Synthesis and Characterisation of Novel Chitosan-Hydroxyapatites Composites Doped with Zinc

2017 ◽  
Vol 264 ◽  
pp. 74-78
Author(s):  
Ismaila Abdullahi ◽  
I. Zainol
Keyword(s):  
Composite Material ◽  
Crystallite Size ◽  
Lattice Constant ◽  
Bone Mineral ◽  
Morphological Features ◽  
Precipitation Method ◽  
The Novel ◽  
Novel Material ◽  
Co Precipitation

The synthesis of a novelzinc doped chitosan-hydroxyapatite (chitosan-HAp) composite was done viain situ co-precipitation method. FTIR results showed that zinc is incorporated into the composite formed and is less crystalline compared to the pure hydroxyapatite (HAp). XRD results obtained showed that the incorporation of zinc into the lattice of the chitosan-HAp led to changes in the crystallinity, crystallite size and lattice constant of the composite material. FESEM images of the samples revealed that the novel material has a morphological features that resemble that of bone mineral.

Synthesis, Characterization and Bioactivity of Chitosan Hydroxyapatite Composite Doped with Strontium

2021 ◽  
Vol 317 ◽  
pp. 217-226
Author(s):  
Ismaila Abdullahi ◽  
Ismail Zainol
Keyword(s):  
Physicochemical Properties ◽  
Calcium Release ◽  
Precipitation Method ◽  
The Novel ◽  
X Ray Diffraction ◽  
X Ray ◽  
Hydroxyapatite Composite ◽  
Novel Material ◽  
Co Precipitation

Chitosan-hydroxyapatite composite doped with strontium was synthesised via in situ co-precipitation method. Physicochemical properties of the composite obtained were analysed using X-ray diffraction (XRD), infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDX) and Thermogravimetry with differential thermal analysis (DT-TGA). The synthesized composite was subjected to bioactivity studies in simulated body fluid (SBF). The calcium release from the sample in SBF was measured using atomic absorption spectroscopy (AAS). The physicochemical properties and bioactivity of the novel composite was compared with that of hydroxyapatite, strontium doped hydroxyapatite and chitosan hydroxyapatite. The in vitro bioactivity studies of the novel composite showed that it has a higher release of Ca2+ in the SBF compared to the other samples. The novel material was also found to induce more Ca2+ deposition after 28 days of immersion in the SBF. Hence, the novel composite material has the potential to be used as biomaterials for clinical application.

scholarly journals Phase Transition and Coefficients of Thermal Expansion in Al2−xInxW3O12 (0.2 ≤ x ≤ 1)

Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 4021
Author(s):  
Andrés Esteban Cerón Cerón Cortés ◽  
Anja Dosen ◽  
Victoria L. Blair ◽  
Michel B. Johnson ◽  
Mary Anne White ◽  
...  
Keyword(s):  
Phase Transition ◽  
Thermal Expansion ◽  
Thermal Shock ◽  
Monoclinic Phase ◽  
Ceramic Materials ◽  
Precipitation Method ◽  
Scanning Calorimetry ◽  
Orthorhombic Crystal ◽  
Co Precipitation

Materials from theA2M3O12 family are known for their extensive chemical versatility while preserving the polyhedral-corner-shared orthorhombic crystal system, as well as for their consequent unusual thermal expansion, varying from negative and near-zero to slightly positive. The rarest are near-zero thermal expansion materials, which are of paramount importance in thermal shock resistance applications. Ceramic materials with chemistry Al2−xInxW3O12 (x = 0.2–1.0) were synthesized using a modified reverse-strike co-precipitation method and prepared into solid specimens using traditional ceramic sintering. The resulting materials were characterized by X-ray powder diffraction (ambient and in situ high temperatures), differential scanning calorimetry and dilatometry to delineate thermal expansion, phase transitions and crystal structures. It was found that the x = 0.2 composition had the lowest thermal expansion, 1.88 × 10−6 K−1, which was still higher than the end member Al2W3O12 for the chemical series. Furthermore, the AlInW3O12 was monoclinic phase at room temperature and transformed to the orthorhombic form at ca. 200 °C, in contrast with previous reports. Interestingly, the x = 0.2, x = 0.4 and x = 0.7 materials did not exhibit the expected orthorhombic-to-monoclinic phase transition as observed for the other compositions, and hence did not follow the expected Vegard-like relationship associated with the electronegativity rule. Overall, compositions within the Al2−xInxW3O12 family should not be considered candidates for high thermal shock applications that would require near-zero thermal expansion properties.

