Mass Ratio Of ZnO Research Articles

The Development of Polydimethysiloxane/ZnO–GO Antifouling Coatings

The development of antifouling coating for sensor is desirable because the biofilm can shorten sensor’s life and cause inaccurate reading. In this study, a facile one-pot reaction was used to synthesized ZnO–graphene oxide (GO) (ZnO–GO) nanocomposites. Different amount of ZnO–GO was incorporated in the polydimethylsiloxane (PDMS) matrix respectively though a simple solution mixing method, in order to create PDMS/ZnO–GO nanocomposite (PZGO). The coating was obtained directly by spin coating of PZGO/tetrahydrofuran suspension. The hydrophobicity, surface roughness (Ra), surface free-energy (SFE) and nanoscale structure were investigated as antifouling factors. Antifouling tests were performed using two marine microorganisms, the cyanobacterium Synechococcus sp. Strain PCC 7002 and the diatom Phaeodactylum tricornutum. PZGO0.2 (mass ratio of ZnO–GO to PDMS: 0.2 wt%) displayed excellent antifouling property with 8.5% of Synechococcus sp. Strain PCC 7002 biofilm coverage, while PZGO0.1 (mass ratio of ZnO–GO to PDMS: 0.1 wt%) showed 2.4% P. tricornutum biofilm coverage. The antifouling property of the synthesized PZGO nanocomposite can be attributed to its high Ra and hydrophobicity which was caused by the good dispersion of ZnO–GO in PDMS matrix. This study suggests a potential of PZGO nanocomposite for sensor’s antifouling coating, which could contribute to improve sensor’s durability relating to biofouling in future.Graphic

A Novel Process for the Preparation of ZnO Nanoparticles and ZnO/Ni0.5Zn0.5Fe₂O₄ Nanocomposites.

A novel solution combustion and gel calcination process for the preparation of ZnO nanoparticles and ZnO/Ni0.5Zn0.5Fe₂O₄ nanocomposites was introduced. The phase identification, morphologies and magnetic properties of ZnO nanoparticles and ZnO/Ni0.5Zn0.5Fe₂O₄ nanocomposites were confirmed by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscope (TEM), vibrating sample magnetometer (VSM). The results showed that the concentration of zinc nitrate and the calcination temperature were two key factors for the grain size, crystallinity and properties of ZnO nanoparticles, while, the mass ratio of ZnO and Ni0.5Zn0.5Fe₂O₄ in ZnO/Ni0.5Zn0.5Fe₂O₄ nanocomposites was the important factor for the specific magnetizations (Ms) of ZnO/Ni0.5Zn0.5Fe₂O₄ nanocomposites.

Photo-degradation of Acid Yellow 11 in aqueous on nano-ZnO/Bentonite under ultraviolet and visible light irradiation

Nano-ZnO particle supported on Bentonite (ZnO/Bentonite) was prepared by the sol–gel method using zinc acetate and lithium hydroxide as raw material and Bentonite as supporter. ZnO/Bentonite was characterized by XRD, UV–vis and TEM. Photo-catalytic performance of ZnO/Bentonite was tested by removal of Acid Yellow 11 under ultraviolet (UV) and visible light (VL) irradiation. The result showed that about 5nm of hexagonal structure ZnO was acquired and uniformly loaded on the Bentonite. When the mass ratio of ZnO and Bentonite was 3:2, removal of Acid Yellow 11 was reached 90% after 280min under UV irradiation. ZnO/Bentonite has a satasfactory photocatalytic activity under UV or VL. The order of photocatalytic efficiency was ZnO/Bentonite-UV>ZnO/Bentonite-VL>ZnO-UV.

Mechanism and Experimental Research on Improvement in Conductive Performances of ZnO Coated Tourmaline Powder

The heterogeneous conglomeration method, chemical precipitation method and Hydroxy combination theory are adopted in the paper through detailed theoretical analysis and contrast experiments. Tourmaline powder surface is completely covered with ZnO by 1.2:1 mass ratio of ZnO to tourmaline powder. Submicron-nanometer powder is achieved due to 78.71 mean particle diameter, the electrical resistivity of composite powder is decreased to 7.45Ω.cm. Improvement of conductive performance extends the application of tourmaline in the field of environmental purification.

MOX (M = Zn, Co, Fe)/AP shell–core nanocomposites for self-catalytical decomposition of ammonium perchlorate

To overcome the agglomeration of metal oxide (MOX) nanocatalysts mechanically mixed with ammonium perchlorate (AP) and other additives of rocket propellant, the shell–core nanocomposites of MOX/AP have been synthesized successfully by a facile liquid deposition method at room temperature. SEM analysis revealed that MOX (M = Zn, Co, Fe) nanoparticles were deposited on the surface of AP particles as either a continuous thin layer or small clusters. Owing to the existence of the shell of MOX nanocatalysts, ZnO/AP, Co 3O 4/AP and Fe 2O 3/AP nanocomposites showed excellent self-catalytic performances for AP thermal decomposition: lowering the decomposition temperature from 398 °C to 272 °C, 285 °C, 337 °C, and increasing the heat release from 584 J g −1 to 1137 J g −1, 1237 J g −1, 1010 J g −1, respectively. Moreover, their self-catalytic performances mainly relied on the content of MOX nanocatalysts, which was controlled by the concentration of metal salts in the precursor solution. In particular, ZnO/AP nanocomposites with the mass ratio of ZnO:AP = 4:100 exhibited the best self-catalytic performance in decreasing the activation energy from 154.0 kJ/mol to 96.5 kJ/mol. The MOX/AP (M = Zn, Co, Fe) shell–core nanocomposites could have a promising application in the rocket propellant for improving the thermal-catalytic decomposition performance of AP.

An aluminum borate whisker-reinforced aluminum matrix composite with high plasticity

A pure aluminum matrix composite reinforced by ZnAl 2O 4-coated Al 18B 4O 33 whiskers was fabricated by a squeeze casting technique. The effect of ZnAl 2O 4 coating content on the wettability between whiskers and matrix, the ultimate tensile strength and elongation to fracture of the composite were investigated. The results show that the interface wettability and the ultimate tensile strength increase with increasing the coating content. The coating content remarkably affects the elongation to fracture of composites. When the mass ratio of ZnO and ABOw is 1:30, the elongation to fracture of the composite can reach 7.9% at room temperature.