scholarly journals Photodegradation of Methyl Orange Using Magnetically Recoverable AgBr@Ag3PO4/Fe3O4Photocatalyst under Visible Light

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Zhen Wang ◽  
Lu Yin ◽  
Ziwen Chen ◽  
Guowang Zhou ◽  
Huixiang Shi
Keyword(s):  
Photocatalytic Activity ◽  
Methyl Orange ◽  
Visible Light ◽  
High Performance ◽  
Diffuse Reflectance Spectroscopy ◽  
X Ray Diffraction ◽  
Electron Hole ◽  
Transmission Electron ◽  
Activity Enhancement ◽  
Matching Band

A novel magnetically recoverable AgBr@Ag3PO4/Fe3O4hybrid was prepared by a simple deposition-precipitation approach and characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and UV-Vis diffuse reflectance spectroscopy (DRS). The results revealed that the photocatalytic activity and stability of AgBr@Ag3PO4/Fe3O4composite toward decomposition of methyl orange (MO) dye were superior to those of pure Ag3PO4under visible light irradiation. The photocatalytic activity enhancement of AgBr@Ag3PO4/Fe3O4is closely related to the efficient separation of electron-hole pairs derived from the matching band potentials between Ag3PO4and AgBr, as well as the good conductivity of Fe3O4. Moreover, the photocatalyst could be easily separated by applying an external magnetic field due to its magnetic property. The quenching effects of different scavengers proved that active h+and played the major role for the MO degradation. This work would provide new insight for the construction of visible light responsible photocatalysts with high performance, good stability, and recoverability.

Few-Layered MoS2 Nanostructures for Highly Efficient Visible Light Photocatalysis

NANO ◽  
2016 ◽  
Vol 11 (10) ◽  
pp. 1650114 ◽  
Author(s):  
Dan Li ◽  
Jianwei Li ◽  
Caiqin Han ◽  
Xinsheng Zhao ◽  
Haipeng Chu ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Photocatalytic Activity ◽  
Visible Light ◽  
Electrochemical Impedance ◽  
X Ray Diffraction ◽  
Electron Hole ◽  
Electrochemical Impedance Spectra ◽  
X Ray ◽  
Transmission Electron ◽  
Electron Hole Pair

Few-layered MoS2 nanostructures were successfully synthesized by a simple hydrothermal method without the addition of any catalysts or surfactants. Their morphology, structure and photocatalytic activity were characterized by X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, transmission electron microscopy, electrochemical impedance spectra and UV-Vis absorption spectroscopy, respectively. These results show that the MoS2 nanostructures synthesized at 180[Formula: see text]C exhibit an optimal visible light photocatalytic activity (99%) in the degradation of Rhodamine B owing to the relatively easier adsorption of pollutants, higher visible light absorption and lower electron–hole pair recombination.

Enhanced visible-active photocatalytic behaviors observed in Mn-doped BiFeO3

2018 ◽  
Vol 32 (17) ◽  
pp. 1850185 ◽  
Author(s):  
Yun-Hui Si ◽  
Yu Xia ◽  
Ya-Yun Li ◽  
Shao-Ke Shang ◽  
Xin-Bo Xiong ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Visible Light ◽  
Band Gap ◽  
Diffuse Reflectance Spectroscopy ◽  
X Ray Diffraction ◽  
Electron Hole ◽  
X Ray ◽  
Mn Doped ◽  
Hole Recombination ◽  
Narrow Band Gap Semiconductors

A series of BiFeO3 and BiFe[Formula: see text]Mn[Formula: see text]O3 (x = 0, 0.02, 0.04, 0.06, 0.08, 0.10) were synthesized by a hydrothermal method. The samples were characterized by X-ray diffraction, scanning electron microscopy, energy dispersive spectroscopy (EDS) and UV–Vis diffuse reflectance spectroscopy, and their photocatalytic activity was studied by photocatalytic degradation of methylene blue in aqueous solution under visible light irradiation. The band gap of BiFeO3 was significantly decreased from 2.26 eV to 1.90 eV with the doping of Mn. Furthermore, the 6% Mn-doped BiFeO3 photocatalyst exhibited the best activity with a degradation rate of 94% after irradiation for 100 min. The enhanced photocatalytic activity with Mn doping could be attributed to the enhanced optical absorption, increment of surface reactive sites and reduction of electron–hole recombination. Our results may be conducive to design more efficient photocatalysts responsive to visible light among narrow band gap semiconductors.

