scholarly journals Photocatalytic Degradation of Nitro and Chlorophenols Using Doped and Undoped Titanium Dioxide Nanoparticles

2011 ◽  
Vol 2011 ◽  
pp. 1-8 ◽  
Author(s):  
Hassan Ilyas ◽  
Ishtiaq A. Qazi ◽  
Wasim Asgar ◽  
M. Ali Awan ◽  
Zahir-ud-din Khan
Keyword(s):  
Photocatalytic Degradation ◽  
Crystallite Size ◽  
Model Compound ◽  
Titanium Dioxide Nanoparticles ◽  
Xrd Analysis ◽  
Scanning Electron Micrographs ◽  
X Ray Diffraction ◽  
X Ray ◽  
Liquid Impregnation ◽  
Scanning Electron

Pure and Ag-TiO2nanoparticles were synthesized, with the metallic doping being done using the Liquid Impregnation (LI) method. The resulting nanoparticles were characterized by analytical methods such as scanning electron micrographs (SEMs), Energy Dispersive Spectroscopy (EDS), and X-ray diffraction (XRD). XRD analysis indicated that the crystallite size ofTiO2was 27 nm to 42 nm while the crystallite size of Ag-TiO2was 11.27 nm to 42.52 nm. The photocatalytic activity of pureTiO2and silver dopedTiO2was tested by photocatalytic degradation ofp-nitrophenol as a model compound. Ag-TiO2nanoparticles exhibited better results (98% degradation) as compared to pureTiO2nanoparticles (83% degradation) in 1 hour for the degradation ofp-nitrophenol. Ag-TiO2was further used for the photocatalytic degradation of 2,4-dichlorphenol (99% degradation), 2,5-dichlorophenol (98% degradation), and 2,4,6-trichlorophenol (96% degradation) in 1 hour. The degree of mineralization was tested by TOC experiment indicating that 2,4-DCP was completely mineralized, while 2,5-DCP was mineralized upto 95 percent and 2,4,6-TCP upto 86 percent within a period of 2 hours.

scholarly journals Enhancement of photocatalytic activity of TiO2 nanoparticles by silver doping: photodeposition versus liquid impregnation methods

2013 ◽  
Vol 10 (1) ◽  
pp. 1-7 ◽  
Keyword(s):  
Photocatalytic Activity ◽  
Photocatalytic Degradation ◽  
Tio2 Nanoparticles ◽  
Model Compound ◽  
Scanning Electron Micrographs ◽  
X Ray Diffraction ◽  
Electron Hole ◽  
Doped Tio2 ◽  
Liquid Impregnation ◽  
Positive Effect

Silver doped TiO2 nanoparticles have been prepared by liquid impregnation (LI) and photodeposition (PD) methods and characterized by surface analytical methods such as scanning electron micrographs (SEM) and X-ray diffraction (XRD). The photocatalytic activity of silver doped TiO2 was tested by photocatalytic degradation of C.I. Acid Red 88 (AR88) as a model compound from monoazo textile dyes. Results show silver doped TiO2 is more efficient than undoped TiO2 at photocatalytic degradation of AR88. The positive effect of silver on the photoactivity of TiO2 at degradation of AR88 may be explained by its ability to trap electrons. This process reduces the recombination of light generated electron-hole pairs at TiO2 surface. Silver content has an optimum value 2% in LI and 0.5% in PD methods for achieving high photocatalytic activity. The AR88 decomposition with Ag-photodeposited method was much higher than that of deposited with LI method.

Modification of Pb-Sb eutectic bearing-solder alloys with bismuth additions rapidly solidified from melt

2015 ◽  
Vol 10 (1) ◽  
pp. 2523-2533
Author(s):  
Rizk El- Sayed ◽  
Bilal W. Mahdi ◽  
Abu-Bakr El-Bediwi ◽  
Mustafa Kamal
Keyword(s):  
Melt Spinning ◽  
Xrd Analysis ◽  
Ternary Alloys ◽  
Scanning Electron Micrographs ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Binary Eutectic ◽  
Lower Melting Point ◽  
Scanning Electron

