Complexional Ultrafine Zinc Oxide Powders Prepared by Controlled-Release Precipitation

2011 ◽  
Vol 306-307 ◽  
pp. 1369-1374
Author(s):  
Zhi Fang Tong ◽  
Yinq Jie Li ◽  
Li Xiu Lian
Keyword(s):  
Zinc Oxide ◽  
Controlled Release ◽  
Average Particle Size ◽  
Ammonia Solution ◽  
Precipitation Method ◽  
Precipitation Process ◽  
Average Particle ◽  
X Ray Diffraction ◽  
Oxide Powders ◽  
Wide Range

The synthesis of complexional ultrafine zinc oxide powders by controlled-release precipitation method, which is a precipitation process of precursor by controlling ammonia distillation rate in ammonia solution under the combination effect of microwave heating and ultrasonic cavitating, and followed by subsequent heat treatment was investigated. The characteristic of precursor and zinc oxide powders were studied using X-ray diffraction, scanning electron microscopy, TG-DTA-DTG, FT-IR, and ultraviolet-visible pectrophotometer. The coloring mechanism of complexional zinc oxide is discussed. This has shown that a tentative composition of the precursor is likely Zn3CO3(OH)4·H2O. Complexional zinc oxide particles of an average particle size of 200 nm with narrow size distribution, good dispersibility and hexagonal appearance could be obtained after annealing at 350°C for 1.5 hour. ZnO particles are complexional, probably due to nitrogen atom or N-H bond entering into crystal lattice of zinc oxide. Complexional zinc oxide has fine capacity of shielding UV and absorbing wide range of wavelength.

Preparation BiTaO4 by Precipitation Method and its Visible-Light Photocatalytic Activity

2012 ◽  
Vol 178-181 ◽  
pp. 535-538
Author(s):  
Jing Jiao Zhang ◽  
Pei Song Tang
Keyword(s):  
Photocatalytic Activity ◽  
Visible Light ◽  
Diffuse Reflectance Spectroscopy ◽  
Raw Materials ◽  
Average Particle Size ◽  
Precipitation Method ◽  
Precipitation Process ◽  
Average Particle ◽  
X Ray Diffraction ◽  
Uv Visible

The single phase BiTaO4was synthesized using Ta2O5and Bi(NO3)3as main raw materials by precipitation process. The products were characterized by thermogravimetry and differential thermal analysis (TG-DTA), powder X-ray diffraction (XRD), scanning electron microscopy (SEM) and UV-visible diffuse reflectance spectroscopy (DRS). The results show that BiTaO4was triclinic crystal with average particle size 100nm, and a band gap of about 2.77 eV. The photocatalytic experiment of BiTaO4shows the good photocatalytic activity for the decomposition of methylene blue under visible-light irradiation.

scholarly journals Hydrothermal synthesis of tetragonal barium titanate nanopowders under moderate conditions

2021 ◽  
Vol 15 (2) ◽  
pp. 179-183
Author(s):  
Huaxing Meng ◽  
Zhiwu Chen ◽  
Zhenya Lu ◽  
Xin Wang ◽  
Xiaoyi Fu
Keyword(s):  
Barium Titanate ◽  
Average Particle Size ◽  
Ammonia Solution ◽  
Average Particle ◽  
Titanium Hydroxide ◽  
X Ray Diffraction ◽  
Hydrothermal Route ◽  
Uniform Size ◽  
Dominant Structure ◽  
Hydrolysis Of

Monodispersed tetragonal barium titanate (BaTiO3) nanopowders were synthesized by a convenient hydrothermal route at a low temperature of 200?C in only 24 h. The key point of this method is to promote the generation of ultrafine titanium hydroxide precipitation precursors with the help of absolute ethyl alcohol and ammonia solution during the hydrolysis of Ti(OC4H9)4. The results of X-ray diffraction and Raman spectra show that the as-prepared BaTiO3 nanopowders possess tetragonal-dominant structure. The synthesized tetragonal BaTiO3 nanopowders exhibit relatively uniform size and good dispersity, with the average particle size of 96.1 nm and a tetragonality of 1.0073, which enable broad application prospects in the field of multilayer ceramic capacitors.

