Nanopores and nanosheets of α-Fe2O3 synthetized by electrochemical anodization and analysed by Raman spectroscopy

MRS Advances ◽  
2019 ◽  
Vol 4 (53) ◽  
pp. 2863-2871
Author(s):  
L.M.C. Pérez-Pérez ◽  
A. Báez-Rodríguez ◽  
L. García-González ◽  
J. Hernández-Torres ◽  
O. Velázquez-Camilo ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Crystalline Structure ◽  
Room Temperature ◽  
Ammonium Fluoride ◽  
Deionized Water ◽  
Electrochemical Anodization ◽  
Vibration Modes ◽  
Spectroscopy Technique ◽  
Temperature Scanning ◽  
Static Conditions

Abstract:Nanoparticles and nanopores of iron oxide were synthesized by electrochemical anodization, in an electrolytic medium of ammonium fluoride (NH4F), deionized water and ethylene glycol. After anodization, the Fe foils were annealed at 450 °C for 2 hours. Different anodization times and two concentrations of NH4F (0.1 M and 1.2 M) were evaluated, under static conditions at room temperature. Scanning Electron Microscopy showed nanopores (0.1 M) and nanoparticles (1.2 M). Eight vibration modes characteristic of α-Fe2O3 were found with Raman spectroscopy technique. Relationship between the modes Eu(LO) and 2Eu(LO) was found, therefore, their association with the disorder in the crystalline structure can be determined and it was also found that 2Eu(LO) intensity mode at a concentration of 1.2 M is larger than 0.1 M nanostructures, the FWHM of the A1g mode at 227 cm-1 corresponding to the Fe3+ ions and the Eg at 293 cm-1 mode caused by the O2- ions was also analyzed and founded that the crystalline structure of hematite can be determined by the A1g mode at 227 cm-1.

The Effect of Ultrasonic Treatment on the Morphology and Microstructure of TiO2 Nanotubes Prepared by DC Anodization

2016 ◽  
Vol 860 ◽  
pp. 17-20
Author(s):  
Buagun Samran ◽  
Emmanuel Nyambod Timah ◽  
Udom Tipparach
Keyword(s):  
Surface Morphology ◽  
Ethylene Glycol ◽  
Ultrasonic Treatment ◽  
Room Temperature ◽  
Ammonium Fluoride ◽  
Deionized Water ◽  
Dc Voltage ◽  
Anodization Method

This paper presents the effect of ultrasonic treatment on the morphology and microstructure of TiO2 nanotubes prepared by DC anodization method. The TiO2 nanotubes were grown by one-face anodization at room temperature on titanium sheets of 0.25 mm thickness and 99.7% purity. The electrolyte was composed of ethylene glycol (EG), ammonium fluoride (0.3% wt NH4F) and deionized water (2% V H2O). A constant DC voltage of 50 V was applied during anodization for 2 hours. The samples were ultrasonically cleansed in ethanol for different extended periods of time: 0, 10, 30 and 50 minutes respectively. The samples were annealed at 450 °C for 2 hours. The surface morphology and microstructure of the TiO2 nanotubes formed were studied by XRD and SEM. The best result was obtained when the sampleswere ultrasonicated for 30 minutes.

Preparation of ZnF2 Nano-Particles by Electrochemical Anodization Method

2012 ◽  
Vol 476-478 ◽  
pp. 1616-1620
Author(s):  
Ye Zhang ◽  
Hong Bing Ji
Keyword(s):  
Crystalline Structure ◽  
Applied Voltage ◽  
Room Temperature ◽  
Nano Particles ◽  
Electrochemical Anodization ◽  
Complex Solution ◽  
Anodization Time ◽  
Dominant Component ◽  
Xrd Techniques ◽  
Anodization Method

ZnF2 nano-particles were prepared by electrochemical anodization method at room temperature. Zn foil acted as anode and Pb sheet served as cathode, and the complex solution of NH4F-H2O2-C2H5OH was used as electrolyte. The morphology, composition and crystalline structure of the as-prepared product were characterized by SEM, EDS and XRD techniques. The results showed that the product was rhombic nano-particles with the length of 50-200nm and the width of 50-100nm, the crystalline structure of the product was ZnF2 and ZnO, and the ZnF2 was the dominant component. Effects of NH4F concentration, applied voltage and anodization time on the morphology of the product were investigated.

Effect of Preparation on Microstructure of Ag-Loaded TiO2 Nanotube Arrays

2017 ◽  
Vol 748 ◽  
pp. 155-159
Author(s):  
Somkuan Photharin ◽  
Udom Tipparach
Keyword(s):  
Room Temperature ◽  
Ammonium Fluoride ◽  
Deionized Water ◽  
Nanotube Arrays ◽  
X Ray Diffraction ◽  
X Ray ◽  
Vis Spectroscopy ◽  
Titanium Foils ◽  
Anodization Method ◽  
Scanning Electron

We have synthesyzed TiO2 nanotubes by an anodization method. The cathode was titanium (Ti) sheets and anode was platinum (Pt). The electrolytes were mixtures of ethylene glycol (EG), ammonium fluoride (NH4F) and deionized water (DI water). The anodizing voltage was set to 50 V and the process was carried out for 2 h. The titanium foils were anodized at room temperature. Then Ag nanoparticles were loaded in TiO2 nanotube arrays by immersed in 50 ml solutions containing of AgNO3 (1.0, 1.5 and 2.0 mM) for 24 h. The morphology, structure, and optical properties of the prepared nanotubes were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and and UV-vis spectroscopy (UV-vis) respectively. The structures of TiO2 nanotubes obtained from the nanotube arrays were crystallized by annealing at 450 °C for 2 h before immersed in solution and immersed in solution before crystallized by annealing are similar. When the concentration of silver nitrate (AgNO3) increases, the TiO2 nanotube arrays cracked and are not well arranged.

