Improved Visible Light Photocatalytic Activity for TiO2Nanomaterials by Codoping with Zinc and Sulfur

S/Zn codoped TiO2nanomaterials were synthesized by a sol-gel method. X-ray diffraction, UV-vis diffuse reflectance spectroscopy, transmission electron microscopy, photoluminescence spectroscopy, and X-ray photoelectron spectroscopy were used to characterize the morphology, structure, and optical properties of the prepared samples. The introduction of Zn and S resulted in significant red shift of absorption edge for TiO2-based nanomaterials. The photocatalytic activity was evaluated by degrading reactive brilliant red X-3B solution under simulated sunlight irradiation. The results showed S/Zn codoped TiO2exhibited higher photocatalytic activity than pure TiO2and commercial P25, due to the photosynergistic effect of obvious visible light absorption, efficient separation of photoinduced charge carriers, and large surface area. Moreover, the content of Zn and S in the composites played important roles in photocatalytic activity of TiO2-based nanomaterials.

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Visible-Light-Induced Photocatalytic Activity of Boron-Doped BiVO4

Materials Science Forum ◽

10.4028/www.scientific.net/msf.809-810.890 ◽

2014 ◽

Vol 809-810 ◽

pp. 890-894

Author(s):

Dan Li ◽

Lian Wei Shan ◽

Gui Lin Wang ◽

Li Min Dong ◽

Wei Li ◽

...

Keyword(s):

Photocatalytic Activity ◽

Visible Light ◽

Diffuse Reflectance ◽

Diffuse Reflectance Spectroscopy ◽

Sol Gel ◽

Reflectance Spectroscopy ◽

Scheelite Structure ◽

X Ray Diffraction ◽

X Ray ◽

Boron Doped

Boron-BiVO4 samples were synthesized by sol-gel method. They were characterized by UV-vis diffuse reflectance spectroscopy, X-ray diffraction. Photocatalytic activity of the obtained BiVO4 samples was investigated through degrading methylene blue (MB). The results reveal that boron-BiVO4 catalysts have monoclinic scheelite structure. The BiVO4 and Co-BiVO4 photocatalysts were responsive to visible light. Co-BiVO4 photocatalyst showed higher photocatalytic activity than pure BiVO4, resulting in the significantly improved efficiency of degradation of MB.

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FeYO3@rGO nanocomposites: Synthesis, characterization and application in photooxidative degradation of atrazine under visible light

Materials Express ◽

10.1166/mex.2021.1957 ◽

2021 ◽

Vol 11 (5) ◽

pp. 706-716

Author(s):

Nada D. Al-Khthami ◽

Tariq Altalhi ◽

Mohammed Alsawat ◽

Mohamed S. Amin ◽

Yousef G. Alghamdi ◽

...

Keyword(s):

Visible Light ◽

Photoelectron Spectroscopy ◽

Sol Gel ◽

Bandgap Energy ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Reduced Graphene ◽

Structural Surface ◽

Adsorption Desorption

Different organic pollutants have been remediated photo catalytically by applying perovskite photocatalysts. Atrazine (ATR) is a pesticide commonly detected as a pollutant in drinking, surface and ground water. Herein, FeYO3@rGO heterojunction was synthesized and applied for photooxidation decomposition of ATR. First, FeYO 3nanoparticles (NPs) were prepared via routine sol-gel. After that, FeYO3 NPs were successfully incorporated with different percentages (5, 10, 15 and 20 wt.%) of reduced graphene oxide (rGO) in the synthesis of novel FeYO3@rGO photocatalyst. Morphological, structural, surface, optoelectrical and optical characteristics of constructed materials were identified via X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Transmission electron microscopy (TEM), adsorption/desorption isotherms, diffusive reflectance (DR) spectra, and photoluminescence response (PL). Furthermore, photocatalytic achievement of the constructed materials was evaluated via photooxidative degradation of ATR. Various investigations affirmed the usefulness of rGO incorporation on the advancement of formed photocatalysts. Actually, novel nanocomposite containing rGO (15 wt.%) possessed diminished bandgap energy, as well as magnified visible light absorption. Furthermore, such nanocomposite presented exceptional photocatalytic achievement when exposed to visible light as ATR was perfectly photooxidized over finite amount (1.6 g · L-1) from the optimized photocatalyst when illuminated for 30 min. The advanced photocatalytic performance of constructed heterojunctions could be accredited mainly to depressed recombination amid induced charges. The constructed FeYO3@rGO nanocomposite is labelled as efficient photocatalyst for remediation of herbicides from aquatic environments.

