Effects of Silver Doping in the Structural and Optical Properties of Hematite (α-Fe2O3) Synthesized via Chemical Precipitation Method

2021 ◽  
Vol 902 ◽  
pp. 113-118
Author(s):  
Aldrin A. Tan ◽  
Aldwin Christian T. Lacuesta ◽  
Mon Bryan Z. Gili ◽  
Rinlee Butch M. Cervera
Keyword(s):  
Environmental Remediation ◽  
Chemical Precipitation ◽  
Lattice Parameters ◽  
Chemical Precipitation Method ◽  
Precipitation Method ◽  
Bandgap Energy ◽  
Sem Images ◽  
X Ray ◽  
Optical Absorbance ◽  
Vis Spectroscopy

Hematite (α-Fe2O3) is a low-cost n-type semiconductor with significant absorption of visible light owing to its low bandgap energy of 2.1 eV. The wide applications of hematite in renewable energy and environmental remediation continuously entice more studies. However, the low absorbance of solar energy in the UV-range significantly limits the efficiency of many photocatalytic materials. In this study, we tried to dope α-Fe2O3 with silver via chemical precipitation method to lower the bandgap energy and widen its absorbance. The effects of doping hematite with Ag on the structure, morphology, elemental composition, and optical absorbance were determined by characterizing the samples via X-ray diffractometry (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX) analysis, and UV-Vis spectroscopy, respectively. It was observed from the XRD patterns that the α-Fe2O3 crystallizes in hexagonal structure with lattice parameters a = 5.0380 Å and c = 13.7720 Å for the pure α-Fe2O3. Doping with 0.1M and 0.2M AgNO3 leads to a greater value of the lattice parameters indicating successful doping. SEM images show that the hematite formed was composed of particles with irregular shapes that have sizes in the range 0.865-0.883 μm. Excess silver particles were deposited on the surface of hematite. UV-Vis spectra show that there is a red-shift in the absorption band of the Ag-doped hematite. A notable decrease in the bandgap energy of the undoped α-Fe2O3 was observed from ~2.2eV to ~2.0eV with the increase in the amount of the dopant in the hematite as determined using Tauc’s plot.

Synthesis and photocatalytic properties of magnetic separable and recyclable p-n heterojunction CoFe2O4/Bi12O17Cl2 photocatalyst

CrystEngComm ◽  
2021 ◽  
Author(s):  
Kexin Fang ◽  
Lei Shi ◽  
Lishuang Cui ◽  
Chunwei Shi ◽  
Weiwei Si
Keyword(s):  
Chemical Precipitation ◽  
Photocatalytic Properties ◽  
Chemical Precipitation Method ◽  
Precipitation Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
High Crystallinity

A series of CoFe2O4/Bi12O17Cl2 (CFO/Bi12O17Cl2) nanocomposites have been prepared by chemical precipitation method. The result of X-ray diffraction showed that CFO/Bi12O17Cl2 composites had high crystallinity. It was found that CoFe2O4...

Characterisation of undoped Zns and fecl3 doped Zns nanoparticles are synthesized by chemical precipitation method

2020 ◽  
Vol 3 (2) ◽  
Author(s):  
Aarthe K G ◽  
Kiruthika P
Keyword(s):  
Xrd Analysis ◽  
Chemical Precipitation ◽  
Zinc Sulphide ◽  
Chemical Precipitation Method ◽  
Precipitation Method ◽  
Flat Panel Displays ◽  
X Ray Diffraction ◽  
Nano Structure ◽  
X Ray ◽  
Vibrational Bands

Nanoparticles of Ferric chloride (FeCl3) doped Zinc Sulphide (ZnS) and Undoped Zinc Sulphide (ZnS) had been synthesized successfully by simple chemical precipitation method. Particlesizes have been calculated from X-ray diffraction (XRD) analysis which confirms the nano structure of the samples. The Molecular structure of the compound was determined by theFourier transform infrared spectroscopy (FTIR) analysis and the different vibrational bands confirmed the functional groups present in the sample. The bandwidth of the absorbance isexamined by using (UV)-Visible Spectroscopy. The Morphological structures have been confirmed by using Scanning Electron Microscope (SEM). Energy Dispersive analysis of X-ray (EDAX) shows the composition of elements present in the nanoparticles. The applications of ZnS were used in the field such as Field Emitting Diodes (FET), sensors (gas sensors, biosensors), Flat panel displays, Electroluminescence.