In this work, various amounts of Bi element have been added to the eutectic Pb-Sb to form bearing- solder materials. The Pb-Sb eutectic has been produced by rapid solidification using melt spinning technique with various amounts of Bi have been added to it, in the ratio 1, 2 , 3, 4, and 5 wt.%. Scanning electron microscopy (SEM), X- ray diffraction (XRD) analysis and differential scanning calorimetry (DSC) have been carried out.  Microhardness measurements were also carried out using Vicker’s hardness technique.  The results showed that, the ternary alloys up to 4 wt.% Bi  have properties superior to binary eutectic material.   Bismuth up to 4wt. % increases the Young’s modulus, Vicker’s hardness and decreases the electrical resistivity, internal friction and melting point.  The ternary Pb-13.1Sb-4Bi solder alloy has a lower melting point about 237.87 ˚C. Also, the results show that formation of Bi phase developed the mechanical properties and Vicker’s hardness due to addition of Bi element.   The addition of Bi refines the crystal size of Sn in case of melt spun alloys as seen in scanning electron micrographs and X-ray diffraction.

scholarly journals Photocatalytic Degradation of 2,4,6-Trichlorophenol by MgO–MgFe2O4 Derived from Layered Double Hydroxide Structures

Catalysts ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. 454 ◽  
Author(s):  
Esthela Ramos-Ramírez ◽  
Francisco Tzompantzi-Morales ◽  
Norma Gutiérrez-Ortega ◽  
Héctor G. Mojica-Calvillo ◽  
Julio Castillo-Rodríguez
Keyword(s):  
Photocatalytic Degradation ◽  
Layered Double Hydroxides ◽  
X Ray Diffraction ◽  
Application Study ◽  
Toxic Compounds ◽  
X Ray ◽  
Thermally Activated ◽  
Double Hydroxide ◽  
Double Hydroxides ◽  
Scanning Electron

In recent years, the search for solutions for the treatment of water pollution by toxic compounds such as phenols and chlorophenols has been increasing. Phenols and their derivatives are widely used in the manufacture of pesticides, insecticides, paper, and wood preservers, among other things. Chlorophenols are partially biodegradable but not directly photodegradable by sunlight and are extremely toxic—especially 2,4,6-trichlorophenol, which is considered to be potentially carcinogenic. As a viable proposal to be applied in the treatment of water contaminated with 2,4,6-trichlorophenol, this paper presents an application study of the thermally activated Mg/Fe layered double hydroxides as photocatalysts for the mineralization of this contaminant. Activated Mg/Fe layered double hydroxides were characterized by X-ray diffraction, thermal analysis, N2 physisorption, and scanning electron microscopy with X-ray dispersive energy. The results of the photocatalytic degradation of 2,4,6-trichlorophenol in aqueous solution showed good photocatalytic activity, with an efficiency of degradation of up to 93% and mineralization of 82%; degradation values which are higher than that of TiO2-P25, which only reached 18% degradation. The degradation capacity is attributed to the structure of the MgO–MgFe2O4 oxides derived from double laminate hydroxide Mg/Fe. A path of degradation based on a mechanism of superoxide and hollow radicals is proposed.

scholarly journals EFFECT OF OPERATIONAL PARAMETER ON PHOTOCATALYTIC DEGRADATION OF OXAMYL PESTICIDE

2020 ◽  
Vol 4 (12) ◽  
pp. 74-84
Author(s):  
Brijesh Pare ◽  
Satish Piplode ◽  
Vaishali Joshi
Keyword(s):  
Photocatalytic Activity ◽  
Photocatalytic Degradation ◽  
Room Temperature ◽  
Light Irradiation ◽  
Solar Light ◽  
X Ray Diffraction ◽  
Operational Parameter ◽  
X Ray ◽  
Solar Light Irradiation ◽  
Scanning Electron

