Structural and optical properties of AgCl-sensitized TiO2 (TiO2 @AgCl) prepared by a reflux technique under alkaline condition

Abstract The AgCl-sensitized TiO2 (TiO2@AgCl) has been prepared from the precursor of TiO2-rutile type which on its surface adsorb chloride anion (Cl-) and various amounts of silver using AgNO3 as starting material: AgNO3/(AgNO3+TiO2) mass ratio of 0.00, 1.14, 3.25, 6.38 and 10.32%. Reflux under alkaline condition was the employed technique. All samples were characterized by X-ray diffraction (XRD) and diffuse reflectance UV-vis spectroscopy. The sample without the addition of AgNO3 was analyzed by scanning electron microscope and surface area analyzer. The morphology of the sample showed a distribution of microspheres of approximately 0.5 to 1.0 µm and the specific surface area was 68 m2/g. XRD patterns indicated that the sample without the addition of AgNO3 contained two types of TiO2: rutile (major) and anatase (minor), whereas the samples with the addition of AgNO3 consisted of one phase of AgCl and two types of TiO2: rutile and anatase. The bandgaps of the samples were in the range of 2.97 to 3.24 eV, which were very close to the bandgap of intrinsic TiO2 powder. The presence of 0.8, 2.6 and 4.4 wt% of AgCl in each sample resulted in an additional bandgap in visible light region of 1.90, 1.94 and 2.26 eV, respectively, whereas the presence of 9.4 wt% of AgCl in the sample resulted in two bandgaps in visible light region of 1.98 and 1.88 eV.

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PHOTOCATALYTIC ACTIVITY UNDER VISIBLE LIGHT REGION OF Ca-MODIFIED TiO2NP FILMS PREPARED BY SPARKING OFF Ca-ELECTROPLATED Ti TIPS

Surface Review and Letters ◽

10.1142/s0218625x18400024 ◽

2018 ◽

Vol 25 (Supp01) ◽

pp. 1840002 ◽

Cited By ~ 2

Author(s):

NIDCHAMON JUMRUS ◽

ARISARA PANTHAWAN ◽

TEWASIN KUMPIKA ◽

WATTIKON SROILA ◽

EKKAPONG KANTARAK ◽

...

Keyword(s):

Photocatalytic Activity ◽

Visible Light ◽

Quartz Substrate ◽

Ambient Air ◽

Visible Light Region ◽

Structural And Optical Properties ◽

Uniform Size ◽

Light Region ◽

Vis Spectroscopy ◽

Electroplating Process

In this work, calcium (Ca)-modified titanium dioxide (TiO2) nanoparticulate (NP) films were successfully prepared using sparking off Ca-electroplated Ti tips. Aqueous solution of calcium carbonate (CaCO3) was used as electrolyte in the electroplating process. The experiment was carried out using electric current of 0.02[Formula: see text]mA applied to titanium electrodes for 10[Formula: see text]min. The NP films with small and uniform size were deposited on quartz substrate using the sparking process with a high DC voltage of 4[Formula: see text]kV in ambient air. The as-deposited NP films were then annealed at 800∘C, 900∘C and 1000∘C for 3[Formula: see text]h under atmospheric pressure to improve their crystallinity. Morphology, structural and optical properties of the NP films were characterized by SEM, XRD, Raman, XPS and UV-Vis spectroscopy. The effects of annealing temperature on the properties of the as-deposited and annealed NP films were reported. Furthermore, photocatalytic activity against 10 [Formula: see text]M of methylene blue (MB) under visible light region will be discussed.

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Effects of Synthesis Conditions on the Crystalline Phases and Photocatalytic Activities of Silver Vanadates via Hydrothermal Method

MRS Proceedings ◽

10.1557/proc-1171-s01-08 ◽

2009 ◽

Vol 1171 ◽

Cited By ~ 1

Author(s):

Chao-Ming Huang ◽

Guan T. Pan ◽

Lung C. Chen ◽

C.K. Thomas Yang ◽

Wen S. Chang

Keyword(s):

Photocatalytic Activity ◽

Visible Light ◽

Surface Area ◽

Synthesis Method ◽

Stoichiometric Ratio ◽

X Ray Diffraction ◽

Hydrothermal Conditions ◽

Synthesis Conditions ◽

Vis Spectroscopy ◽

Visible Light Driven

AbstractVisible-light-driven Ag3VO4 photocatalysts were successfully synthesized using low-temperature hydrothermal synthesis method. Under various hydrothermal conditions, the structures of silver vanadates were tuned by manipulating the hydrothermal time and the ratio of silver to vanadium. X-ray diffraction (XRD) results reveal that the powders prepared in a stoichiometric ratio consisted of pure α-Ag3VO4 or mixed phases of Ag4V2O7 and α-Ag3VO4. With increasing the Ag-to-V mole ratio to 6:1, the resulting samples were identified as pure monoclinic structure α-Ag3VO4. UV-vis spectroscopy indicated that silver vanadate particles had strong visible light absorption with associated band gaps in the range of 2.2-2.5 eV. The sample synthesized in the excess silver exhibited higher photocatalytic activity than that synthesized in a stoichiometric ratio. The powder synthesized at silver-rich at 140℃ for 4 h (SHT4) exhibited the highest photocatalytic activity among all samples. The reactivity of SHT4 (surface area, 3.52 m2 g-1) on the decomposition of gaseous benzene was about 16 times higher than that of P25 (surface area, 49.04 m2 g-1) under visible light irradiation. A well developed crystallinity of Ag3VO4 of SHT 4 was considered to enhance the photocatalytic efficiency.

