UV / visible sol gel W–TiO2 photocatalytic coatings for interior building surfaces

Sol gel indium tin oxide thin films (In: Sn = 90:10) were prepared by the sol-gel dipcoating process on silicon buffer substrate. The precursor solution was prepared by mixing SnCl2.2H2O and InCl3 dissolved in ethanol and acetic acid. The crystalline structure and grain orientation of ITO films were determined by X-ray diffraction. The surface morphology of the films was characterized by scanning electron microscope (SEM). Optical transmission and reflectance spectra of the films were analyzed by using a UV-visible spectrophotometer. The transport properties of majority charge carriers for these films were studied by Hall measurement. ITO thin film with electrical resistivity of 7.6 ×10-3 3.cm, Hall mobility of approximately 2 cm2(Vs)-1 and free carrier concentration of approximately 4.2 ×1020 cm-3 are obtained for films 100 nm thick films. The I-V curve measurement showed typical I-V characteristic behavior of sol gel ITO thin films.

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Epoxy/Silicone Blend Loaded with N-Doped CNT Composites: Study on the Optoelectronic Properties

International Journal of Photoenergy ◽

10.1155/2021/3749722 ◽

2021 ◽

Vol 2021 ◽

pp. 1-11

Author(s):

Younes Ziat ◽

Hamza Belkhanchi ◽

Maryama Hammi ◽

Ousama Ifguis

Keyword(s):

Thin Films ◽

Urbach Energy ◽

Optical Transition ◽

Sol Gel ◽

Visible Range ◽

Visible Spectroscopy ◽

Glass Substrates ◽

Optical Gap ◽

Ito Glass ◽

Uv Visible

Thin films of epoxy/silicone loaded with N-CNT were prepared by a method of sol-gel and deposited on ITO glass substrates at room temperature. The properties of the loaded monolayer samples (0.00, 0.07, 0.1, and 0.2 wt% N-CNTs) were analyzed by UV-visible spectroscopy. The transmittance for the unloaded thin films is 88%, and an average transmittance for the loaded thin film is about 42 to 67% in the visible range. The optical properties were studied from UV-visible spectroscopy to examine the transmission spectrum, optical gap, Tauc verified optical gap, and Urbach energy, based on the envelope method proposed by Swanepoel (1983). The results indicate that the adjusted optical gap of the film has a direct optical transition with an optical gap of 3.61 eV for unloaded thin films and 3.55 to 3.19 eV for loaded thin films depending on the loading rate. The optical gap is appropriately adapted to the direct transition model proposed by Tauc et al. (1966); its value was 3.6 eV for unloaded thin films and from 3.38 to 3.1 eV for loaded thin films; then, we determined the Urbach energy which is inversely variable with the optical gap, where Urbach’s energy is 0.19 eV for the unloaded thin films and varies from 0.43 to 1.33 eV for the loaded thin films with increasing rate of N-CNTs. Finally, nanocomposite epoxy/silicone N-CNT films can be developed as electrically conductive materials with specific optical characteristics, giving the possibility to be used in electrooptical applications.

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Effect of Re and Tm-site on morphology structure and optical band gap of ReTmO3 (Re: La, Ce, Nd, Gd, Dy, Y and Tm: Fe, Cr) prepared by sol-gel method

Revista Mexicana de Física ◽

10.31349/revmexfis.64.381 ◽

2018 ◽

Vol 64 (4) ◽

pp. 381

Author(s):

Muhammad Tufiq Jamil ◽

Javed Ahmad ◽

Syed Hamad Bukhari ◽

Murtaza Saleem

Keyword(s):

