Morphology Controlled Flower-Like ZnO Particles Synthesized by Low Cost High Pressure Cooker

2014 ◽  
Vol 608 ◽  
pp. 159-163
Author(s):  
Pat Sooksaen ◽  
Malin Rapp ◽  
Thipwipa Sirinakorn ◽  
Phatthraporn Meepanya ◽  
Pawanan Leangthammarat
Keyword(s):  
High Pressure ◽  
Hydrothermal Method ◽  
Metal Ion ◽  
Low Cost ◽  
Hexagonal Wurtzite Structure ◽  
Nitrate Hexahydrate ◽  
Sem Images ◽  
Hydrothermal Temperature ◽  
Morphological Studies ◽  
Zno Particles

ZnO is a good candidate material for many optical and optoelectronic applications. ZnO with various shapes and sizes can be prepared via chemical methods such as precipitation, microwave heating and hydrothermal method. Generally ZnO synthesized by hydrothermal method uses autoclave which is expensive and gives low % yield. This research applied a low cost high pressure cooker which replaced the use autoclave to synthesize ZnO as its concept is similar to hydrothermal method. In this study, it was found that the size and shape of the synthesized ZnO particles were affected by several factors such as Zn2+/OH- ratio, temperature and time. Zinc nitrate hexahydrate, Zn(NO3)2.6H2O and sodium hydroxide, NaOH were used as metal ion sources in the precursor solutions. Structural and morphological studies were performed by X-ray diffraction (XRD) and scanning electron microscope (SEM). The effect of Zn2+/OH- ion ratios, hydrothermal temperature and time on the size and morphology of ZnO were discussed in detail. All the synthesized conditions yielded hexagonal wurtzite structure of ZnO confirmed by XRD, without calcinations process. SEM images showed plate-like structure for Zn2+/OH- ratio = 1:7.5 and 1:15 and flower structure for Zn2+/OH- ratio = 1:20. Sizes of the synthesized ZnO particles decreased with increasing hydrothermal temperature from 120to 200°C. The longer the synthesized time period the larger the ZnO particles obtained.

Synthesis and Photoluminescence of Cr-Doped Rod-Like ZnO Particles by Hydrothermal Method

2011 ◽  
Vol 306-307 ◽  
pp. 176-179 ◽  
Author(s):  
Lian Mao Hang ◽  
Zhi Yong Zhang ◽  
Jun Feng Yan
Keyword(s):  
Hydrothermal Method ◽  
Room Temperature ◽  
Blue Emission ◽  
Hexagonal Wurtzite Structure ◽  
Secondary Phases ◽  
X Ray Diffraction ◽  
Structural And Optical Properties ◽  
X Ray ◽  
Zno Particles ◽  
Strong Blue Emission

Cr-doped rod-like ZnO particles with nominal 3 at% doping concentration were synthesized by hydrothermal method. The structural and optical properties of the sample were investigated by X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM) and photoluminescence (PL). The results show that the as-synthesized product is of hexagonal wurtzite structure without metallic Cr or other secondary phases and the morphology of the ZnO particles is rod shaped. The room-temperature PL spectrum of the Cr-doped rod-like ZnO particles exhibits a strong blue emission at 440nm and two weak emission bands centered at 410nm and 565nm, respectively.

scholarly journals Comparative Study on the Adsorption Kinetics and Thermodynamics of Metal Ions onto Acid Activated Low Cost Pandanus Carbon

2007 ◽  
Vol 4 (2) ◽  
pp. 238-254 ◽  
Author(s):  
R. Sudha ◽  
K. Kalpana ◽  
T. Rajachandrasekar ◽  
S. Arivoli
Keyword(s):  
Metal Ions ◽  
Metal Ion ◽  
Low Cost ◽  
Freundlich Isotherm ◽  
Kinetic Studies ◽  
Ion Concentration ◽  
Effect Of Temperature ◽  
Ferrous Ions ◽  
Sem Images ◽  
Operating Variables

Batch experiments were carried out for the sorption of Copper and Ferrous ions onto acid activated carbon prepared. The operating variables studied were initial metal ion concentration, pH, and temperature and contact time. The equilibrium data were fitted to the Langmuir and Freundlich isotherm equations. From this adsorption efficiency, adsorption energy, adsorption capacity, intensity of adsorption and dimensionless separation factor were calculated. From the kinetic studies the rate constant values for the adsorption process was calculated. From the effect of temperature thermodynamic parameters like ΔG°, ΔH°, and ΔS° were calculated. The mechanism of adsorption for metal ions onto carbon was investigated by using the experimental results and confirmed by FT- IR, XRD and SEM images.