Flower like bismuth oxy chloride (BiOCl) was successfully synthesized by a simple hydrolytic method at room temperature. The precursor and as-prepared samples were characterized by X-ray diffraction (XRD), High Resolution Field Emission Scanning Electron Microscope (HR FESEM). The results indicated that the as-prepared BiOCl sample is self-assembled hierarchically with nano sheets. The photocatalytic activity of BiOCl was tested on the degradation of the Oxamyl (OM) under solar light irradiation. The results showed that pesticide molecules could be efficiently degraded over BiOCl under solar light irradiation. All the experiment were carried out in the following reaction condition, [OM] = 10-4 mol dm-3, BiOCl NPs= 40mg/50ml, pH= 6.3. Effect of operational parameter such as concentration of H2O2, K2S2O8, FeCl3, Fenton’s reagent (Fe3+/H2O2) and N2, O2 purging on the photocatalytic degradation was observed.

scholarly journals Solvothermally derived Me2(H2O)4(5SSA)3·DMF and Me2(H2O)4(4NSA)2·DMF: Application as Biginelli reaction catalysts

Chemija ◽  
2019 ◽  
Vol 30 (2) ◽  
Author(s):  
Andrius Laurikėnas ◽  
Fatma Yalçin ◽  
Robertas Žilinskas ◽  
Ayse Uztetik Morkan ◽  
Albinas Žilinskas ◽  
...  
Keyword(s):  
Solvothermal Synthesis ◽  
Catalytic Properties ◽  
Inorganic Compounds ◽  
Biginelli Reaction ◽  
Xrd Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Hybrid Compounds ◽  
Phase And Chemical Composition ◽  
Scanning Electron

The solvothermal synthesis between Me(NO3)x ∙ yH2O (Mex+ = Fe3+, Ni2+, Mn2+, Co2+, Cu2+) and respectively 4-nitrosalycilic (4NSA) and 5-sulfosalicylic (5SSA) acids produced hybrid organic-inorganic compounds composed of Mex+ ions and organic fragments which include three different functional groups, carboxylic, hydroxyl and sulfonic, each coordinated to the Mex+ ions. The phase and chemical composition, microstructure and properties of Me2(H2O)4(5SSA)3·DMF and Me2(H2O)4(4NSA)2·DMF (DMF – dimethylformamide) hybrid compounds were evaluated and discussed. The synthesised materials were characterised by X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM) and nuclear magnetic resonance (NMR) spectroscopy. The catalytic properties of the obtained compounds were also investigated.

Synthesis, Structural Analysis of Cadmium Sulphide Nanocrystallites

2019 ◽  
Vol 969 ◽  
pp. 169-174
Author(s):  
R. Sivanand ◽  
S. Chellammal ◽  
S. Manivannan
Keyword(s):  
Size Variation ◽  
Cadmium Sulphide ◽  
Xrd Analysis ◽  
Sem Analysis ◽  
Precipitation Method ◽  
Capping Agent ◽  
Energy Dispersive Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Scanning Electron

In this paper, the effect of size variation of cadmium sulphide nanocrystallites which have been prepared by precipitation method is analyzed. These prepared samples were studied using X-ray diffraction (XRD), Scanning electron microscopy (SEM), and Energy dispersive analysis of spectroscopy (EDAX) techniques. SEM analysis represents the morphological nature of prepared samples and EDAX indicates the confirmation of elements present in the sample. XRD analysis determines the size of the samples and identifies the structure using miller indices (h k l values) of the nanocrystallies matches with JCPDS. From the XRD analysis, the size variation which depends on dopant, capping agent are discussed and corresponding results are reported in this paper.

Microstructural Characterization of Glass-to-Metal Brazed Joint

2012 ◽  
Vol 616-618 ◽  
pp. 1732-1735 ◽  
Author(s):  
Xi Hai Shen ◽  
Yu Gang Zheng ◽  
Liang Chang ◽  
Jin Jia Guo ◽  
Song Bin Ye ◽  
...  
Keyword(s):  
Thermal Power ◽  
Microstructural Characterization ◽  
Xrd Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Solar Thermal Power ◽  
Brazed Joints ◽  
Brazed Joint ◽  
Scanning Electron

Aiming at the glass-to-metal seals serving in the Solar Thermal Power (STP), glass-to-metal vacuum brazed joints were studied. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis were performed to examine the microstructure and element contents of interface seam on the glass-to-metal vacuum brazed joints. Also, the compositional concentration of the interface seam was measured by using energy dispersive spectroscopy (EDS).