An elegant synthesis of chitosan grafted hydrotalcite nano-bio composite material and its effective catalysis for solvent-free synthesis of jasminaldehyde

RSC Advances ◽  
2015 ◽  
Vol 5 (115) ◽  
pp. 94562-94570 ◽  
Author(s):  
Jacky H. Adwani ◽  
Noor-ul H. Khan ◽  
Ram S. Shukla
Keyword(s):  
Composite Material ◽  
Layered Double Hydroxide ◽  
Solvent Free ◽  
Precipitation Method ◽  
Co Precipitation ◽  
Double Hydroxide ◽  
Solvent Free Synthesis

A novel nano-bio composite of chitosan and a layered double hydroxide elegantly synthesized by a co-precipitation method had effectively and selectively catalysed the jasminaldehyde synthesis.

scholarly journals Crystallographic, Energy Gap, Photoluminescence and Photo-Catalytic Investigation of Cu Doped Cd0.9Zn0.1S Nanostructures by Co-Precipitation Method

2021 ◽  
Author(s):  
P. Raju ◽  
Joseph Prince Jesuraj ◽  
S. Muthukumaran
Keyword(s):  
Crystallite Size ◽  
Energy Gap ◽  
Wavelength Region ◽  
Lattice Parameter ◽  
Precipitation Method ◽  
Optical Absorbance ◽  
Stability Measurement ◽  
Cubic Structure ◽  
The Stability ◽  
Co Precipitation

Abstract The controlled synthesis of Cd0.9Zn0.1S, Cd0.89Zn0.1Cu0.01S and Cd0.87Zn0.1Cu0.03S nanostructures by simple chemical co-precipitation technique was reported. The XRD investigation confirmed the basic CdS cubic structure on Zn-doped CdS and also Zn, Cu dual doped CdS with no secondary/impurity related phases. No modification in cubic structure was detected during the addition of Zn/Cu into CdS. The reduction of crystallite size from 63 Å to 40 Å and the changes in lattice parameter confirmed the incorporation of Cu into Cd0.9Zn0.1S and generation of Cu related defects. The shift of absorption edge along upper wavelength region and elevated absorption intensity by Cu doping can be accredited to the collective consequence of quantization and the generation of defect associated states. The enhanced optical absorbance and the reduced energy gap recommended that Cd0.87Zn0.1Cu0.03S nanostructure is useful to enhance the efficiency of opto-electronic devices. The presence of Cd-S / Zn-Cd-S /Zn/Cu-Cd-S chemical bonding were confirmed by Fourier transform infrared investigation. The elevated green emissions by Cu incorporation was explained by decrease of crystallite size and creation of more defects. Zn, Cu dual doped CdS nanostructures are recognized as the possible and also efficient photo-catalyst for the removal dyes like methylene blue. The enhanced photo-catalytic behaviour of Zn, Cu dual doped CdS is the collective consequences of high density electron-hole pairs creation, enhanced absorbance in the visible wavelength, surface area enhancement, reduced energy gap and the formation of novel defect associated states. The stability measurement signified that Cu doped Cd0.9Zn0.1S exhibits superior dye removal ability and better stability even after 6 repetitive runs with limited photo-corrosion.

Biocompatible microcrystalline cellulose particles from cotton wool and magnetization via a simple in situ co-precipitation method

2017 ◽  
Vol 170 ◽  
pp. 72-79 ◽  
Author(s):  
Mehnaz Rashid ◽  
Mohammad Abdul Gafur ◽  
Mostafa Kaiyum Sharafat ◽  
Hideto Minami ◽  
Mohd Abdul Jalil Miah ◽  
...  
Keyword(s):  
Microcrystalline Cellulose ◽  
Precipitation Method ◽  
Cotton Wool ◽  
Co Precipitation

scholarly journals Ionic Liquids as Delaminating Agents of Layered Double Hydroxide during In-Situ Synthesis of Poly (Butylene Adipate-co-Terephthalate) Nanocomposites

Nanomaterials ◽  
2019 ◽  
Vol 9 (4) ◽  
pp. 618 ◽  
Author(s):  
Hynek Beneš ◽  
Jana Kredatusová ◽  
Jakub Peter ◽  
Sébastien Livi ◽  
Sonia Bujok ◽  
...  
Keyword(s):  
Food Packaging ◽  
Water Vapor Permeability ◽  
Nanocomposite Films ◽  
Precipitation Method ◽  
Vapor Permeability ◽  
Inorganic Particles ◽  
In Situ Preparation ◽  
End Use ◽  
Co Precipitation