Preparation and Antibacterial Performances of Electrocatalytic Zinc Oxide Nanoparticles with Diverse Morphologies

2021 ◽  
Vol 17 (9) ◽  
pp. 1824-1829
Author(s):  
Junlin Li ◽  
Xiangfei Li ◽  
Dong Liang ◽  
Xiaojuan Zhang ◽  
Qing Lin ◽  
...  
Keyword(s):  
Zinc Oxide ◽  
Surface Area ◽  
Zinc Oxide Nanoparticles ◽  
Average Particle Size ◽  
Three Dimensional ◽  
Diffusion Method ◽  
Oxide Nanoparticles ◽  
Average Particle ◽  
X Ray Diffraction ◽  
Zno Nps

This study exploits the potential of zinc oxide nanoparticles (ZnO-NPs) with diverse morphologies as catalysts and antibacterial agent. Spherical ZnO-NPs, rod-shaped ZnO-NPs and flower-shaped ZnO-NPs were prepared by microemulsion method, solvent heat method and hydrothermal method, respectively. The structural characterizations of samples were investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. XRD results revealed the formation of spherical ZnO-NPs, rod-shaped ZnO-NPs and flower-shaped ZnO-NPs were all wurtzite crystal structure. SEM results showed that spherical ZnO-NPs had an average particle size of 30–40 nm, rod-shaped ZnO-NPs were about 500 nm long and 100 nm wide with obvious hexagonal crystals. Flower-shaped ZnO-NPs had a three-dimensional appearance with obvious petals. Results of electrochemical HER (Hydrogen evolution reaction) experiments revealed that spherical ZnO-NPs exhibited the highest electrocatalytic activity at the lowest potential voltage due to their largest specific surface area. The antibacterial property of ZnO-NPs samples were studied by the optical density method and disc diffusion method. All samples had antibacterial effects against E. coli. and flower-shaped ZnO-NPs showed the best antibacterial activity due to the largest surface area in comparison with spherical ZnO-NPs and rod-shaped ZnO-NPs, which promised the maximum Zn2+ release as bactericide mechanism that registered in the case of different ZnO-NPs morphologies.

Preparation of Nanosized Barium Titanate Powder by a Direct Reactive Precipitation Method

2013 ◽  
Vol 690-693 ◽  
pp. 454-457
Author(s):  
Hong Bo Li ◽  
Shu Yan Wu ◽  
Jing Wang ◽  
Chun Jie Li
Keyword(s):  
Particle Size ◽  
Reaction Temperature ◽  
Surface Active Agent ◽  
Average Particle Size ◽  
Active Agent ◽  
Precipitation Method ◽  
Precipitation Process ◽  
Average Particle ◽  
Powder Particle Size ◽  
Powder Morphology

Columnar crystaldendriteequiaxial dendritescolumnar crystalNanosized powder was synthesized by direct-reactive precipitation process using a stoichiometrical mixture of TiCl4, BaCl2 as the reactants while NaOH as precipitant. Under the ratio of Ba to Ti is 1.02, PH=13, three reaction temperature of 70°C, 80°C and 90°C were conducted respectively. Morphology and phase structure of powder were investigated, and the influence of reaction temperature on powder morphology was discussed. The result indicates that synthesized powder is single cubic BaTiO3 and contains no impurities. BaTiO3 powders generally show spherical, and average particle size decreases with increasing reaction temperature. When reaction temperature is 80°C, BaTiO3 powder has best uniformity and dispersivity with the diameter of 80-100nm. The influence of reaction temperature on powder particle size can be attributed to the corporate contribution of nucleation and growth rate. Polyglycol as surface active agent has a significant effect in restraining agglomeration.

Effect of Surfactant on the Preparation of Nano-powder for Yb Doping Laser Transparent YAG Ceramic

2013 ◽  
Vol 32 (5) ◽  
pp. 511-515 ◽  
Author(s):  
Xiao Guo Cao ◽  
Jia Wang ◽  
Qi Bai Wu ◽  
Hai Yan Zhang
Keyword(s):  
Particle Size ◽  
Polyethylene Glycol ◽  
Average Particle Size ◽  
Ammonium Bicarbonate ◽  
Spherical Particles ◽  
Precipitation Method ◽  
Average Particle ◽  
X Ray Diffraction ◽  
Nano Powder ◽  
Co Precipitation