Band Gap ◽

Sol Gel ◽

Xrd Analysis ◽

Sem Analysis ◽

X Ray Diffraction ◽

Orthorhombic Crystal ◽

X Ray ◽

Average Grain Size ◽

Auto Combustion ◽

Uv Visible

Rare earth nano sized pollycrystalline orthoferrites and orthocromites ReT mO3 (Re = La, Nd, Gd, Dy, Y and T m = Fe, Cr) have been synthesized by sol-gel auto combustion citrate method. The samples have been characterized by means of X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDX), and UV-visible spectroscopy. The samples are single phase as confirmed by XRD analysis and correspond to the orthorhombic crystal symmetry with space group pbnm. Debye Scherer formula and Williamson Hall analysis have been used to calculate the average grain size which is consistent with that of determined from SEM analysis and varied between 25-75 nm. The elemental compositions of all samples have been checked by EDX analysis. Different crystallographic parameters are calculated with strong structural correlation among Re and Tm sites. The optical energy band gap has been calculated by using Tauc relation estimated to be in the range of 1.77 - 1.87 eV and 2.77 - 3.14 eV, for ReFeO3 and ReCrO3, respectively.

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ZnO-SiO2/Laponite Photocatalyst: Kinetic Study on Photocatalytic Decolorization of Methylene Blue

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.896.541 ◽

2014 ◽

Vol 896 ◽

pp. 541-544

Author(s):

Is Fatimah ◽

N. Nunani Yuyun

Keyword(s):

Methylene Blue ◽

Energy Dispersive Spectrometry ◽

Photocatalytic Performance ◽

Sol Gel ◽

X Ray Diffraction ◽

X Ray ◽

Photocatalytic Decolorization ◽

Uv Visible ◽

Gel Preparation ◽

Adsorption Desorption

ZnO-SiO2/Laponite was prepared by sol-gel preparation procedure consit of SiO2 pillarization to laponite followed by ZnO dispersion by using zinc acetate as precursor. The obtained material was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), diffuse reflectance UV-Visible (DRUV-Vis) and N2 adsorption-desorption analysis. The photocatalytic performance of the amterial in methylene blue decolorization was also investigated. Compared with ZnO-SiO2 nanoparticles, it is concluded that ZnO-SiO2/Laponite possess higher photocatalytic activity which obey Temkin isotherm model.

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Effect of Dip-Coating Cycle on Some Physical Properties of Cu2NiSnS4 Thin Films for Photovoltaic Applications

10.21203/rs.3.rs-194196/v1 ◽

2021 ◽

Author(s):

Ahmed ZITI ◽

Bouchaib HARTITI ◽

Amine BELAFHAILI ◽

Hicham LABRIM ◽

Salah FADILI ◽

...

Keyword(s):

Thin Films ◽

Electron Microscope ◽

Scanning Electron Microscope ◽

Sol Gel ◽

Dip Coating ◽

Visible Spectroscopy ◽

X Ray ◽

Uv Visible ◽

The Impact ◽

Scanning Electron

Abstract Quaternary semiconductor Cu2NiSnS4 thin film was made by the sol-gel method associated to dip-coating technique on ordinary glass substrates. In this paper, we have studied the impact of dip-coating cycle at different cycles: 4, 5 and 6 on the structural, compositional, morphological, optical and electrical characteristics. CNTS thin films have been analyzed by various characterization techniques including: X-ray diffractometer (XRD), Raman measurements, scanning electron microscope (SEM), energy dispersive X-ray spectroscope (EDS), UV-visible spectroscopy and four-point probe method. XRD spectra demonstrated the formation of cubic Cu2NiSnS4 with privileged orientation at (111) plane. Crystallite size of cubic CNTS thin films increase with from 6.30 to 9.52 with dip-coating cycle augmented. Raman scattering confirmed the existence of CNTS thin films by Raman vibrational mode positioned at 332 cm− 1. EDS investigations showed near-stoichiometry of CNTS sample deposited at 5 cycles. Scanning electron microscope showed uniform surface morphologies without any crack. UV-visible spectroscopy indicated that the optical absorption values are larger than 104 cm− 1, Estimated band gap energy of CNTS absorber layers decrease from 1.64 to 1.5 eV with dip-coating cycle increased. The electrical conductivity of CNTS thin films increase from 0.19 to 4.16 (Ω cm)-1. These characteristics are suitable for solar cells applications.