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Hydrothermal Synthesis of Iodine-Doped Nanoplates with Enhanced Visible and Ultraviolet-Induced Photocatalytic Activities

International Journal of Photoenergy ◽

10.1155/2012/915386 ◽

2012 ◽

Vol 2012 ◽

pp. 1-12 ◽

Cited By ~ 5

Author(s):

Jiang Zhang ◽

Zheng-Hong Huang ◽

Yong Xu ◽

Feiyu Kang

Keyword(s):

Photocatalytic Activity ◽

Photoelectron Spectroscopy ◽

Oxygen Vacancies ◽

Diffuse Reflectance Spectroscopy ◽

Synergetic Effect ◽

X Ray Diffraction ◽

X Ray ◽

Selected Area Electron Diffraction ◽

Transmission Electron ◽

Photocatalytic Activities

The iodine-doped Bi2WO6(I-BWO) photocatalyst was prepared via a hydrothermal method using potassium iodide as the source of iodine. The samples were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM) and selected area electron diffraction (SAED), X-ray photoelectron spectroscopy (XPS), UV-vis diffuse reflectance spectroscopy (DRS), and photoluminescence (PL) spectroscopy. The photocatalytic activity of I-BWO for the degradation of rhodamine B (RhB) was higher than that of pure BWO and I2-BWO regardless of visible light (>420 nm) or ultraviolet light (<400 nm) irradiation. The results of DRS analysis showed that the I-BWO and I2-BWO catalysts had narrower band gaps. XPS analysis proved that the multivalent iodine species including I0and were coadsorbed on the defect surface of Bi2WO6in I-BWO. The enhanced PL intensity revealed that a large number of defects of oxygen vacancies were formed by the doping of iodine. The enhanced photocatalytic activity of I-BWO for degradation of RhB was caused by the synergetic effect of a small crystalline size, a narrow band gap, and plenty of oxygen vacancies.

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Photocatalytic Performance of SiO2/CNOs/TiO2 to Accelerate the Degradation of Rhodamine B under Visible Light

Nanomaterials ◽

10.3390/nano9121671 ◽

2019 ◽

Vol 9 (12) ◽

pp. 1671 ◽

Cited By ~ 2

Author(s):

Weike Zhang ◽

Yanrong Zhang ◽

Kai Yang ◽

Yanqing Yang ◽

Jia Jia ◽

...

Keyword(s):

Photocatalytic Activity ◽

Visible Light ◽

Rhodamine B ◽

Photoelectron Spectroscopy ◽

Degradation Rate ◽

Photocatalytic Performance ◽

Sol Gel ◽

X Ray Diffraction ◽

X Ray ◽

Electronic Microscope

A silicon dioxide/carbon nano onions/titanium dioxide (SiO2/CNOs/TiO2) composite was synthesized by a simple sol-gel method and characterized by the methods of X-ray diffraction (XRD), scanning electronic microscope (SEM), X-ray photoelectron spectroscopy (XPS), Brunauer–Emmett–Teller (BET), Fourier transform infrared (FTIR), thermogravimetric analysis (TG), differential scanning calorimeter (DSC) and UV-Vis diffuse reflectance spectra (UV-Vis DRS). In this work, the photocatalytic activity of the SiO2/CNOs/TiO2 photocatalyst was assessed by testing the degradation rate of Rhodamine B (RhB) under visible light. The results indicated that the samples exhibited the best photocatalytic activity when the composite consisted of 3% CNOs and the optimum dosage of SiO2/CNOs/TiO2(3%) was 1.5 g/L as evidenced by the highest RhB degradation rate (96%). The SiO2/CNOs/TiO2 composite greatly improved the quantum efficiency of TiO2. This work provides a new option for the modification of subsequent nanocomposite oxide nanoparticles.

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Preparation of g-C3N4/MoS2 Composite Material and Its Visible Light Catalytic Performance

10.21203/rs.3.rs-627855/v1 ◽

2021 ◽

Author(s):

Yu Fan ◽

Yan-ning Yang ◽

Chen Ding

Keyword(s):

Electron Microscopy ◽

Photocatalytic Activity ◽

Visible Light ◽

Photoelectron Spectroscopy ◽

Photogenerated Electron ◽

Catalytic Performance ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Calcination Method

Abstract The g-C3N4 nanosheet was prepared by calcination method, the MoS2 nanosheet was prepared by hydrothermal method. The g-C3N4/MoS2 composites were prepared by ultrasonic composite in anhydrous ethanol. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), ultraviolet-visible spectroscopy (UV-Vis), and photoluminescence (PL) techniques were used to characterize the materials. The photocatalytic degradation of Rhodamine B (Rh B) by g-C3N4/MoS2 composites with different mass ratios was investigated under visible light. The results show that a small amount of MoS2 combined with g-C3N4 can significantly improve photocatalytic activity. The g-C3N4/MoS2 composite with a mass ratio of 1:8 has the highest photocatalytic activity, and the degradation rate of Rh B increases from 50% to 99.6%. The main reason is that MoS2 and g-C3N4 have a matching band structure. The separation rate of photogenerated electron-hole pairs is enhanced. So the g-C3N4/MoS2 composite can improve the photocatalytic activity. The photocatalytic mechanism was proposed through the active matter capture experiment.