Synthesis and characterization of zinc doped copper oxide nanocrystals by chemical precipitation method

2020 ◽  
Vol 3 (2) ◽  
Author(s):  
Aarthe K G ◽  
Sowmiya V
Keyword(s):  
Copper Oxide ◽  
Copper Acetate ◽  
Morphological Structure ◽  
Visible Spectrum ◽  
Chemical Precipitation ◽  
Copper Oxide Nanoparticles ◽  
Chemical Precipitation Method ◽  
Precipitation Method ◽  
X Ray Diffraction ◽  
X Ray

Zinc doped copper oxide nanoparticles were synthesized by chemical precipitation method. Copper acetate is act as a precursor and sodium hydroxide will act as a reducing agent. The prepared nanoparticles were characterized by X-ray diffraction (XRD) which reveals the simple monoclinic structure. The Fourier Transform Infrared Spectroscopy confirms the functional groups present in the nano powders. The morphological Structure of the prepared crystals are analyzed by Scanning Electron Microscopy (SEM) were showed that the products consists of flaky in nature. The Bandwidth of the synthesized sample was calculated by UV- visible spectrum. The presence of compounds in nano powders were confirmed by Energy Dispersive X-ray diffraction (EDAX). Copper oxide has applications as a P-type semiconductor, because it has a narrow band gap of energy of 1.2 e V. Zinc doped copper oxide has applications in the wide variety of fields such as medicine, industries, sunscreens, agriculture etc.

X-Ray Diffraction Analysis of YSAG:Yb Ceramic Powders with Different Stoichiometry

2020 ◽  
Vol 310 ◽  
pp. 1-5
Author(s):  
Marina S. Nikova ◽  
Dmitry S. Vakalov ◽  
Vitaly A. Tarala ◽  
Irina S. Chikulina ◽  
Fedor F. Malyavin ◽  
...  
Keyword(s):  
Diffraction Analysis ◽  
Chemical Precipitation ◽  
Chemical Precipitation Method ◽  
Precipitation Method ◽  
X Ray Diffraction ◽  
Ceramic Powders ◽  
Oxide Composition ◽  
X Ray ◽  
Garnet Phase

Synthesis of YSAG:Yb ceramic powders with different stoichiometry by chemical precipitation method was carried out. It has been established that scandium can replace both dodecahedral and octahedral positions of garnet. It is shown that scandium is embedded in those positions that become available to it when the YAG:Yb composition deviates from stoichiometric. Thus, scandium can compensate for the lack of one of the components of the oxide composition Y2O3, Yb2O3, and Al2O3 during the formation of the garnet phase.

scholarly journals Estimation of Particle Size and Band Gap of Zinc Oxide Nanoparticle Synthesized by Chemical Precipitation Method

2020 ◽  
Vol 41 (1) ◽  
pp. 46-50
Author(s):  
Surendra K. Gautam ◽  
Bibek Sapkota ◽  
Arun Bhujel ◽  
Sitaram Bhattarai
Keyword(s):  
Particle Size ◽  
Zinc Oxide ◽  
Band Gap ◽  
Zno Nanoparticles ◽  
Hexagonal Wurtzite Structure ◽  
Chemical Precipitation ◽  
Chemical Precipitation Method ◽  
Precipitation Method ◽  
X Ray ◽  
Uv Visible

Zinc oxide (ZnO) nanoparticles were synthesized by chemical precipitation method using 0.1M and 0.3M [Zn(NO3)2.6H2O] and Na2CO3 solutions. The particle size and band gap of ZnO nanoparticles were estimated and effect of concentration on it was investigated. The synthesized nanoparticles were characterized by X-ray diffraction (XRD), Transmission electron microscopy (TEM), Energy dispersive X-ray spectroscopy (EDX), Fourier transform infrared spectroscopy (FTIR) and UV-visible spectroscopy. The XRD result revealed that synthesized ZnO nanoparticles have pure hexagonal wurtzite structure and the particle size varies from 27.0 nm to 29.9 nm estimated by using Debye-Scherrer’s equation. The TEM image also projected the average particle size in the range of 20-30 nm and selected area electron diffraction (SAED) further verified the formation of hexagonal wurtzite structure. The FTIR result showed a broad absorption band related to Zn-O vibration band. The UV-visible absorption showed a red shift in the absorption edge with increasing concentration of Zn(NO3)2.6H2O solution. The sizes and band gaps of ZnO nanoparticles increased and decreased, respectively with increasing concentration of Zn(NO3)2.6H2O solution from 0.1M to 0.3M.