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

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Qianzhi Xu ◽  
Xiuying Wang ◽  
Xiaoli Dong ◽  
Chun Ma ◽  
Xiufang Zhang ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Visible Light ◽  
Photoelectron Spectroscopy ◽  
Diffuse Reflectance Spectroscopy ◽  
Sol Gel ◽  
X Ray Diffraction ◽  
Sunlight Irradiation ◽  
X Ray ◽  
Transmission Electron ◽  
Photoinduced Charge

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.

scholarly journals The Contrastive Research in the Photocatalytic Activity of BiOBr Synthesized by Different Reactants

2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
Wang Ling-Li ◽  
Ma Wan-Hong ◽  
Wang Shu-Lian ◽  
Zhang Yu ◽  
Jia Man-Ke ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Visible Light ◽  
Diffuse Reflectance Spectroscopy ◽  
Removal Rate ◽  
Active Species ◽  
X Ray Diffraction ◽  
Toc Removal ◽  
Transmission Electron ◽  
Uv Visible ◽  
Adsorption Desorption

BiOBr nanoplates, marked asα-BiOBr andβ-BiOBr, were synthesized via hydrothermal method using cetylpyridinium bromide (CPB) and NaBr as reactants, respectively. X-Ray Diffraction (XRD), transmission electron microscope (TEM), N2adsorption/desorption, UV-visible diffuse reflectance spectroscopy (UV-Vis DRS), and cyclic voltammetry (CV) were employed to characterize the obtained BiOBr. The results showed thatα-BiOBr andβ-BiOBr can absorb visible light and both the band gaps of them were about 2.76 eV. Under visible light irradiation, the photodegradation of organic dye sulforhodamine (SRB) and salicylic acid (SA) usingα-BiOBr andβ-BiOBr as the catalysts was carried out. The reaction kinetic constants of the degradation of SRB byα-BiOBr andβ-BiOBr were 0.00602 min−1and 0.0047 min−1, respectively, which indicated that the photocatalytic activity ofα-BiOBr was higher than that ofβ-BiOBr. The UV-Vis DRS and total organic carbon (TOC) were also monitored, and the TOC removal rate ofα-BiOBr andβ-BiOBr was 86% and 48%, respectively. At the same time, hydrogen peroxide (H2O2) and active radicals were measured and analyzed, which showed that the main active species wasOH∙during the photocatalytic reaction.

FABRICATION OF SQUARAINE DYE SENSITIZED SPHERICAL ZINC OXIDE NANOCOMPOSITES AND THEIR VISIBLE-LIGHT INDUCED PHOTOCATALYTIC ACTIVITY

NANO ◽  
2014 ◽  
Vol 09 (03) ◽  
pp. 1450036 ◽  
Author(s):  
YONGLING FANG ◽  
ZHONGYU LI ◽  
SONG XU ◽  
DANAN HAN ◽  
DAYONG LU
Keyword(s):  
Photocatalytic Activity ◽  
Visible Light ◽  
Degradation Rate ◽  
Diffuse Reflectance Spectroscopy ◽  
Light Illumination ◽  
X Ray Diffraction ◽  
Preparation Methods ◽  
Dye Sensitized ◽  
Transmission Electron ◽  
Xrd Patterns

A 1,3-bis[(3,3-dimethylindolin-2-ylidene)methyl]squaraine (ISQ) dye sensitized ZnO nanocomposites via two different preparation methods including hydrothermal and ultrasonic sensitization processes are discussed in this paper. The as-prepared composites were characterized by the X-ray diffraction (XRD), UV-Vis diffuse reflectance spectroscopy (DRS), Raman spectroscopy, and transmission electron microscopy (TEM). Based on the XRD patterns and TEM images, the ISQ/ ZnO nanocomposites still kept the characteristic peaks and the basic morphology of ZnO and ISQ dye. The photocatalytic activity of ISQ/ ZnO nanocomposites was investigated by degrading methylene blue (MB) under visible-light illumination. Compared with the MB self-degradation rate, the photocatalytic activity of the ISQ/ ZnO composites was enhanced remarkably. The ISQ/ ZnO nanocomposites fabricated by ultrasonic sensitization method exhibited excellent photocatalytic degradation rate, approximately 20% higher than that of the hydrothermal sensitization one.