Preparation and Properties of Cupper and Iron Doped TiO2 Nanotubes by Anodization Method

2017 ◽  
Vol 744 ◽  
pp. 453-457
Author(s):  
Somkuan Photharin ◽  
Udom Tipparach
Keyword(s):  
Room Temperature ◽  
Anatase Phase ◽  
Ammonium Fluoride ◽  
Deionized Water ◽  
Titania Nanotubes ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ordered Arrays ◽  
Vis Spectroscopy ◽  
Anodization Method

We have synthesized titania nanotubes by an anodization method. The anodization was carried out in a two-electrode configuration bath with Ti sheet as the anode and the Pt as the counter electrode. In this experiment, one face of the Ti foils was exposed to the electrolyte during anodization. The electrolytes were mixtures of ethylene glycol (EG), ammonium fluoride (NH4F) and deionized water (DI water) that contained of Cu and Fe dopants of 0.5 mM. The anodizing voltage was set to 50 V and the anodization was performed at room temperature for 2 h. The nanotubes were crystallized by annealing at 450°C for 2 h. The morphology, structure, and optical properties of the prepared nanotubes were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and UV-vis spectroscopy (UV-vis) respectively. The results show that titania nanotubes are anatase phase and the nanotubes are arranged in highly ordered arrays.

scholarly journals Identification of LDPE Grades Focusing on Specific CH2 Raman Vibration Modes

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Richard Jumeau ◽  
Patrice Bourson ◽  
Michel Ferriol ◽  
François Lahure ◽  
Marc Ponçot ◽  
...  
Keyword(s):  
Differential Scanning Calorimetry ◽  
Raman Spectroscopy ◽  
Vibrational Spectroscopy ◽  
Phenomenological Model ◽  
Low Density ◽  
Vibration Modes ◽  
Scanning Calorimetry ◽  
Lamella Thickness ◽  
Poly Ethylene

The possibilities of applications of vibrational spectroscopy techniques (Raman spectroscopy) in the analysis and characterization of polymers are more and more used and accurate. In this paper, our purpose is to characterize Low Density Poly(Ethylene) (LDPE) grades by Raman spectroscopy and in particular with CH2 Raman vibration modes. With temperature measurements, we determine different amorphous and crystalline Raman assignments. From these results and on the basis of the evolution of CH2 bending Raman vibration modes, we develop a phenomenological model in correlation with Differential Scanning Calorimetry and in particular with crystalline lamella thickness determination.

scholarly journals Development of a flow cell based Raman spectroscopy technique to overcome photodegradation in human blood

2019 ◽  
Vol 10 (5) ◽  
pp. 2275 ◽  
Author(s):  
Ben Hansson ◽  
Christian Harry Allen ◽  
Sami Qutob ◽  
Bradford Behr ◽  
Balazs Nyiri ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Human Blood ◽  
Flow Cell ◽  
Spectroscopy Technique

scholarly journals Study of Spectroscopy and Thermodynamic Properties for Phoshours dioxide PO2 Molecular and Influence Study of Bond ( P-O ) on Spectroscopy Properties

2012 ◽  
Vol 9 (4) ◽  
pp. 616-622
Author(s):  
Baghdad Science Journal
Keyword(s):  
Free Energy ◽  
Thermodynamic Properties ◽  
Room Temperature ◽  
Formation Enthalpy ◽  
Heat Of Formation ◽  
Vibration Modes ◽  
Equilibrium Distance ◽  
Atmosphere Pressure ◽  
Gibb’S Free Energy ◽  
Good Agreement

In This research a Spectroscopic complement and Thermodynamic properties for molecule PO2 were studied . That included a calculation of potential energy . From the curve of total energy for molecule at equilibrium distance , for bond (P-O), the degenerated of bond energy was (4.332eV) instate of the vibration modes of ( PO2 ) molecule and frequency that was found active in IR spectra because variable inpolarization and dipole moment for molecule. Also we calculate some thermodynamic parameters of ( PO2 ) such as heat of formation , enthalpy , heat Of capacity , entropy and gibb's free energy Were ( -54.16 kcal/mol , 2366.45 kcal/mol , 10.06 kcal /k/mol , 59.52 kcal /k /mol, -15370.51 kcal / mol ) respectively under condition of room temperature and atmosphere pressure ( 298 k , 1 atm.). We calculate there parameters at various temperature from ( 100 – 3000 ) K . It was found that the obtainded results were in a good agreement with previous experimental facts.

Fizzy water droplets levitate at room temperature

Physics World ◽  
2021 ◽  
Vol 34 (9) ◽  
pp. 7ii-7ii
Author(s):  
Isabelle Dumé
Keyword(s):  
Carbon Dioxide ◽  
Room Temperature ◽  
Deionized Water ◽  
Liquid Droplets ◽  
Water Droplets ◽  
Leidenfrost Effect ◽  
Gaseous Carbon Dioxide

Researchers have come up with a room-temperature way to recreate the Leidenfrost effect and levitate liquid droplets by pumping gaseous carbon dioxide into deionized water.

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