scholarly journals Enhanced Visible Light Photocatalytic Degradation of Fe-Doped ZnO Nanoparticles For Organic Dyes

2021 ◽  
Author(s):  
Senthilkumar M ◽  
C. Arunagiri
Keyword(s):  
Photocatalytic Activity ◽  
Visible Light ◽  
Organic Dyes ◽  
Chemical Precipitation ◽  
Precipitation Method ◽  
Photocatalytic Efficiency ◽  
X Ray Diffraction ◽  
X Ray ◽  
Vis Spectroscopy ◽  
Visible Light Photocatalytic

Abstract FexZn1-xO (x = 0, 0.05, 0.075, 0.1 M) nanoparticles based photocatalysts were synthesized by a chemical precipitation method and characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM) with energy dispersive X-ray emission (EDX) and UV–Vis spectroscopy. The photocatalytic efficiency of FexZn1-xO catalysts was assessed under visible light irradiation using the degradation of methylene blue (MB) and methyl orange (MO) dye in aqueous solution. The present investigation shows that the effect of optimized parameters (pH, catalyst dosage and initial dye concentration) and doping concentrations plays significant role in photocatalytic activity. The detailed photocatalytic mechanism for the enhancement of photocatalytic activity has also been proposed.

scholarly journals Synthetic alkaline-earth hydroxyapatites: Influence of their structural, textural, and morphological properties over Co2+ ion adsorption capacity

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Francisco Granados-Correa ◽  
Juan Bonifacio-Martínez
Keyword(s):  
Aqueous Solutions ◽  
Adsorption Capacity ◽  
Alkaline Earth ◽  
High Surface ◽  
Chemical Precipitation ◽  
Chemical Precipitation Method ◽  
Morphological Properties ◽  
Precipitation Method ◽  
Ion Adsorption ◽  
X Ray

Abstract This work addresses the synthesis of nanocrystalline barium, strontium, and calcium hydroxyapatites (Ca-HAps) via the chemical precipitation method, followed by calcination. To give a coherent picture of the most important structural, textural, and morphological properties of these materials and to investigate the influence of these characteristics over Co2+ ion adsorption capacity from aqueous solutions, the powders prepared were systematically characterized by X-ray diffraction, N2-physisorption measurements, scanning electron microscopy (SEM), energy dispersive X-ray spectrometry, and Fourier Transformed Infrared spectroscopy (FTIR). The results clearly showed that the Ca-HAp obtained exhibits better nanocrystallinity, greater structural stability, high surface area, high total pore volume, and mesoporosity, compared with the other synthesized hydroxyapatites, and that these physicochemical properties share a direct correlation with favorable Co2+ ion adsorption capacity at room temperature and pressure. The results proved that the physicochemical features of resulting alkaline-earth hydroxyapatites, prepared via the chemical precipitation method, played a fundamental role during the adsorption of heavy metal (with high toxicity) from aqueous solutions.

Application of cadmium-doped ZnO for the solar photocatalytic degradation of phenol

2019 ◽  
Vol 79 (2) ◽  
pp. 375-385 ◽  
Author(s):  
Behzad Shahmoradi ◽  
Farzaneh Farahani ◽  
Shadi Kohzadi ◽  
Afshin Maleki ◽  
Mohammadamin Pordel ◽  
...  
Keyword(s):  
Photocatalytic Degradation ◽  
Irradiation Time ◽  
Zno Nanorods ◽  
Bandgap Energy ◽  
Phenol Removal ◽  
Operational Parameters ◽  
Sem Images ◽  
X Ray ◽  
Vis Spectroscopy ◽  
Ft Ir