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Sensing Nanoparticulate ZnO with Benzimidazole Derivative by Fluorescence

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.543.63 ◽

2013 ◽

Vol 543 ◽

pp. 63-67

Author(s):

Jayabharathi Jayaraman ◽

Jayamoorthy Karunamoorthy

Keyword(s):

Diffuse Reflectance ◽

Electrochemical Impedance ◽

Fluorescent Sensor ◽

Sol Gel ◽

Benzimidazole Derivative ◽

X Ray Diffraction ◽

X Ray ◽

Uv Visible ◽

Doped Zno ◽

Scanning Electron

A sensitive benzimidazole derivative fluorescent sensor for nanoparticulate ZnO has been designed and synthesized. The nanocrystalline ZnO, Ag doped ZnO and Cu doped ZnO have been synthesised by sol-gel method and characterized by powder X-ray diffraction, scanning electron microscopy (SEM) and UV-visible diffuse reflectance, photoluminescence and electrochemical impedance spectroscopies. The synthesized sensor emits fluorescence at 360 nm and this fluorescence is selectively enhanced by nanocrystalline ZnO. This technique is sensitive to detect and estimate ZnO at micro molar level. Impurities such as Ag and Cu do not hamper the sensitivity of this technique significantly. Keywords: Sensor, SEM, EDX, Impedance, Fluorescence

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Effective Photocatalytic Degradation of Nitrobenzene by Magnetite Modified Titania Composite

Asian Journal of Chemistry ◽

10.14233/ajchem.2021.23137 ◽

2021 ◽

Vol 33 (6) ◽

pp. 1319-1324

Author(s):

E.S. Kunarti ◽

R. Roto ◽

S. Sutarno ◽

I.S. Budi ◽

M. Mardiansyah

Keyword(s):

Reaction Rate ◽

Uv Light ◽

Sol Gel ◽

Solid Material ◽

Reaction Rate Constant ◽

Magnetic Photocatalyst ◽

Uv Light Irradiation ◽

Transmission Electron ◽

Uv Visible ◽

Co Precipitation

Magnetic photocatalyst of magnetite modified titania composite Fe3O4/TiO2 was prepared by co-precipitation and sol-gel methods followed by calcination at 450 ºC. The produced material was confirmed by XRD, FTIR spectrophotometer, vibrating sample magnetometer and transmission electron microscope. The solid material was tested as a photocatalyst for degradation of nitrobenzene under UV light irradiation. The progress of degradation of nitrobenzene was monitored by using a UV-visible spectrophotometer. The photodegradation of nitrobenzene could be best realized at a medium pH of 7 and 120 min of irradiation. The reaction rate constant of nitrobenzene degradation catalyzed by TiO2 and Fe3O4/TiO2 solids were found to be 0.0058 min-1 and 0.0092 min-1, respectively. The photocatalyst was recoverable by use of a magnetic bar and reusable.

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Combined Adsorption and Photocatalytic Degradation for Ciprofloxacin Removal Using Sugarcane Bagasse/N,S-TiO2 Powder Composite

Water ◽

10.3390/w13162300 ◽

2021 ◽

Vol 13 (16) ◽

pp. 2300

Author(s):

Linh Thuy Nguyen ◽

Hanh Thi Nguyen ◽

Khai Manh Nguyen ◽

Thuy Thi Pham ◽

Bart Van der Bruggen

Keyword(s):