AbstractYb:YAG transparent ceramic nano-powder was prepared by chemical co-precipitation method, with ammonium bicarbonate as the precipitant and polyethylene glycol as surfactant. The addition of polyethylene glycol can reduce the agglomeration and particle size of the prepared Yb:YAG powder. The morphology, thermal stability and phase structure of Yb:YAG nano-powder were charactered by scanning electron microscopy (SEM), thermogravimetry and differential thermal analysis (TG-DTA), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy. The results show that well-crystallized nano-powder was obtained by calcining the precursors at 900 °C for 3 h. The average particle size of Yb:YAG powder is about 100–200 nm. When the volume amount of polyethylene glycol is 2.0%, well-dispersed Yb:YAG powder with spherical particles of 100 nm diameter was obtained.

scholarly journals Zinc Oxide Synthesis from Extreme Ratios of Zinc Acetate and Zinc Nitrate: Synergistic Morphology

Materials ◽  
2022 ◽  
Vol 15 (2) ◽  
pp. 570
Author(s):  
Sujittra Kaenphakdee ◽  
Pimpaka Putthithanas ◽  
Supan Yodyingyong ◽  
Jeerapond Leelawattanachai ◽  
Wannapong Triampo ◽  
...  
Keyword(s):  
Zinc Oxide ◽  
Optical Properties ◽  
Zinc Acetate ◽  
Near Infrared ◽  
Synergistic Effects ◽  
Zinc Nitrate ◽  
Precipitation Method ◽  
X Ray Diffraction ◽  
Oxide Powders ◽  
Zno Powders

The synthesis of ZnO comprising different ratios of zinc acetate (ZA) and zinc nitrate (ZN) from the respective zinc precursor solutions was successfully completed via a simple precipitation method. Zinc oxide powders with different mole ratios of ZA/ZN were produced—80/1, 40/1, and 20/1. The crystallinity, microstructure, and optical properties of all produced ZnO powders were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), and UV-Vis-NIR spectrophotometry. The average agglomerated particle sizes of ZnO-80/1, ZnO-40/1, and ZnO-20/1 were measured at 655, 640, and 620 nm, respectively, using dynamic light scattering (DLS). The optical properties of ZnO were significantly affected by the extreme ratio differences in the zinc precursors. ZnO-80/1 was found to have a unique coral-sheet structure morphology, which resulted in its superior ability to reflect near-infrared (NIR) radiation compared to ZnO-40/1 and ZnO-20/1. The NIR-shielding performances of ZnO were assessed using a thermal insulation test, where coating with ZnO-80/1 could lower the inner temperature by 5.2 °C compared with the neat glass substrate. Due to the synergistic effects on morphology, ZnO-80/1 exhibited the property of enhanced NIR shielding in curtailing the internal building temperature, which allows for its utilization as an NIR-reflective pigment coating in the construction of building envelopes.

scholarly journals Study Microstructure of Fe3O4 Modification Using PEG 4000 form Iron Sand at Wari Ino Beach As A Biosensor Application

2021 ◽  
Vol 8 (3) ◽  
pp. 168-171
Author(s):  
Kurnia Kurnia ◽  
Meidy Kaseside ◽  
Steven Iwamony
Keyword(s):  
Average Particle Size ◽  
Precipitation Method ◽  
High Dispersion ◽  
Average Particle ◽  
X Ray Diffraction ◽  
Xrd Pattern ◽  
Peg 4000 ◽  
Biosensor Application ◽  
Scherrer Formula ◽  
Co Precipitation

Fe3O4 encapsulated PEG form iron sand at wari ino beach has been successfully synthesized by co-precipitation method. The average particle size  of the nanoparticle 11,3 nm was determined by scherrer formula. Fe3O4 modification PEG 4000 was successfully encapsulated the samples  by the presence C-O-C and CH bonding that were characterized using Fourier Transform Infra Red (FTIR), X-Ray Diffraction (XRD) pattern  shows that all samples  are formed by single  phase cubic spinel magnetite  , and Scanning Electron Microscopy (SEM) shows the  high dispersion capability while encapsulated process using  PEG. The results of the characterization show that the Fe3O4 successfully encapsulated by PEG 4000.

scholarly journals Synthesis and characterization of ZnTe nanoparticles

2016 ◽  
Vol 17 (1) ◽  
pp. 1-3 ◽  
Author(s):  
Sujan Dhungana ◽  
Bhoj Raj Paudel ◽  
Surendra K. Gautam
Keyword(s):  
Particle Size ◽  
Field Effect Transistors ◽  
Average Particle Size ◽  
Precursor Solution ◽  
Chemical Precipitation ◽  
Precipitation Method ◽  
Average Particle ◽  
X Ray Diffraction ◽  
Zinc Compounds ◽  
Transmission Electron