Enhancement in Photocatalytic Activity of Nano-TiO2 Photocatalyst by Carbon Doping

2013 ◽  
Vol 757 ◽  
pp. 271-284 ◽  
Author(s):  
Amrit Pal Toor ◽  
Neha Yadav ◽  
R.K. Wanchoo
Keyword(s):  
Photocatalytic Activity ◽  
Visible Light ◽  
Diffuse Reflectance Spectroscopy ◽  
Kinetic Studies ◽  
Carbon Doping ◽  
X Ray Diffraction ◽  
Pseudo First Order Reaction ◽  
Carbon Doped ◽  
Transmission Electron ◽  
Light Region

The carbon doped TiO2 nanoparticles with different amount of carbon content were prepared using starch as the carbon source. The physical properties of the as-prepared catalyst were determined using X-ray diffraction, transmission electron microscopy and UV-vis diffuse reflectance spectroscopy. The results showed that carbon was successfully doped into TiO2 and the optical response of TiO2 was shifted from UV to the visible light region. The photocatalytic activity of these catalysts was evaluated by the degradation of phenol under UV and visible light irradiation. C-doped TiO2 nanocomposites showed better photocatalytic activity than the undoped TiO2 nanoparticles. The degradation rate of phenol on C-doped TiO2 was higher than those of pure TiO2 under visible light. As the results, C-doped TiO2 possessed better absorption ability of visible light. The kinetic studies revealed that the degradation of phenol follows pseudo first order reaction relationship.

scholarly journals Synthesis of CdIn2S4Microsphere and Its Photocatalytic Activity for Azo Dye Degradation

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Jianhui Huang ◽  
Wei Lin ◽  
Jianqin Chen
Keyword(s):  
Electron Microscopy ◽  
Photocatalytic Activity ◽  
Methyl Orange ◽  
Diffuse Reflectance Spectroscopy ◽  
Dye Degradation ◽  
Ultrasonic Spray Pyrolysis ◽  
Mesoporous Structure ◽  
X Ray Diffraction ◽  
Ultrasonic Spray ◽  
Transmission Electron

CdIn2S4was prepared by ultrasonic spray pyrolysis. The prepared CdIn2S4was characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FSEM), transmission electron microscopy (TEM), UV-visible diffuse reflectance spectroscopy (UV-Vis DRS), and N2-sorption techniques. Aqueous photocatalytic activity was evaluated by the decomposition of methyl orange under visible light irradiation. The results indicate that the prepared CdIn2S4has spherical morphology with mesoporous structure which can efficiently degrade methyl orange in water. The sample prepared at 500°C exhibits the optimized photocatalytic activity.

scholarly journals Facile Synthesis of Uniform Mesoporous Nb2O5 Micro-Flowers for Enhancing Photodegradation of Methyl Orange

Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 3783
Author(s):  
Jian-Qing Qiu ◽  
Huan-Qing Xie ◽  
Ya-Hao Wang ◽  
Lan Yu ◽  
Fang-Yuan Wang ◽  
...  
Keyword(s):  
Methyl Orange ◽  
Active Sites ◽  
High Performance ◽  
Diffuse Reflectance Spectroscopy ◽  
X Ray Diffraction ◽  
Flower Structure ◽  
Electron Microscopies ◽  
Bet Method ◽  
One Step ◽  
Catalytic Active Sites