Hydrothermal Method Preparation of Flower-Like Ce-Doped ZnO as an Efficient Photocatalyst

2018 ◽  
Vol 281 ◽  
pp. 872-877
Author(s):  
Jian Ping Ai ◽  
Wei Xiu Liao ◽  
Shan Shan Luo ◽  
Tao Zhou ◽  
Li Hong Cheng ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Hydrothermal Method ◽  
Uv Light ◽  
Low Cost ◽  
Hexagonal Wurtzite Structure ◽  
X Ray Diffraction ◽  
X Ray ◽  
Infrared Spectrometer ◽  
Ft Ir ◽  
Doped Zno

Well-crystalline flower-like Ce-doped ZnO were synthesized by facile and low-cost hydrothermal method. The prepared samples were characterized by a variety of characterization techniques such as X-ray diffraction (XRD), Fourier Transform Infrared Spectrometer (FT-IR), UV-visible spectroscopy, scanning electron microscopy (SEM) combined with energy dispersive X-ray diffraction (EDX), to study the crystal structure, optical properties, surface morphology and chemical composition. It was observed from XRD and FT-IR results that synthesized powder had hexagonal wurtzite structure. The photocatalytic activities of the prepared samples were evaluated by photocatalytic degradation of methyl orange (MO) and Rhodamine B (RhB) under UV light irradiation. The results showed that the Ce-doped ZnO photocatalyst with 0.5% cerium exhibited highest photocatalytic activity compared to other samples. The enhanced photocatalytic activity could be attributed to inhibition of the electron-hole pair’s recombination.

Chromic Acid Etching of Polyethylene

1973 ◽  
Vol 31 ◽  
pp. 72-73
Author(s):  
J. D. Muzzy ◽  
R. D. Hester ◽  
J. L. Hubbard
Keyword(s):  
Chromic Acid ◽  
Low Cost ◽  
Acid Etching ◽  
Crystalline Morphology ◽  
Bulk Specimen ◽  
Morphological Studies ◽  
Perfect Form ◽  
Molecular Length ◽  
Lamellar Texture ◽  
Cost Studies

Polyethylene is one of the most important plastics produced today because of its good physical properties, ease of fabrication and low cost. Studies to improve the properties of polyethylene are leading to an understanding of its crystalline morphology. Polyethylene crystallized by evaporation from dilute solutions consists of thin crystals called lamellae. The polyethylene molecules are parallel to the thickness of the lamellae and are folded since the thickness of the lamellae is much less than the molecular length. This lamellar texture persists in less perfect form in polyethylene crystallized from the melt.Morphological studies of melt crystallized polyethylene have been limited due to the difficulty of isolating the microstructure from the bulk specimen without destroying or deforming it.

scholarly journals Multidimensional Ln-Aminophthalate Photoluminescent Coordination Polymers

Materials ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1786
Author(s):  
Carla Queirós ◽  
Chen Sun ◽  
Ana M. G. Silva ◽  
Baltazar de Castro ◽  
Juan Cabanillas-Gonzalez ◽  
...  
Keyword(s):  
Water Content ◽  
Coordination Polymers ◽  
Metal Ion ◽  
Low Cost ◽  
Microwave Assisted Synthesis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Wide Range ◽  
Ft Ir ◽  
Ft Ir Spectroscopy

The development of straightforward reproducible methods for the preparation of new photoluminescent coordination polymers (CPs) is an important goal in luminescence and chemical sensing fields. Isophthalic acid derivatives have been reported for a wide range of applications, and in addition to their relatively low cost, have encouraged its use in the preparation of novel lanthanide-based coordination polymers (LnCPs). Considering that the photoluminescent properties of these CPs are highly dependent on the existence of water molecules in the crystal structure, our research efforts are now focused on the preparation of CP with the lowest water content possible, while considering a green chemistry approach. One- and two-dimensional (1D and 2D) LnCPs were prepared from 5-aminoisophthalic acid and Sm3+/Tb3+ using hydrothermal and/or microwave-assisted synthesis. The unprecedented LnCPs were characterized by single-crystal X-ray diffraction (SCRXD), powder X-ray diffraction (PXRD), Fourier transform infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM), and their photoluminescence (PL) properties were studied in the solid state, at room temperature, using the CPs as powders and encapsulated in poly(methyl methacrylate (PMMA) films, envisaging the potential preparation of devices for sensing. The materials revealed interesting PL properties that depend on the dimensionality, metal ion, co-ligand used and water content.

scholarly journals Equilibrium and Kinetic Study of Anionic and Cationic Pollutants Remediation by Limestone–Chitosan–Alginate Nanocomposite from Aqueous Solution