Abstract In this study, photocatalysis of phenol was studied using Cd-ZnO nanorods, which were synthesized by a hydrothermal method. The Cd-ZnO photocatalyst was characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy, and Fourier transform infrared (FT-IR) and UV-Vis spectroscopy. XRD patterns exhibit diffraction peaks indexed to the hexagonal wurtzite structures with the P63mc space group. SEM images showed that the average size of the Cd-ZnO nanorods was about 90 nm. Moreover, the nanorods were not agglomerated and were well-dispersed in the aqueous medium. FT-IR analysis confirmed that a surface modifier (n-butylamine) did not add any functional groups onto the Cd-ZnO nanorods. The dopant used in this study showed reduction of the bandgap energy between valence and conduction of the photocatalyst. In addition, effect of various operational parameters including type of photocatalyst, pH, initial concentration of phenol, amount of photocatalyst, and irradiation time on the photocatalytic degradation of phenol has been investigated. The highest phenol removal was achieved using 1% Cd-ZnO for 20 mg/l phenol at pH 7, 3 g/l photocatalyst, 120 min contact time, and 0.01 mole H2O2.

Synthesis of NiO/CNTs Nanocomposite by Direct Chemical Precipitation Method for Preparation of Voltammetric Sensor in Acetaminophen Analysis

2016 ◽  
Vol 2 (1) ◽  
pp. 17-21
Author(s):  
Elahe Afsharmanesh ◽  
Kiana Jafari ◽  
Mahtab Jabbarzade
Keyword(s):  
Low Cost ◽  
Chemical Precipitation ◽  
Fast Response ◽  
Chemical Precipitation Method ◽  
Precipitation Method ◽  
Voltammetric Sensor ◽  
Carbon Paste ◽  
X Ray ◽  
Correct Dose ◽  
Paste Electrode

Although acetaminophen is a widely used analgesics and antipyretic drug, its overdose leads to many complications. Therefore, determining the correct dose of produced or imported drugs in clinical laboratories or a standard laboratory is essential. Different analytical methods, for example chromatography, spectroscopy and electrochemistry, can be utilized to determine the correct dose of acetaminophen. However, it is believed that electrochemical methods are more efficient due to their fast response and low cost. In this study, we synthesized NiO/CNTs nanocomposite by a direct chemical precipitation method for acetaminophen analysis using a voltammetric sensor. A chemical precipitation method was used for synthesis of NiO/CNTs nanocomposite in the nanoscale. The synthesis of nanopowder was investigated using scanning electron microscopy (SEM) and X-ray powder diffraction. The obtained result confirms the synthesis of nanocomposite with chemical precipitation method with ~35.5 nm diameter for NiO nanoparticle, as established by the Scherrer equation. The results show that the synthesized nanocomposite can modify a carbon paste electrode as a sensor for the analysis of acetaminophen.

STUDY OF STRUCTURAL AND DIELECTRIC PROPERTIES OF COPPER OXIDE NANOPARTICLES PREPARED BY WET CHEMICAL PRECIPITATION METHOD

2013 ◽  
Vol 12 (05) ◽  
pp. 1350036 ◽  
Author(s):  
KIBRIYA SIDDIQUE ◽  
BHABESH KUMAR NATH ◽  
SANJIB KARMAKAR
Keyword(s):  
Electron Microscopy ◽  
Dielectric Properties ◽  
Copper Oxide ◽  
Chemical Precipitation ◽  
Cuo Nanoparticles ◽  
Chemical Precipitation Method ◽  
Precipitation Method ◽  
X Ray ◽  
Wet Chemical ◽  
Wet Chemical Precipitation

We report the synthesis of copper oxide ( CuO ) nanoparticles prepared by wet chemical precipitation method. The structural and dielectric properties are studied by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and complex impedance spectroscopy as a function of frequencies from 40 KHz to 100 KHz in the range of temperatures (308–393K). Maximum value of dielectric constants are found to be in the order of 106 which increases with increase in temperatures. From XRD data it is found that the particle size increases with increase in calcination temperatures. SEM with energy dispersive X-ray fluorescence spectrometer (EDX) results show that only CuO is present in the prepared sample. The selected area electron diffraction (SAED) pattern by TEM shows that uniform size distributions of CuO nanoparticles are present in the sample.

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