In this work, we report the ZnTe semiconductor nanoparticles (NPs) prepared by aqueous chemical precipitation method using the tellurium precursor solution with different zinc compounds. Three batches of ZnTe NPs were synthesized to study the effect of dilution on the size and phase purity of ZnTe. The influence of source compounds and concentrations of the size and structure of NPs were studied. ZnTe NPs have great applications as field-effect transistors and photodetectors. The existing controversy regarding the crystalline structure of ZnTe NPs, whether it is cubic or hexagonal, has been resolved using X-ray Diffraction (XRD) data. The ZnTe NPs possess cubic structure, which is also confirmed by Electron Diffraction (ED) pattern. The average particle size determined from XRD data with the help of Debye-Scherrer equation is about 6 nm. The particle size can be further verified by Transmission Electron Microscopy (TEM) studies.  

scholarly journals PCL/PHBV Microparticles as Innovative Carriers for Oral Controlled Release of Manidipine Dihydrochloride

2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
Fernanda Malaquias Barboza ◽  
Willian Moreira Machado ◽  
Luiz Renato Olchanheski Junior ◽  
Josiane Padilha de Paula ◽  
Sônia Faria Zawadzki ◽  
...  
Keyword(s):  
Controlled Release ◽  
Animal Studies ◽  
Average Particle Size ◽  
Spherical Shape ◽  
Average Particle ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Chemically Modified ◽  
Diffraction Patterns

Microparticles of poly(ε-caprolactone) (PCL) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) containing manidipine dihydrochloride (MAN) were successfully prepared by the simple emulsion/solvent evaporation method. All formulations showed loading efficiency rates greater than 80% and average particle size less than 8 μm. Formulations had spherical shape with smooth and porous surface for PCL and PHBV, respectively. According to Fourier-transform infrared spectroscopy, initial components were not chemically modified during microencapsulation. X-ray diffraction patterns and differential scanning calorimetry demonstrated that this process led to drug amorphization.In vitrodissolution studies showed that all microparticles prolonged MAN release, mainly which one obtained using PCL that contained 5% of drug loaded (PCL-M5). Animal studies demonstrated that formulationPCL-M5was able to keep the variation of mean arterial pressure after phenylephrine administration up to 24 hours. These data confirmed the sustained antihypertensive effect of the investigated microparticles. Results provided an experimental basis for using formulationPCL-M5as a feasible carrier for oral controlled release of MAN intended for treating high blood pressure.

Effect of pH on Zinc Oxide Powder Prepared by a Chemical Co-Precipitation Method

2010 ◽  
Vol 93-94 ◽  
pp. 691-694 ◽  
Author(s):  
Pusit Pookmanee ◽  
Issara Attaveerapat ◽  
Jiraporn Kittikul ◽  
Sukon Phanichphant
Keyword(s):  
Zinc Oxide ◽  
Average Particle Size ◽  
Ammonium Hydroxide ◽  
Zinc Nitrate ◽  
Oxide Powder ◽  
Precipitation Method ◽  
Average Particle ◽  
X Ray ◽  
Zinc Oxide Powder ◽  
Co Precipitation

Zinc oxide powder was prepared by a chemical co-precipitation method. Zinc nitrate and ammonium hydroxide were used as the starting precursors. The white precipitated powder was formed after adding ammonium hydroxide until the pH of final solution was 7-9. The powder was filtered and dried at 100 °C for 24h. The phase of zinc oxide powder was studied by X-ray diffractometer (XRD). Hexagonal single phase of zinc oxide was obtained without calcination step. The morphology of zinc oxide powder was investigated by scanning electron microscope (SEM). The particle was irregular in shape and highly agglomerated with an average particle size of 0.1 µm. The chemical composition of zinc oxide powder was determined by energy dispersive X-ray spectrometer (EDXS). The elemental composition of zinc oxide showed the characteristic X-ray energy value as follows: zinc of Lα = 1.012 keV, Kα = 8.630 keV and Kβ = 9.570 keV and oxygen of Kα = 0.525 keV, respectively.

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