scholarly journals Chromium (III) Oxide Nanostructures Synthesized from Vernonia Amygdalina Leaves Extract

2020 ◽  
Vol 10 (1) ◽  
pp. 1856-1861
Keyword(s):  
Fourier Transform ◽  
Average Crystallite Size ◽  
Fourier Transform Infrared ◽  
Morphological Properties ◽  
X Ray Diffraction ◽  
Vernonia Amygdalina ◽  
Sem Images ◽  
X Ray ◽  
Chloride Hexahydrate ◽  
Diffraction Patterns

This contribution reports first time synthesis of Cr2O3 nanostructures from chromium (III) chloride hexahydrate precursor using Vernonia amygdalina leaves extract as a reducing and stabilizing agent. Powder X-ray diffraction, Fourier-transform infrared spectroscopy, and scanning electron microscopy techniques were used to study the structural and morphological properties of the as-synthesized Cr2O3 nanostructures. Powder X-ray diffraction patterns spectral analysis showed that hexagonal Cr2O3 nanostructures with an average crystallite size of 23.4 nm were synthesized with the minor appearance of CrO2. SEM images showed that the synthesized nanomaterials are granules. Fourier-transform infrared spectra represent a sharp absorption band at 552 cm-1, which indicates Cr-O-Cr vibrational and stretching modes.

scholarly journals Plant Extract Mediated Synthesis of Nickel Oxide Nanoparticles

2020 ◽  
Vol 2 (2) ◽  
pp. 205-209
Keyword(s):  
Fourier Transform ◽  
Nickel Oxide ◽  
Fourier Transform Infrared ◽  
Oxide Nanoparticles ◽  
X Ray Diffraction ◽  
Leaf Extracts ◽  
Nickel Oxide Nanoparticles ◽  
X Ray ◽  
Chloride Hexahydrate ◽  
Scanning Electron

The present study reports the successful synthesis of nickel oxide nanoparticles using Vernonia amygdalina plant leaf extracts as a chelating agent and nickel (II) chloride hexahydrate (NiCl2•6H2O) as precursor. The synthesized powder was gray black in color and annealed at 500 °C for 2 hours to obtain nickel oxide nanoparticles. Characterization techniques such as powder X-ray diffraction, scanning electron microscopy, and Fourier transform infrared spectroscopy were used to study the structure and morphology of the nanoparticles. Powder X-ray diffraction patterns revealed that nickel oxide nanoparticles with an average crystallite size of 17.86nm were synthesized. Scanning electron microscope images show that the nanoparticles have octahedral structure. Fourier transform infrared spectrophotometer analysis revealed that the strongest bond at 1094.8cm-1 corresponds to stretching vibration mode of Ni-O nanoparticles.

Preparation and Characterization of HAp/TiO2 Nanocomposite for Photocatalytic Degradation of Methyl Orange under UV-Irradiation

2013 ◽  
Vol 829 ◽  
pp. 594-599 ◽  
Author(s):  
Saham Sharifat ◽  
Hossein Zolgharnein ◽  
Abdolghader Hamidifalahi ◽  
Mahnaz Enayati-Jazi ◽  
Entesar Hamid
Keyword(s):  
Fourier Transform ◽  
Photocatalytic Activity ◽  
Methyl Orange ◽  
Uv Irradiation ◽  
Methyl Orange Solution ◽  
Fourier Transform Infrared ◽  
X Ray Diffraction ◽  
Sem Images ◽  
X Ray ◽  
Electron Microscopes

A new in-situ precipitation technique is introduced in this study to prepare hydroxyapatite/titania nanocomposites. This technique provides a better control over the microstructures and phase compositions of nanocomposites. The structure and surface morphology of hydroxyapatite/titania nanocomposite were characterized by X-ray diffraction analysis, Fourier transform infrared spectroscopy and scanning electron microscopes. The photocatalytic activity of hydroxyapatite/titania nanocomposite was evaluated by photocatalytic decolorization of methyl orange in aqueous solution as a model pollutant under UV-irradiation. X-ray diffraction and Fourier transform infrared results indicated that hydroxyapatite and anatase (TiO2) were the major crystalline phases. There had been no reaction between hydroxyapatite and titania compounds. Based on the SEM images, the overall morphology of the samples indicates that there exists a distribution of small particles and large agglomerates.The hydroxyapatite/titania nanocomposite exhibited high photocatalytic activity hydroxyapatite/titania nanocomposite under UV-irradiation. After 8 h of irradiation by UV-irradiation, over 80% of methyl orange solution (5 mg L-1) was decolorized with 1 gL-1 of the photocatalyst. Since this process does not require the addition of hydrogen peroxide and uses UV-irradiation in this study are environmentally friendly method to decolorize azo dye.