The Effect of Water Content on the Formation of TiO2 Nanotubes in Ethylene Glycol

2010 ◽  
Vol 173 ◽  
pp. 102-105 ◽  
Author(s):  
Khairul Arifah Saharudin ◽  
Srimala Sreekantan
Keyword(s):  
Crystal Structure ◽  
Aspect Ratio ◽  
Ethylene Glycol ◽  
Water Content ◽  
Anatase Phase ◽  
Xrd Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Degradation Of Methyl Orange ◽  
Scanning Electron

In this paper, anodization of Ti foil was carried out in ethylene glycol (EG) containing 5 wt% NH4F solution and 0 to 1.5 wt% of water at 50 V for 60 min. The pH of the bath was kept constant at ~pH7. The crystal structure was studied by X-Ray Diffraction (XRD) analysis, and the morphology was observed via field emission scanning electron microscopy (FESEM). TiO2 nanotube with aspect ratio of 100 was obtained in EG containing less than 1wt % water. The nanotubes wall was very smooth. Increasing the water content > 1wt % results in short nanotubes of approximately 6.2μm with aspect ratio of 62. As anodized, nanotubes were amorphous and annealed at 400 °C promote 100 % anatase phase. Photocatalytic activity of the nanotubes produced at different water content was also evaluated by the degradation of methyl orange and the detail of the observation was discussed thoroughly in this paper.

Interaction between Yttria Fully Stabilized Zirconia or Yttria-Zirconia Blended Face-Coat with Ti6Al4V during Investment Casting

2014 ◽  
Vol 1019 ◽  
pp. 302-310 ◽  
Author(s):  
Kalenda Mutombo ◽  
Christina Kgomo ◽  
P. Rossouw
Keyword(s):  
Electron Microscopy ◽  
Xrd Analysis ◽  
Experimental Results ◽  
X Ray Diffraction ◽  
Stabilized Zirconia ◽  
X Ray ◽  
Hardness Tester ◽  
Alpha Case ◽  
Face Coat ◽  
Scanning Electron

The interaction between the Ti6Al4V alloy and the mould materials was investigated. The alpha-case was characterized by Vickers hardness tester, optical and scanning electron microscopy equipped with electron dispersive X-ray spectrometry (EDX). X-ray diffraction (XRD) analysis was performed on as cast and on YFSZ or YZ-Blended face-coats. From the experimental results, a distinct alpha-case formation was revealed. The YFSZ led to a thicker and harder alpha-case than the YZ-Blended face-coat. The EDX revealed the presence of Zr and Si elements in both alpha-cases. Therefore, from experimental results and thermodynamic calculations, pure ZrO2and SiO2may react with Ti.

Using X-ray diffraction for studying the effect of modulation and machining parameters on deformation level in brass particulate produced by modulation assisted machining

2013 ◽  
Vol 28 (S2) ◽  
pp. S315-S326 ◽  
Author(s):  
Ravinder Singh Joshi ◽  
Harpreet Singh
Keyword(s):  
Electron Microscope ◽  
Aspect Ratio ◽  
Crystallite Size ◽  
Internal Strain ◽  
Machining Parameters ◽  
X Ray Diffraction ◽  
X Ray ◽  
Different Shapes ◽  
Deformation Level ◽  
Scanning Electron

In present investigation, effect of modulation and machining parameters on deformation level of the chips produced during modulation assisted machining (MAM) has been studied. It is shown that disruption in tool-chip contact during modulation assisted machining helps in the formation of discrete chips. Size and shape of the particles produced in MAM can be controlled by varying modulation and machining conditions. Particulates of different shapes and sizes ranging from 100 µm to 5 mm with an aspect ratio of ~10 were produced using MAM. The morphology of the particulates produced was characterized by scanning electron microscope (SEM). Deformation in chip particulates was investigated using X-Ray diffraction. The crystallite size and internal strain in particulates were evaluated using Scherrer and Williamson-Hall methods respectively. The crystallite size of the particulates was found to decrease with decrease in their size, whereas internal strain in particulates was observed to increase with decrease in their size. Furthermore, the length of particulates was observed to decrease with an increase in the ratio of frequency of modulation (fm) to frequency of workpiece rotation (fw). However, the corresponding change in microstrain and crystallite size was insignificant with change in this ratio.

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