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Comparative Study of the Photocatalytic Hydrogen Evolution over Cd1−xMnxS and CdS-β-Mn3O4-MnOOH Photocatalysts under Visible Light

Nanomaterials ◽

10.3390/nano11020355 ◽

2021 ◽

Vol 11 (2) ◽

pp. 355

Author(s):

Ksenia O. Potapenko ◽

Anna Yu. Kurenkova ◽

Andrey V. Bukhtiyarov ◽

Evgeny Yu. Gerasimov ◽

Svetlana V. Cherepanova ◽

...

Keyword(s):

Solid Solution ◽

Visible Light ◽

Hydrogen Evolution ◽

Photoelectron Spectroscopy ◽

Diffuse Reflectance Spectroscopy ◽

Diffraction Method ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Manganese Salts

A series of solid solutions of cadmium and manganese sulfides, Cd1−xMnxS (x = 0–0.35), and composite photocatalysts, CdS-β-Mn3O4-MnOOH, were synthesized by precipitation with sodium sulfide from soluble cadmium and manganese salts with further hydrothermal treatment at 120 °C. The obtained photocatalysts were studied by the X-ray diffraction method (XRD), UV-vis diffuse reflectance spectroscopy, transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and N2 low temperature adsorption. The photocatalysts were tested in hydrogen production using a Na2S/Na2SO3 aqueous solution under visible light (λ = 450 nm). It was shown for the first time that both kinds of photocatalysts possess high activity in hydrogen evolution under visible light. The solid solution Cd0.65Mn0.35S has an enhanced photocatalytic activity due to its valence and conduction band position tuning, whereas the CdS-β-Mn3O4-MnOOH (40–60 at% Mn) samples were active due to ternary heterojunction formation. Further, the composite CdS-β-Mn3O4-MnOOH photocatalyst had much higher stability in comparison to the Cd0.65Mn0.35S solid solution. The highest activity was 600 mmol g−1 h−1, and apparent quantum efficiency of 2.9% (λ = 450 nm) was possessed by the sample of CdS-β-Mn3O4-MnOOH (40 at% Mn).

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Enhancement of Photocatalytic Activity of ZnO/SiO2by Nanosized Pt for Photocatalytic Degradation of Phenol in Wastewater

International Journal of Photoenergy ◽

10.1155/2012/103672 ◽

2012 ◽

Vol 2012 ◽

pp. 1-8 ◽

Cited By ~ 2

Author(s):

R. M. Mohamed ◽

M. A. Barakat

Keyword(s):

Photocatalytic Activity ◽

Photocatalytic Degradation ◽

Surface Area ◽

Diffuse Reflectance Spectroscopy ◽

Sol Gel ◽

Phenol Degradation ◽

Synthetic Wastewater ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron

ZnO- nanoparticles were synthesized by a sol-gel technique from and tetraethyl orthosilicate (TEOS). The synthesized samples were further modified by nanosized Pt from H2PtCl6solution through photoassisted deposition (PAD) and impregnation (Img) routes. The obtained samples were characterized by a series of techniques including X-ray diffraction (XRD), UV-Vis diffuse reflectance spectroscopy, N2adsorption, extended X-ray absorption fine structure (EXAFS), and transmission electron microscopy (TEM). The photocatalytic activity of the Pt-ZnO/ was evaluated by photocatalytic degradation of phenol in synthetic wastewater under UV-irradiation. Results obtained revealed that the surface area and the photocatalytic activity of the prepared samples were increased in the order ZnO/ < PAD: Pt-ZnO/ < img: Pt-ZnO/. The surface area decreased from 480 to 460 and 450 m2/g, while the efficiency of the phenol degradation increased from 80 to 85 and 100%, with the ZnO/, Img: Pt-ZnO-, and PAD: Pt-ZnO- samples, respectively.

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Cobalt and sulfur co-doped TiO2 nanostructures with enhanced photo-response properties for photocatalyst

Functional Materials Letters ◽

10.1142/s1793604717500618 ◽

2017 ◽

Vol 10 (05) ◽

pp. 1750061 ◽

Cited By ~ 5

Author(s):

Qiu Jin ◽

Chaoyin Nie ◽

Qianqian Shen ◽

Yusheng Xu ◽

Yanzhong Nie

Keyword(s):

