous zinc oxide (OMZ) precursor must be synthesized which was prepared by soft template method, and the sulfosalicylic acid must be used as organic ligands. The prepared Eu3+/ZnO composite showed a unique chrysanthemum-like morphology whose surfaces were distributed the ordered mesoporous, the average diameter of the chrysanthemum-like particles was about 10 μm, the average width of the petals was about 100 nm, and the average length of the petals was about 3 μm. A strongest emission peak was located at 590 nm when the 394 nm was used as excitation wavelength. A strongest emission peak was located at 417 nm when the 359 nm was used as excitation wavelength. The influences of the Eu3+ concentration, hydrothermal temperature and hydrothermal time were studied, and the relevant parameters were confirmed according to the strongest emissions. [ABSTRACT FROM AUTHOR]

Abstract In this study, a much regular hollow tubular ordered porous structure (Tb3+-Yb3+) SSA/ZnO composite was prepared by hydrothermal method. In the prepared process, an ordered porous zinc oxide was necessarily used as precursor which was prepared by soft template method. The sulfosalicylic acid was used as an organic ligand to provide energy for the energy level transfer of rare earths, which also showed the effect of the structure-directing agent for the structure. Yb3+ acted as a sensitizer which enhanced the luminescent intensity of Tb. Tb3+ was the luminescent center, it also acted a part of the mineralizer which influenced the morphology of samples. The sample showed a special hollow tubular structure which was assembled from many nanoparticles, and there were the ordered pores in the particles. The sample showed the emission peak at 489, 543, 585 and 620 nm, and the highest emission peak located at 543 nm. The optimum doping ratio of Tb3+ and Yb3+ was determined by the difference in fluorescence intensity. The porous ZnO promoted the emission intensity of rare earth ions, and greatly reduced the use of rare earth. Graphical abstract Image 1 Highlights • The ordered porous ZnO was prepared by soft template method. • The composite material had a hollow tubular ordered porous structure. • The porous ZnO was used to improve luminescence characteristics of rare earth. [ABSTRACT FROM AUTHOR]

Abstract According to recent reports, the most of semiconductor gas sensors had the higher operating temperature (from 100 to 300 °C), which caused the decrement of selectivity and restricted its application. In this study, we prepared the ordered porous Cr 2 O 3 /ZnO (OP-Cr 2 O 3 /ZnO) gas sensor materials with p-n heterojunction structure, successfully. Firstly, we synthesized ordered porous zinc oxide matrix by soft template method, and then the surface of the ZnO matrix was modified by silane coupling agent to increase the activity of surface. The Cr 2 O 3 film was assembled to the surface of the modified matrix through ultrasonic chemical plating method, and the ordered porous Cr 2 O 3 /ZnO composite material was obtained. The prepared ordered porous Cr 2 O 3 /ZnO gas sensor showed excellent response and selectivity toward NO x gas at room temperature (25 °C ± 2 °C). When the NO x concentration was 100 ppm, the response could reach to 86.7% and the response time was only 4 s, the detection limit was only 0.05 ppm. The superior gas sensing properties of the OP-Cr 2 O 3 /ZnO could been attributed to the loose, ordered porous structure, the large specific surface area, the catalysis of the Cr 2 O 3 , and the synergistic effect of p-n heterojunction structure. Graphical abstract Unlabelled Image Highlights • Ordered porous zinc oxide matrix was synthesized, whose surface was modified to increase the activity of surface. • The Cr 2 O 3 film was assembled to the surface of the modified porous ZnO matrix through ultrasonic chemical plating method. • The prepared the ordered porous Cr 2 O 3 /ZnO composite material has p-n heterojunction structure. • The ordered porous Cr 2 O 3 /ZnO gas sensor showed excellent response and selectivity toward NO x gas at room temperature. [ABSTRACT FROM AUTHOR]

In this work, the copper decorated C-doped ZnO photocatalyst (Cu/C–ZnO) was prepared from the zinc-based metal organic framework composite (MOF-5). Copper was loaded onto the surface of the C–ZnO by photo-reduction method, and the 10 μm octahedron morphology MOF-5 particles were refined to 77 ± 5 nm. The derived Cu/C–ZnO showed a nanometer-scaled structure, which was beneficial for the visible-light response. Moreover, oxygen vacancy can narrow the band gap of ZnO and increase the electron density in Fermi level by the doping of C, which contributes to the charge transfer and separation. A plasma resonance effect was shown when copper was loaded onto the surface of the C–ZnO. The obtained Cu/C–ZnO photocatalysts showed an excellent photocatalytic hydrogen evolution character in visible-light, and the optimal hydrogen production rate reached to 5.363 mmol/g/h which was about 9663 times higher than that of pure ZnO. Image 1 • C–ZnO with an improved valence band position was obtained by calcination of MOF-5. • Copper was loaded onto the surface of the C–ZnO by photo-reduction method. • The 10 μm octahedron MOF-5 particles were refined to 77 ± 5 nm in Cu/C–ZnO. • The photocatalytic properties were sharply improved by copper cocatalyst. [ABSTRACT FROM AUTHOR]

• The 3D ordered mesoporous ball-flower structures ZnO was fabricated by hydrothermal method. • The pure ZnO nanomaterial showed excellent gas response property to NOx at room temperature. • The response to 100 ppm NOx gas reached to 68.9%, and the response time was only 6 s. In this study, a kind of unfamiliar 3D ball-flower morphology ZnO was prepared through a facile and low cost hydrothermal reaction method which was assembled with 50 nm thickness ZnO nanosheets. A kind of ordered mesoporous ZnO material must be used as precursor in hydrothermal reaction which was prepared by soft template method. The surfaces of the ball-flower morphology ZnO were distributed with 5.2 nm wide ordered mesoporous, which led to the bigger specific surface area in the material, it reached to 108.69 m2 g−1. The morphology, structure and gas sensing performance toward NO x of the prepared material were tested, and the optimum synthesis conditions were determined. At room temperature (25 ℃), the ball-flower ZnO nanomaterial showed the excellent gas response to NO x , whose response to 100 ppm NO x gas reached 68.9 %, the response time was only 6 s, and the detection limit was 1 ppm. It broke the tradition that the pure ZnO showed gas response to NO x only in relatively high temperatures. [ABSTRACT FROM AUTHOR]