Molecules ◽  
2021 ◽  
Vol 26 (9) ◽  
pp. 2586
Author(s):  
Inas A. Ahmed ◽  
Ahmed H. Ragab ◽  
Mohamed A. Habila ◽  
Taghrid S. Alomar ◽  
Enas H. Aljuhani
Keyword(s):  
Physical Adsorption ◽  
Low Cost ◽  
Freundlich Isotherm ◽  
Entropy Change ◽  
Sem Images ◽  
Bet Analysis ◽  
Adsorption Processes ◽  
Equilibrium Data ◽  
Pseudo Second Order ◽  
Multilayer Formation

In this work, low-cost and readily available limestone was converted into nanolimestone chitosan and mixed with alginate powder and precipitate to form a triple nanocomposite, namely limestone—chitosan–alginate (NLS/Cs/Alg.), which was used as an adsorbent for the removal of brilliant green (BG) and Congo red (CR) dyes in aqueous solutions. The adsorption studies were conducted under varying parameters, including contact time, temperature, concentration, and pH. The NLS/Cs/Alg. was characterized by SEM, FTIR, BET, and TEM techniques. The SEM images revealed that the NLS/Cs/Alg. surface structure had interconnected pores, which could easily trap the pollutants. The BET analysis established the surface area to be 20.45 m2/g. The recorded maximum experimental adsorption capacities were 2250 and 2020 mg/g for CR and BG, respectively. The adsorption processes had a good fit to the kinetic pseudo second order, which suggests that the removal mechanism was controlled by physical adsorption. The CR and BG equilibrium data had a good fit for the Freundlich isotherm, suggesting that adsorption processes occurred on the heterogeneous surface with a multilayer formation on the NLS/Cs/Alg. at equilibrium. The enthalpy change (ΔH0) was 37.7 KJ mol−1 for CR and 8.71 KJ mol−1 for BG, while the entropy change (ΔS0) was 89.1 J K−1 mol−1 for CR and 79.1 J K−1 mol−1 BG, indicating that the adsorption process was endothermic and spontaneous in nature.

scholarly journals New Brightener for Zn-Fe Alloy Plating from Sulphate Bath

2011 ◽  
Vol 2011 ◽  
pp. 1-8 ◽  
Author(s):  
B. M. Praveen ◽  
T. V. Venkatesha
Keyword(s):  
Grain Size ◽  
Metal Ion ◽  
Condensation Product ◽  
Spectroscopic Studies ◽  
Sem Images ◽  
Alloy Electrodeposition ◽  
Fine Grained ◽  
Polarization Studies ◽  
Uv Visible ◽  
Sulphate Bath

Zn-Fe alloy electrodeposition was carried out in the presence of condensation product 2-{[(1E)-(3,4-dimethoxyphenyl)methylidene]amino}-3-hydroxypropanoic acid formed between veratraldehyde and serine in acid sulphate bath. Hull cell was used for optimizing the operating parameters and bath constituents. During deposition, the potential was shifted towards cathodic direction in the presence of addition agents and brightener. The polarization studies show that deposition taking place in basic bath and optimum bath was 1.08 and 1.15 V, respectively. Current efficiency and throwing power were reached around 85% and 26%, respectively. The SEM images of bright deposit indicated its fine-grained nature and appreciable reduction in the grain size. XRD studies have showed that the grain size of the deposit generated from optimum bath was 16 nm. UV-visible spectroscopic studies confirm the formation of complex between metal ion and brightener.

Synthesis of Nano Structured Membrane from Carbon Nanotube for Waste Water Treatment

2013 ◽  
Vol 829 ◽  
pp. 386-390 ◽  
Author(s):  
Mehri Imani ◽  
Alimorad Rashidi ◽  
Mojtaba Shariaty-Niassar ◽  
Elahe Sarlak ◽  
Amir Zarghan
Keyword(s):  
Waste Water ◽  
Carbon Nanotube ◽  
Metal Ion ◽  
Low Cost ◽  
Waste Water Treatment ◽  
Chemical Vapor ◽  
Morphological Properties ◽  
Carbon Membranes ◽  
Vertically Aligned ◽  
Simple Technology

Carbon membranes have high adsorption capacitiy with respect to its incredible properties such as unique structural, electronic, optoelectronic, semiconductor, mechanical, chemical and physical. Carbon nanotube (CNT) membranes because of its high permeance have been recently developed.Great attention has been currently paid to the field of fabrication methods capable of producing uniform, well-aligned and monodispersed CNT array. Current research concerns with fabrication of vertically aligned CNT membrane in order to remove heavy metal ion presents in waste water. For this purpose, CNTs are vertically grown up through the holes of anodic aluminium oxide (AAO); as a template, by chemical vapor deposition (CVD) of acetylene gas.In this work a few heavy metals such as Pb (II), Cu (II) and Cd (II) has been examined for checking the perfomance of membrane in aqueous solution. The morphological properties of the aligned CNT membrane were investigated with scanning electron microscopy (SEM). The method has simple technology, low cost, and easy reproduction.

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