Currently, highly demanded biodegradable or bio-sourced plastics exhibit inherent drawbacks due to their limited processability and end-use properties (barrier, mechanical, etc.). To overcome all of these shortcomings, the incorporation of lamellar inorganic particles, such as layered double hydroxides (LDH) seems to be appropriate. However, LDH delamination and homogenous dispersion in a polymer matrix without use of harmful solvents, remains a challenging issue, which explains why LDH-based polymer nanocomposites have not been scaled-up yet. In this work, LDH with intercalated ionic liquid (IL) anions were synthesized by a direct co-precipitation method in the presence of phosphonium IL and subsequently used as functional nanofillers for in-situ preparation of poly (butylene adipate-co-terephthalate) (PBAT) nanocomposites. The intercalated IL-anions promoted LDH swelling in monomers and LDH delamination during the course of in-situ polycondensation, which led to the production of PBAT/LDH nanocomposites with intercalated and exfoliated morphology containing well-dispersed LDH nanoplatelets. The prepared nanocomposite films showed improved water vapor permeability and mechanical properties and slightly increased crystallization degree and therefore can be considered excellent candidates for food packaging applications.

High Catalytic Activity and Stability of Hexaaluminate Catalysts for N2O Decomposition

2013 ◽  
Vol 320 ◽  
pp. 665-669
Author(s):  
Chao Zhang ◽  
Yong Ji Song ◽  
Feng Hua Shi ◽  
Cui Qing Li ◽  
Hong Wang
Keyword(s):  
Catalytic Activity ◽  
Decomposition Reaction ◽  
Precipitation Method ◽  
High Catalytic Activity ◽  
Structure And Properties ◽  
Active Components ◽  
Co Precipitation ◽  
Hexaaluminate Catalysts

In this paper, hexaaluminate oxides LaMAl12O19-σwere prepared by using M=Cu ,Ce and Zn as active components to substitute Al in the hexaaluminate lattice by co-precipitation method. The structure and properties of LaMAl11O19-σcatalyst was characterized with XRD and BET. The results showed LaCuAl11O19-σexhibited significant high catalytic activity for the decomposition reaction of N2O. Under the simulated in situ condition, LaCuAl11O19-σalso indicated significant catalytic activity and stability, with N2O conversion of 90% at 635°C.

STRUCTURAL, SURFACE MORPHOLOGICAL AND MAGNETIC STUDIES OF Zn1−xFexS (x=0.00–0.10) DILUTED MAGNETIC SEMICONDUCTORS GROWN BY CO-PRECIPITATION METHOD

2018 ◽  
Vol 25 (01) ◽  
pp. 1850044
Author(s):  
M. HASSAN ◽  
M. GHAZANFAR ◽  
N. AROOJ ◽  
S. RIAZ ◽  
S. SAJJAD HUSSAIN ◽  
...  
Keyword(s):  
Crystallite Size ◽  
Diluted Magnetic Semiconductors ◽  
Magnetic Semiconductors ◽  
Hysteresis Loops ◽  
Secondary Phase ◽  
Precipitation Method ◽  
Ferromagnetic Behavior ◽  
Magnetic Studies ◽  
Diluted Magnetic ◽  
Co Precipitation

We have fabricated Zn[Formula: see text]FexS ([Formula: see text], 0.02, 0.04, 0.06, 0.08 and 0.10) diluted magnetic semiconductors using co-precipitation method. X-ray diffraction patterns depict that Zn[Formula: see text]FexS appears as a dominant phase with cubic zinc blende structure and nanoscale crystallite size. In addition, a secondary phase of rhombohedral ZnS also appears; however, no additional phase arises that primarily belongs to Fe dopant. Using Debye–Scherrer relation, the crystallite size is found to be in the range of 20–27[Formula: see text]nm, which is in good agreement with the crystallite size calculated using the Williamson–Hall (WH) plot method. The appearance of secondary phase provoked to study the residual strain using Stokes–Wilson equation, which is nearly consistent to that observed using WH plot method. The surface morphology, revealed using scanning electron microscopy, depicts non-uniform surface structure with a variety of grains and void dimensions. Hysteresis loops measured for Zn[Formula: see text]FexS at room temperature (RT) illustrate a paramagnetic behavior at higher fields; however, small ferromagnetic behavior is evident due to the small openings of the measured hysteresis loops around the origin. The measured RT ferromagnetism reveals the potential spintronic device applications of the studied diluted magnetic semiconductors.