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The Effects of Solvents on the Solvothermal Synthesis of BiVO4 Photocatalyst Powders

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.659.154 ◽

2015 ◽

Vol 659 ◽

pp. 154-158

Author(s):

N. Thanomsri ◽

C. Mongkolkachit ◽

T. Sato ◽

X. Wu ◽

Pornapa Sujaridworakun

Keyword(s):

Heat Treatment ◽

Photocatalytic Activity ◽

Visible Light ◽

Surface Area ◽

X Ray Diffraction ◽

Photo Degradation ◽

X Ray ◽

Structure Surface ◽

Xrd Patterns ◽

Visible Light Photocatalytic

In this study, the effects of different solvents such as ethanol, ethylene glycol, glycerol on the preparation of BiVO4 via solvothermal process, and the influent of calcination heat treatment were studied. The crystal structure, surface area, morphology and optical properties of the obtained BiVO4 particles were investigated by means of X-ray Diffraction (XRD), Brunauer Emmett Teller method (BET), Scanning electron microscope (SEM) and UV-Vis reflectance spectroscopy (UV-Vis DRS), respectively. XRD patterns reveal that all of the obtained BiVO4 samples prepared by solvothermal at 130°C for 4 h have monoclinic structure. The UV-Vis DRS demonstrates that the band gaps of prepared BiVO4 are about 2.38-2.40 eV. The photocatalytic activity was evaluated by photo-degradation of rhodamine B (Rh B) solution under visible light irradiation (λ>420 nm). As the results, the BiVO4 prepared by using ethanol having high crystallinity and surface area showed the highest visible light photocatalytic activity compared to using glycerol and ethylene glycerol, respectively. Furthermore, the photocatalytic activity of BiVO4 prepared by using ethylene glycerol and glycerol could be enhanced by calcination heat treatment at 500°C for 2 h.

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Properties and Photocatalytic Behaviour of Vanadia Loaded Titania Supported on MCM-41 Synthesized using Different Surfactants for Degradation of Methylene Blue

Journal of the Indonesian Chemical Society ◽

10.34311/jics.2020.03.1.28 ◽

2020 ◽

Vol 3 (1) ◽

pp. 28

Author(s):

Yee Khai Ooi ◽

Mohd Hayrie Mohd Hatta ◽

Siew Ling Lee

Keyword(s):

Methylene Blue ◽

Visible Light ◽

Surface Area ◽

Chemical Properties ◽

Carbon Chain ◽

Ammonium Bromide ◽

X Ray Diffraction ◽

Carbon Chains ◽

Xrd Patterns ◽

Mcm 41

An attempt has been carried out to prepare vanadia loaded TiO2 supported on MCM-41(V-TiO2/MCM-41) nanostructured photocatalysts using different surfactants. The surfactants used in the photocatalysts synthesis were dodecyl-trimethyl-ammonium bromide (DTAB), hexadecyl-trimethyl-ammonium bromide (CTAB) and octadecyl-trimethyl-ammonium bromide (STAB) which have varied carbon chains. The effect of crystallinity, surface area and porosity of the MCM-41 support on the physical-chemical properties of synthesized photocatalysts of vanadia loaded TiO2/MCM-41 and their photocatalytic performance were investigated. X-ray diffraction (XRD) patterns showed that the crystallinity of vanadia-TiO2/MCM-41 decreased with increasing of carbon-chain number of the surfactant used. Both surface area and pore volume of V-TiO2 increased significantly from 16.2 m2/g and 0.034 cm3/g to 864.3 m2/g and 0.618 cm3/g, respectively, after being loaded on MCM-41 support which was prepared using CTAB. It was demonstrated that all the V loaded TiO2/MCM-41 materials exhibited remarkable improvement in photocatalytic degradation of methylene blue (MB) under the irradiation of visible light as compared to that of bare TiO2 and V-TiO2. Among these materials, V-TiO2/MCM-41 which was synthesized using CTAB appeared to be the best photocatalyst with 57% of MB removal under visible light irradiation.