Visible Light ◽

Photoelectron Spectroscopy ◽

Sol Gel ◽

Response Threshold ◽

X Ray Diffraction ◽

X Ray ◽

Valence States ◽

Transmission Electron ◽

Photo Response ◽

Co Doped

Cobalt (Co) and sulfur (S) co-doped titanium dioxide (TiO2) catalysts were synthesized via sol–gel method. The structure of TiO2was characterized by X-ray diffraction (XRD) and transmission electron microscope (TEM). The valence states of elements were studied by X-ray photoelectron spectroscopy (XPS), and the optical-absorption properties of the catalysts were tested using the ultraviolet–visible (UV–Vis) spectrophotometer. The results showed that the grain sizes of Co and S co-doped TiO2 decreased with the increase of Co and S doping concentration within a certain range, and then the catalysts had obvious red shift on the absorption of visible light. Sample (2%Co–5%S–TiO2) showed excellent light absorption characteristics and the photo-response threshold increased significantly to about 760[Formula: see text]nm. Also, the further degradation test under visible light shows the 2%Co–5%S-TiO2 sample exhibit apparently improved degradation efficiency for Rhodamine B compared to the undoped one.

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Neodymium-DopedTiO2with Anatase and Brookite Two Phases: Mechanism for Photocatalytic Activity Enhancement under Visible Light and the Role of Electron

International Journal of Photoenergy ◽

10.1155/2012/716087 ◽

2012 ◽

Vol 2012 ◽

pp. 1-10 ◽

Cited By ~ 27

Author(s):

Douga Nassoko ◽

Yan-Fang Li ◽

Jia-Lin Li ◽

Xi Li ◽

Ying Yu

Keyword(s):

Photocatalytic Activity ◽

Visible Light ◽

Photocatalytic Degradation ◽

Photoelectron Spectroscopy ◽

Diffuse Reflectance Spectroscopy ◽

Organic Pollutant ◽

Sol Gel ◽

Reactive Species ◽

X Ray ◽

Photogenerated Electrons

Titanium dioxide (TiO2) doped with neodymium (Nd), one rare earth element, has been synthesized by a sol-gel method for the photocatalytic degradation of rhodamine-B under visible light. The prepared samples are characterized by X-ray diffractometer, Raman spectroscopy, UV-Vis diffuse reflectance spectroscopy, X-ray photoelectron spectroscopy, and Brunauer-Emmett-Teller measurement. The results indicate that the prepared samples have anatase and brookite phases. Additionally, Nd as Nd3+may enter into the lattice ofTiO2and the presence of Nd3+substantially enhances the photocatalytic activity ofTiO2under visible light. In order to further explore the mechanism of photocatalytic degradation of organic pollutant, photoluminescence spectrometer and scavenger addition method have been employed. It is found that hydroxide radicals produced by Nd-dopedTiO2under visible light are one of reactive species for Rh-B degradation and photogenerated electrons are mainly responsible for the formation of the reactive species.

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Dye-Sensitized-Assisted, Enhanced Photocatalytic Activity of TiO2/Bi4V2O11

NANO ◽

10.1142/s1793292018500285 ◽

2018 ◽

Vol 13 (03) ◽

pp. 1850028 ◽

Cited By ~ 4

Author(s):

Mengjun Liang ◽

Zhiyuan Yang ◽

Ying Mei ◽

Haoran Zhou ◽

Shuijin Yang

Keyword(s):

Photocatalytic Activity ◽

Photoelectron Spectroscopy ◽

Diffuse Reflectance Spectroscopy ◽

X Ray Diffraction ◽

X Ray ◽

Dye Sensitized ◽

Transmission Electron ◽

Efficient Charge ◽

Degradation Activity ◽

Adsorption Desorption

In this study, the TiO2/Bi4V2O[Formula: see text] nanocomposite photocatalysts were prepared by loading different amount of TiO2 nanoparticles onto the surface of Bi4V2O[Formula: see text] nanospheres via a facile hydrothermal method. Afterwards, the as-synthesized samples were characterized by high-resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), N2 adsorption–desorption isotherms, X-ray photoelectron spectroscopy (XPS), UV-Vis diffuse reflectance spectroscopy (DRS) and photocurrent techniques. The optimal TiO2/Bi4V2O[Formula: see text] composite with 20[Formula: see text]wt.% TiO2 loading (TB2) exhibited the best photocatalytic activity, which could degrade almost RhB completely within 30[Formula: see text]min under visible light irradiation. The enhanced photocatalytic activity of TiO2/Bi4V2O[Formula: see text] composites for RhB degradation could be mainly ascribed to the efficient charge separation over dye-induced sensitized and the increased specific surface area. Also, the photocatalytic activities of TiO2/Bi4V2O[Formula: see text] for CIP degradation were tested. After five consecutive recycling experiments, the photocatalytic degradation activity of TB2 could still reach 99% which indicated that the catalysts had superior stability. Based on the experimental and bandgap calculations, a possible photocatalytic mechanism of TiO2/Bi4V2O[Formula: see text] for RhB degradation was proposed.

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