scholarly journals CoFe2O4−Fe3O4Magnetic Nanocomposites as Photocatalyst for the Degradation of Methyl Orange Dye

2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
Debabrata Mishra ◽  
Kula Kamal Senapati ◽  
Chandan Borgohain ◽  
A. Perumal
Keyword(s):  
Photocatalytic Activity ◽  
Methyl Orange ◽  
Organic Contaminants ◽  
Magnetic Hysteresis ◽  
Hydrothermal Process ◽  
Textile Wastewater ◽  
Band Gap Energy ◽  
Blocking Temperature ◽  
Magnetic Phase Transitions ◽  
Temperature Dependent

We report the investigation of temperature-dependent magnetic properties and photocatalytic activity ofCoFe2O4−Fe3O4magnetic nanocomposites (MNCs) synthesized by hydrothermal process. Room-temperature magnetic hysteresis (M-H) loops result enhanced saturation magnetization of 90 emu/g and coercivity (HC) of 530 Oe forCoFe2O4−Fe3O4MNCs. With decreasing temperature to 20 K,HCincreases from 500 Oe to 6800 Oe, and the M-H loops exhibit exchange coupling feature betweenCoFe2O4andFe3O4. Low- and high-temperature-dependent magnetization measurements confirm that the blocking temperature lies above 300 K and the presence of two magnetic phase transitions corresponding toCoFe2O4andFe3O4, respectively. The photocatalytic activity of the MNCs has been examined on the reduction of methyl orange (MO), a colored compound used in dyeing and printing textiles. The observed results suggest that theCoFe2O4−Fe3O4MNCs act as an excellent photocatalyst on the degradation of organic contaminants and degrade 93% of MO in 5 hours of UV irradiation. The photocatalytic activity of MNCs is attributed to remarkably high band gap energy and small particle size. Also, the MNCs with a reproducible photocatalytic activity are well separable from water media by applying external magnetic field and acts as a promising catalyst for the remediation of textile wastewater.

scholarly journals Synthesis and Characterization of Ag@C-TiO2 Nanocomposite for Degradation of Sasirangan Textile Wastewater

2019 ◽  
Vol 22 (6) ◽  
pp. 299-304
Author(s):  
Heny Puspita Dewi ◽  
Joko Santoso ◽  
Nur Firda Trianda ◽  
Rodiansono Rodiansono
Keyword(s):  
Methylene Blue ◽  
Photocatalytic Activity ◽  
Photocatalytic Degradation ◽  
Textile Wastewater ◽  
Band Gap Energy ◽  
Tio2 Photocatalyst ◽  
Composite Photocatalysts ◽  
Xrd Patterns ◽  
Brookite Phase

Carbon-titanium oxide nanocomposite (denoted as @C-TiO2) was successfully synthesized via hydrothermal method at 150°C for 24 h. The C-TiO2 nanocomposite was furtherly modified by adding an Ag metal dopant (denoted as Ag@C-TiO2) to improve and applied to the photocatalytic degradation of Sasirangan textile wastewater. The composite photocatalysts were characterized by XRD and UV–Vis DRS spectroscopies. XRD patterns showed that TiO2 in @C-TiO2 mainly consisted of a brookite phase, as indicated by a series sharp diffraction peak at 2θ = 27.2° (111), 31.5° (121) and 55.9° (241). The calculated band gap energy (Eg) derived from UV-Vis DRS spectra for TiO2, @C-TiO2, and Ag@C-TiO2 were 2.95 eV, 2.54 eV, and 2.74 eV, respectively. Ag@C-TiO2 photocatalyst was found to be active for the photocatalytic degradation of Sasirangan textile wastewater, as indicated by the change of wastewater color from dark to clear. The quantitative photocatalytic activity of Ag@C-TiO2 was evaluated in the degradation of methylene blue, whereas the conversion of methylene blue was 41.3%. The addition of Ag to @C-TiO2 is believed to play an essential role in the enhancement of photocatalytic activity.