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Structural and optical properties of KNN nanocubes synthesized by a green route using gelatin

Functional Materials Letters ◽

10.1142/s1793604715500307 ◽

2015 ◽

Vol 08 (02) ◽

pp. 1550030 ◽

Cited By ~ 6

Author(s):

Gh. H. Khorrami ◽

A. Kompany ◽

A. Khorsand Zak

Keyword(s):

Optical Properties ◽

Sol Gel ◽

Structural Deformation ◽

X Ray Diffraction ◽

Structural And Optical Properties ◽

Transmission Electron ◽

Green Route ◽

Vis Spectroscopy ◽

Xrd Patterns ◽

Average Size

Sodium potassium niobate nanoparticles [( K 0.5 Na 0.5) NbO 3, KNN ], KNN-NPs, were synthesized using a modified sol–gel method. Structural and optical properties of the prepared samples were investigated by thermogravometric analyzer (TGA), X-ray diffraction (XRD), transmission electron microscopy (TEM), Raman and UV–Vis spectroscopy. The XRD patterns showed that the formation of the orthorhombic KNN-NPs starts at 500°C calcination temperature. Raman spectroscopy was used to investigate the crystalline symmetry and the structural deformation of the prepared KNN-NPs. TEM images showed that the morphology of the prepared particles is cubic, with the average size of about 50 nm. From diffused reflectance spectroscopy along with using Kubelka–Munk method, the energy bandgaps were determined to be indirect with the values of 3.13 eV and 3.19 eV for the samples calcined at 500°C and 600°C, respectively.

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Influence of Calcination Temperature towards Fe-TiO2 for Visible-Driven Photocatalyst

Materials Science Forum ◽

10.4028/www.scientific.net/msf.888.435 ◽

2017 ◽

Vol 888 ◽

pp. 435-440 ◽

Cited By ~ 6

Author(s):

Siti Aida Ibrahim ◽

Muhamad Nazim Ahmid

Keyword(s):

Visible Light ◽

Calcination Temperature ◽

Sol Gel ◽

X Ray Diffraction ◽

Combined Method ◽

Calcination Process ◽

Calcination Temperatures ◽

Light Region ◽

Average Grain Size ◽

Vis Spectroscopy

TiO2 is one of the most promising photocatalysts that is widely used for environmental clean-up due to its ability to degrade organic pollutants in air or water. The purpose of this study is to enhance the photocatalytic activity of TiO2 by absorbing energy in visible light region in order to degrade pollutants. In this study, the nanostructured Fe-TiO2 was successfully synthesised via a combined method of sol-gel and calcination process. The calcination temperatures used varied from 400 to 800 °C. The as-prepared samples were characterized by X-ray diffraction (XRD), FESEM and UV-Vis spectroscopy (UV-Vis). XRD results show that the phases of TiO2 are dependent on calcination temperature. It is found that both TiO2 and Fe-TiO2 phases were transformed from anatase to rutile as the temperatures were increased. FESEM images revealed that the particle size was agglomerated and the average grain size was about 54 to 66 nm. UV-Vis analysis indicated that the incorporation of Fe and varied calcination temperature may affect the optical properties as the absorption profile was shifted from 445 nm to 585 nm. Thus, this results show that Fe-TiO2 is a highly potential photocatalyst to degrade pollutants under visible light irradiation.

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Synthesis of Fe3O4/MIL-101 material and evaluation of photocatytic activity

Vietnam Journal of Catalysis and Adsorption ◽

10.51316/jca.2020.047 ◽

2020 ◽

Vol 9 (3) ◽

pp. 40-44

Author(s):

Kim Nguyen Van ◽

Thanh Huynh Thi Minh

Keyword(s):

Visible Light ◽

Visible Light Region ◽

X Ray Diffraction ◽

Visible Absorption ◽

X Ray ◽

Light Region ◽

Uv Visible ◽

Absorption Spectrometer ◽

Scanning Electron

In the present work, results synthesis of Fe3O4/MIL-101 material and evaluation of photocatytic activity under visible light region. Characterization of Fe3O4/MIL-101 was investigated by using techniques including X-ray diffraction pattern (XRD), scanning electron microscopy (SEM), IR spectra and UV-visible absorption spectrometer. Evaluation of the photocatalytic activity of Fe3O4/MIL-101 material on the conversion of blue methylen solution under degradation in the visible light region.

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Fabrication of V-Doped TiO2 Nanoparticles and Photocatalytic Studies under Visible Light

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.634-638.2180 ◽

2013 ◽

Vol 634-638 ◽

pp. 2180-2183 ◽

Cited By ~ 1

Author(s):

Jun Bo Guo ◽

Zhang Hua Gan ◽

Jing Liu ◽

Zhi Hong Lu

Keyword(s):

Visible Light ◽

Sol Gel ◽

Synergetic Effect ◽

X Ray Diffraction ◽

Electron Hole ◽

Optimal Doping ◽

X Ray ◽

Light Region ◽

Vis Spectroscopy ◽

Optimal Doping Concentration

The V-doped TiO2 nanoparticles were successfully prepared by sol-gel method and characterized by X-ray diffraction (XRD), UV-vis spectroscopy and photoluminescence (PL) spectroscopy respectively. It is found that doping V can shift the absorption edge to the visible light region and decrease the recombination of photo-induced electron-hole pairs. Then the photo-absorption and photocatalytic activity were greatly improved. The optimal doping concentration is 0.5% due to synergetic effect of the recombination of electron-hole pairs and adsorption of dyes molecules at the surface of samples.

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