The removal of organic pollutants using green environmental photocatalytic degradation techniques urgently need high-performance catalysts. In this work, a facile one-step hydrothermal technique has been successfully applied to synthesize a Nb2O5 photocatalyst with uniform micro-flower structure for the degradation of methyl orange (MO) under UV irradiation. These nanocatalysts are characterized by transmission and scanning electron microscopies (TEM and SEM), X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET) method, and UV-Vis diffuse reflectance spectroscopy (DRS). It is found that the prepared Nb2O5 micro-flowers presents a good crystal phases and consist of 3D hierarchical nanosheets with 400–500 nm in diameter. The surface area is as large as 48.6 m2 g−1. Importantly, the Nb2O5 micro-flowers exhibit superior catalytic activity up to 99.9% for the photodegradation of MO within 20 mins, which is about 60-fold and 4-fold larger than that of without catalysts (W/O) and commercial TiO2 (P25) sample, respectively. This excellent performance may be attributed to 3D porous structure with abundant catalytic active sites.

PEG-Assisted Hydrothermal Synthesis and Photocatalytic Activity of Bi2Fe4O9 Crystallites

2011 ◽  
Vol 1292 ◽  
Author(s):  
Dengrong Cai ◽  
Jianmin Li ◽  
Shundong Bu ◽  
Shengwen Yu ◽  
Dengren Jin ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Visible Light ◽  
Diffuse Reflectance Spectrum ◽  
X Ray Diffraction ◽  
Hydrothermal Route ◽  
Peg 400 ◽  
Transmission Electron ◽  
Light Region ◽  
Facile Hydrothermal Route ◽  
Degradation Ratio

ABSTRACTA facile hydrothermal route assisted by polyethylene glycol (PEG) 400 was utilized to synthesize single-phase Bi2Fe4O9 crystallites. X-ray diffraction results showed the products with PEG 400 of 30 g/L exhibited a preferred growth along the (001) plane. Transmission electron microscopy indicated that the morphology of the as-prepared Bi2Fe4O9 crystallites with PEG 400 were plake-like and rod-like. Strong absorption in visible-light region of the products was characterized by UV-vis diffuse reflectance spectrum (UV-DRS). The photocatalytic activity of Bi2Fe4O9 crystallites was evaluated on degradation of methyl orange (MO) under visible light irradiation. For 3 h irradiation, the degradation ratio was increased to 93% with the aid of a small amount of H2O2. The analysis of FT-IR spectra proved that the Bi2Fe4O9 catalysts were remained stable after the photocalytic reactions.

Immobilization of BiOBr/BiOI Hierarchical Microspheres on Fly Ash Cenospheres as Visible Light Photocatalysts

2016 ◽  
Vol 69 (1) ◽  
pp. 119 ◽  
Author(s):  
Li Lin ◽  
Ya Wang ◽  
Manhong Huang ◽  
Donghui Chen
Keyword(s):  
Photocatalytic Activity ◽  
Fly Ash ◽  
Visible Light ◽  
Diffuse Reflectance Spectroscopy ◽  
Three Dimensional ◽  
One Pot ◽  
Transmission Electron ◽  
Hierarchical Microspheres ◽  
2D Nanosheets ◽  
Fly Ash Cenospheres

Three-dimensional (3D) BiOBr/BiOI hierarchical microspheres were successfully fabricated on the surface of fly ash cenospheres (FACs) via a facile one-pot solvothermal method for the first time. The as-prepared samples were characterized by XRD, SEM, energy-dispersive X-ray spectroscopy, UV–visible diffuse reflectance spectroscopy, and high-resolution transmission electron microscopy. The results indicated that the loaded hierarchical microspheres exhibited a uniform distribution, and some aggregation was observed. These well-dispersed hierarchical microspheres were composed of 2D nanosheets, which possess heterojunction structures. Based on the photodegradation tests examining the removal of rhodamine B from water under visible light irradiation (λ > 420 nm), the photocatalytic activity of BiOB/BiOI/FACs was superior to that of BiOBr/FACs and BiOI/FACs. A proposed mechanism for the enhanced photocatalytic activity displayed by BiOB/BiOI/FACs is discussed.

Sign in / Sign up

Export Citation Format

Share Document