Sugarcane Bagasse ◽

Contact Time ◽

Sol Gel ◽

Optimal Conditions ◽

X Ray Diffraction ◽

Initial Concentration ◽

X Ray ◽

Experimental Parameters ◽

Uv Visible ◽

Ciprofloxacin Removal

N,S-TiO2 deposited on three kinds of pre-treated sugarcane bagasse was synthesized via a sol–gel method. The obtained composites were characterized by various techniques, including scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and photoluminescence spectroscopy (PL). UV-visible induced degradation of ciprofloxacin was investigated. The influence of some experimental parameters such as contact time, pH, dosage, and initial concentration on the efficiency of ciprofloxacin elimination was also evaluated. The highest efficiency was observed for the alkaline pre-treated sugarcane bagasse combined with N,S-TiO2, about 86% under optimal conditions (contact time 150-min irradiation, pH 5.5–6, dosage 0.5 g L−1, and the initial concentration CIP 30 ppm). There may be a rapid ciprofloxacin transition from the adsorption site to the photocatalytic site, and the alkaline pre-treated sugarcane bagasse/N,S-TiO2 prevented the recombining of holes and electrons of the photocatalyst. Furthermore, the alkaline pretreatment sugarcane bagasse/N,S-TiO2 composite material was sustainable, with only a 10% reduction after reusing the material three times. The presence of sugarcane bagasse made the material easy to recover from the liquid phase.

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Synthesis, Characterization of α-Al2O3 Nanoparticles and Its Application in Decolorization of Methyl Orange Azo Dye in the Presence of UV Light

Journal of Nanoscience and Technology ◽

10.30799/jnst.192.19050101 ◽

2019 ◽

Vol 5 (1) ◽

pp. 580-583 ◽

Cited By ~ 1

Author(s):

Vijaya P. Dhawale . ◽

Datta J. Late . ◽

Satish D. Kulkarni .

Keyword(s):

Methyl Orange ◽

Contact Time ◽

Uv Light ◽

Sol Gel ◽

Water System ◽

Rhombohedral Structure ◽

Textile Dye ◽

Al2o3 Nanoparticles ◽

Uv Visible ◽

Α Al2o3

Present study deals with the sol-gel synthesis and application of α-Al2O3 nanoparticles (alumina) to decolorize the azo anionic dye methyl orange (MO). α-Al2O3 nanoparticles were successfully synthesized using aluminium oxide, 25% ammonia and polyvinyl alcohol (PVA) were used as low cost raw materials. The properties of synthesized nanoparticles were investigated by using UV-visible spectroscopy, XRD, FTIR, SEM, EDAX, Raman spectroscopy and TEM. From UV–visible spectra, band gap was calculated and it was found to be 3.31 eV. Average crystal size of α-Al2O3 nanoparticles from XRD peaks found to be 25 nm having rhombohedral structure. FTIR spectra reveals that functional groups (O-Al-O) are present. SEM image shows distribution pattern of α-Al2O3 nanoparticles. Chemical composition of α-Al2O3 nanoparticles was confirmed from EDAX spectroscopy measurement. Raman spectra showed crystalline nature of α-Al2O3 nanoparticles. The effect of concentration and pH of dye, dosage of nano adsorbent and contact time were studied. The systematic study shows that, successful color removal of methyl orange dye up to 54% in three hours contact time of pH 4. Hence α-Al2O3 nanoparticles can be used for dye removal from waste water. Industrialization of this technique will be cost effective way to decolorize the textile dye present in water system.

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The effects of surfactant in the sol–gel synthesis of CuO/TiO2 nanocomposites on its photocatalytic activities under UV-visible and visible light illuminations

New Journal of Chemistry ◽

10.1039/c9nj05246a ◽

2020 ◽

Vol 44 (5) ◽

pp. 1888-1904 ◽

Cited By ~ 9

Author(s):

T. N. Ravishankar ◽

M. de O. Vaz ◽

S. R. Teixeira

Keyword(s):

Visible Light ◽

Room Temperature ◽

Low Cost ◽

Sol Gel ◽

Gel Method ◽

Sol Gel Method ◽

Photocatalytic Activities ◽

Uv Visible ◽

Sol Gel Synthesis ◽

Surfactant Assisted

Effective and low-cost CuO/TiO2 nanocomposites were prepared at room temperature by a surfactant-assisted sol–gel method for photocatalytic activities under UV-visible and visible light irradiations.

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