PENINGKATAN LAJU DISOLUSI ACYCLOVIR DENGAN METODE SISTEM DISPERSI PADAT MENGGUNAKAN POLOXAMER 188

2016 ◽  
Vol 5 (1) ◽  
pp. 6
Author(s):  
Budi Setiawan ◽  
Erizal Zaini ◽  
Salman Umar
Keyword(s):  
Electron Microscopy ◽  
Thermal Analysis ◽  
Scanning Electron Microscopy ◽  
Fourier Transform ◽  
Differential Thermal Analysis ◽  
Fourier Transform Infrared ◽  
X Ray Diffraction ◽  
Poloxamer 188 ◽  
X Ray ◽  
Scanning Electron

Sebuah penelitian tentang sistem dispersi padat dari asiklovir dengan poloxamer 188 telah dilakukan formulasi dengan pencampuran secara fisika dengan rasio 1 : 1, 1 : 3, 1 : 5 dan dispersi padat 1 : 1, 1 : 3, 1 : 5 dan penggilingan 1:1 sebagai pembanding. Dispersi padat dibuat menggunakan metode pencairan (fusi), yang digabung dengan poloxamer 188 pada hotplate kemudian asiklovir dimasukkan ke dalam hasil poloxamer 188 lalu di kocok hingga membentuk masa homogen. Semua formula yang terbentuk termasuk asiklovir poloxamer 188 murni dianalisis karakterisasinya dengan Differential Thermal Analysis (DTA), X-ray Diffraction, Scanning Electron Microscopy (SEM), dan Fourier Transform Infrared (FTIR), kemudian pengambilan dilakukan  (penentuan kadar) mengunakan spektrofotometer UV pada panjang gelombang 257,08 nm dan uji laju disolusi dengan aquadest bebas CO2 menggunakan metode dayung. Hasil pengambilan  (penentuan kadar) menunjukkan bahwa semua formula memenuhi persyaratan farmakope Amerika edisi 30 dan farmakope Indonesia edisi 4 yaitu 95-110%. Sedangkan hasil uji laju disolusi untuk campuran fisik 1: 1, dan dispersi padat 1: 1, dan penggilingan 1: 1 menunjukkan peningkatan yang nyata dibandingkan asiklovir murni. Hal ini juga dapat dilihat dari hasil perhitungan statistik  menggunakan analisis varian satu arah  SPSS 17.

scholarly journals Influence of pretreatment on the properties of α-Fe2O3 and the effect on photocatalytic degradation of methylene blue under visible light

2020 ◽  
Vol 82 (11) ◽  
pp. 2415-2424
Author(s):  
S. Mokhtari ◽  
N. Dokhan ◽  
S. Omeiri ◽  
B. Berkane ◽  
M. Trari
Keyword(s):  
Methylene Blue ◽  
Average Crystallite Size ◽  
Sample Surface ◽  
X Ray Diffraction ◽  
Sem Images ◽  
X Ray ◽  
Lattice Constants ◽  
Electrochemical Pretreatment ◽  
Crystal Properties ◽  
Rhombohedral Symmetry

Abstract The hematite (α-Fe2O3) nanostructures were synthesized by thermal oxidation of metal at 500 °C under atmospheric pressure. We studied the effect of the electrochemical pretreatment of the substrate before calcinations and its impact on the morphology, crystalline structure, lattice microstructural, and optical properties of α-Fe2O3. Uniform nanosheets were observed on the sample surface after calcination; their dimension and morphology were accentuated by the pretreatment, as confirmed by the SEM images. The characteristics of the nanostructures, analyzed by X-ray diffraction (XRD), revealed a rhombohedral symmetry with the space group R-3c and lattice constants: a = 0.5034 nm and c = 1.375 nm. The average crystallite size and strain, determined from the Williamson-Hall (W-H) plot, showed substantial variations after the substrate pretreatment. The Raman spectroscopy confirmed the changes in the crystal properties of the hematite submitted to pretreatment. The diffuse reflectance allowed to evaluate the optical gap which lies between 1.2 and 1.97 eV, induced by the electrochemical processing. The photocatalytic activity of α-Fe2O3 films was assessed by the degradation of methylene blue (MB) under LED light; 15% enhancement of the degradation for the pretreated specimens was noticed.

Structural, Optical, Photocatalytic and Electrochemical Studies of PbS Nanoparticles

2020 ◽  
Vol 61 ◽  
pp. 18-31 ◽  
Author(s):  
Peter A. Ajibade ◽  
Abimbola E. Oluwalana
Keyword(s):  
Particle Sizes ◽  
X Ray Diffraction ◽  
Lead Sulphide ◽  
Electron Transfer Process ◽  
Sem Images ◽  
Pbs Nanoparticles ◽  
X Ray ◽  
Diffusion Controlled ◽  
Reversible Redox ◽  
Diffraction Patterns

Oleic acid (OA) and octadecylamine (ODA) capped lead sulphide (PbS) nanoparticles were prepared at 150, 190 and 230 °C. X-ray diffraction patterns indicates that the synthesized PbS nanoparticles were in the rock cubic salt crystalline phase. The particle sizes of the as-prepared PbS nanoparticles are in the range 2.91–10.05 nm for OA-PbS(150), 24.92–39.98 nm for ODA-PbS(150), 9.26 – 29.08 nm for OA-PbS(190), 34.54 – 48.04 nm for ODA-PbS(190), 17.96–88.07 nm for OA-PbS(230) and 53.60 – 94.42 nm for ODA-PbS(230). SEM images revealed flaky and agglomerated spherical like morphology for the nanoparticles. The energy bandgap of the PbS nanoparticles are in the range 4.14 – 4.25 eV, OA-PbS(230) have the lowest bandgap of 4.14 eV while ODA-PbS(150) have the highest bandgap of 4.25 eV. The PbS nanoparticles were used as photocatalyst for the degradation of Rhodamine B and OA-PbS(150) showed efficiency of 44.11% after 360 mins. Cyclic voltammetry of the PbS nanoparticles showed a reversible redox reaction and linear Randles-Sevcik plots indicates electron transfer process is diffusion controlled.

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