Highly Active S-Doping MnFe2O4 by Synthesis and Photo-Fenton Catalytic Property Research

2014 ◽  
Vol 1073-1076 ◽  
pp. 795-798
Author(s):  
Yu Niu ◽  
Fu Ying Li ◽  
Ren Zhang Wang
Keyword(s):  
Photocatalytic Activity ◽  
Methyl Orange ◽  
Visible Light Irradiation ◽  
Hydrothermal Process ◽  
Reflectance Spectroscopy ◽  
Basic Fuchsin ◽  
X Ray ◽  
Ph Values ◽  
Highly Active ◽  
Degradation Ratio

Composite oxide MnFe2O4 have been synthesized via the hydrothermal process and then modified by S=O. These compounds were characterized by X-ray diffusions, and ultraviolet-visible diffusion reflectance spectroscopy. MnFe2O4 exhibits stronger photocatalytic activity, with 95.5% degradation ratio of methyl orange and 91% degradation ratio of basic fuchsin, after 120 minutes visible-light irradiation in the presence of H2O2. In addition, the effect of pH values on photocatalytic activity were also investigated.

scholarly journals Synthesis and enhanced photocatalytic performance of 0D/2D CuO/tourmaline composite photocatalysts

2020 ◽  
Vol 11 ◽  
pp. 407-416 ◽  
Author(s):  
Changqiang Yu ◽  
Min Wen ◽  
Zhen Tong ◽  
Shuhua Li ◽  
Yanhong Yin ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Organic Contaminants ◽  
Hydrothermal Process ◽  
Charge Carriers ◽  
Molecular Vibration ◽  
Surface Element ◽  
Composite Photocatalysts ◽  
Excellent Photocatalytic Activity ◽  
Photoinduced Charge ◽  
Facile Hydrothermal Process

Photocatalysis is considered to be a green and promising technology for transforming organic contaminants into nontoxic products. In this work, a CuO/tourmaline composite with zero-dimensional/two-dimensional (0D/2D) CuO architecture was successfully obtained via a facile hydrothermal process, and its photocatalytic activity was evaluated by the degradation of methylene blue (MB). Surface element valence state and molecular vibration characterization revealed that CuO chemically interacted with tourmaline via Si–O–Cu bonds. The specific surface area of the CuO/tourmaline composite (23.60 m2 g−1) was larger than that of the pristine CuO sample (3.41 m2 g−1). The CuO/tourmaline composite exhibited excellent photocatalytic activity for the degradation of MB, which was ascribed to the increase in the quantity of the adsorption-photoreactive sites and the efficient utilization of the photoinduced charge carriers. This study provides a facile strategy for the construction of 0D/2D CuO structures and the design of tourmaline-based functional composite photocatalysts for the treatment of organic contaminants in water.

Effect of pretreatment temperature on the photocatalytic activity of microwave irradiated porous nanocrystalline ZnO

2015 ◽  
Vol 39 (1) ◽  
pp. 321-332 ◽  
Author(s):  
Tarek T. Ali ◽  
Katabathini Narasimharao ◽  
Ivan P. Parkin ◽  
Claire J. Carmalt ◽  
Sanjayan Sathasivam ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Methyl Orange ◽  
Photocatalytic Degradation ◽  
Crystallite Size ◽  
Band Gap Energy ◽  
Gap Energy ◽  
Pretreatment Temperature ◽  
Short Time ◽  
High Band ◽  
Degradation Of Methyl Orange

ZnO treated at 200 °C offered high photocatalytic degradation of methyl orange (99%) in a short time (90 min). The activity can be attributed to several factors including low crystallite size, high band gap energy and porosity.