Synthesis and Characterization of LiFePO4-C/ PANI Composite for Cathode Material of Lithium Ion Battery

2012 ◽  
Vol 585 ◽  
pp. 240-244 ◽  
Author(s):  
Rajeev Sehrawat ◽  
Anjan Sil
Keyword(s):  
Composite Material ◽  
In Situ Polymerization ◽  
Active Material ◽  
Lithium Ion ◽  
Chain Structure ◽  
Raw Material ◽  
Precipitation Method ◽  
Gravimetric Analysis ◽  
Oxidizing Agents

In-situ polymer coated LiFePO4-C composite material has been synthesized using different oxidizing agents viz. (NH4)2S2O8, KMnO4 and K2Cr2O7. Polyaniline (PANI) with chains having diameter ≤ 200 nm have been grown separately by self oxidation process of aniline monomers using the above oxidizing agents. For the synthesis of LiFePO4-C active material, initially raw material FePO4/PANI has been synthesized by chemical precipitation method and added with LiCOOCH3 followed by heat treatment at 700°C under reducing (Ar/H2=90/10) atmosphere for 16 hrs. The synthesized LiFePO4-C material has particle size of about 100 nm. The polymer coated LiFePO4-C composite was synthesized by undergoing in-situ polymerization of aniline monomers added with fixed quantity of LiFePO4-C. XRD analysis reveals formation of single phase pure active material LiFePO4-C and mixed phase containing LiFePO4 to FePO4 for polymer coated LiFePO4-C composite. The carbon content in the LiFePO4-C was estimated to be 5 wt%, however, the PANI content in the composites was different with different oxidizing agent. These PANI contents in the composites synthesized with (NH4)2S2O8, KMnO4 and K2Cr2O7 are 14, 15 and 17 wt% respectively which have been estimated by thermal gravimetric analysis (TGA) of the materials. Electrical conductivities of the composite materials were determined by Impedance spectroscopy method. The composite material synthesized with (NH4)2S2O8 has higher conductivity compared to those synthesized with KMnO4 and K2Cr2O7. The higher conductivity of the composite synthesized with (NH4)2S2O8 may be attributed to the presence of partial chain structure in polymer coating as seen by microstructural observations on the composite.

scholarly journals Study of co-precipitated nanomaterials magnetic MnxCo1-xFe2O4 (with x = 0.50 & 0.75) for Photocatalyst Application in MB degradation

2020 ◽  
Vol 4 (1) ◽  
pp. 36
Author(s):  
Wahid Sidik Sarifuddin ◽  
Utari Utari ◽  
Budi Purnama
Keyword(s):  
Magnetic Properties ◽  
Photocatalytic Activity ◽  
Crystallite Size ◽  
Life Time ◽  
Precipitation Method ◽  
Material Base ◽  
Lattice Constants ◽  
Ferrite Material ◽  
Ray Density ◽  
Co Precipitation

The crystalline structure and magnetic properties of Mn<sub>1-x</sub>Co<sub>x</sub>Fe<sub>2</sub>O<sub>4</sub> (x = 0 &amp; 0.25) was studied in this report. The ferrite materials were synthesized by the chemical co-precipitation method and calcinated at 1000<sup>o</sup>C for 5 hours. The obtained materials were characterized by FTIR, XRD and VSM, and for photocatalytic activity was measured by UV-Vis spectrometer. Vibration bands at tetrahedral and octahedral site were corresponded by <strong> </strong>= 581.56 cm<sup>-1</sup> and  = 465.83 cm<sup>-1</sup> and 474.51 cm<sup>-1</sup> . The obtained ferrite were confirmed by XRD as spinel structure and shown that the addition of number of Mn decreased crystallite size <em>(D)</em> and x-ray density (<em>ρ<sub>x</sub></em>), but lattice constants <em>(a)</em> increased. The crystallite size of samples with x = 0.50 was 34.85 nm, and x = 0.75 was 32.17 nm. The magnetic properties of nanoparticles shown that magnetization saturation <em>(</em><em>Ms)</em>from 42.05 emu/g to 54.16 emu/g increased with the addition of number of Mn. The coercive field (<em>H</em><sub>c</sub>)decreased from 408.27 Oe to 258.37 Oe. Photocatalytic activity was observed by UV-Vis spectrometer, where percentage of MB degradation <em>(E)</em> increase with the addition of number on Mn from 49.08% to 69.06%, either rate constant <em>(k<sub>app</sub>)</em> and half life time<em> (t<sub>1/2</sub>)</em>.  Furthermore, ferrite material base Mn-Co-ferrite has good characteristic to applied for photocatalyst.

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