An Inexpensive, Stable and Highly Efficient Photocatalyst for Degradation of Organic Dyes in Water: Core-Shell Montmorillonite-TiO2 Colloids

2013 ◽  
Vol 864-867 ◽  
pp. 404-407
Author(s):  
Shi Zhao Kang ◽  
Tan Wu ◽  
Xiang Qing Li ◽  
Yi Lun Zhou ◽  
Jin Mu
Keyword(s):  
Photocatalytic Activity ◽  
Methyl Orange ◽  
Organic Dyes ◽  
Hydrothermal Process ◽  
Core Shell ◽  
X Ray Diffraction ◽  
X Ray ◽  
Highly Efficient ◽  
Transmission Electron ◽  
The Stability

Core-shell montmorillonite-TiO2 colloids were prepared in a hydrothermal process and characterized with transmission electron microscope, powder X-ray diffraction analysis, Brunauer-Emmett-Teller analysis and UV-vis spectra. Afterwards, their photocatalytic activity was investigated under UV irradiation using methyl orange as a model contaminant. In addition, the stability of the core-shell montmorillonite-TiO2 colloids was investigated by repeatedly performing methyl orange photocatalytic degradation experiments. The results indicate the as-prepared core-shell montmorillonite-TiO2 colloids are a highly efficient photocatalyst for the degradation of organic dyes in water. And this photocatalytic activity remains almost unchanged after eight successive cycles.

Facile Preparation of the Single Crystalline In2S3 Nanosheets with Highly Efficient Photocatalytic Activity

2013 ◽  
Vol 834-836 ◽  
pp. 8-11
Author(s):  
Hao Yong Yin ◽  
Jun Hong Tang ◽  
Chun Jie Yan ◽  
Qiu Lin Nie ◽  
Dan Wu ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Methyl Orange ◽  
Organic Pollutants ◽  
Hydrothermal Process ◽  
Photocatalytic Decomposition ◽  
Single Crystalline ◽  
Highly Efficient ◽  
Sem And Tem ◽  
Facile Preparation ◽  
Facile Hydrothermal Process

The single crystalline In2S3 nanosheets with highly efficient photocatalytic activity have been controllably synthesized via a facile hydrothermal process without adding any surfactant. The morphologies of the nanosheets were characterized by SEM and TEM. The results show the diameter of the nanosheets ranges from 100nm to 400nm. The photocatalytic decomposition of methyl orange on the catalyst shows it has much higher photoactivity than that of nanoTiO2 which means it may be more capable to be used as photocatalyst in decomposition of organic pollutants.

A Novel Magnetically Separable Photocatalyst Silver Vanadate@ SiO2/Fe3O4

2011 ◽  
Vol 356-360 ◽  
pp. 455-458
Author(s):  
Long Hui Nie ◽  
Ya Peng Meng ◽  
Bo Rui Yang ◽  
Zheng Qiang Xiao ◽  
Lei Fang ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Methyl Orange ◽  
Visible Light ◽  
Hydrothermal Process ◽  
High Photocatalytic Activity ◽  
Main Phase ◽  
Prepared Sample ◽  
Silver Vanadate ◽  
Magnetically Separable ◽  
Degradation Of Methyl Orange

A magnetically separable photocatalyst silver vanadates@SiO2/Fe3O4was prepared by hydrothermal process. The prepared sample was composed of mixed phases of a–Ag3VO4and Ag4V2O4, and the main phase was a–Ag3VO4. The bandgap of the synthesized sample was 2.2 eV. In the degradation of methyl orange (MO) solution under the visible light (l>420 nm), the silver vanadates@SiO2/Fe3O4showed high photocatalytic activity in two-cycle photocatalytic test.

scholarly journals Novel Ternary Heterogeneous Reduction Graphene Oxide (RGO)/BiOCl/TiO2 Nanocomposites for Enhanced Adsorption and Visible-Light Induced Photocatalytic Activity toward Organic Contaminants

Materials ◽  
2020 ◽  
Vol 13 (11) ◽  
pp. 2529 ◽  
Author(s):  
Zhanxin Jing ◽  
Xiangyi Dai ◽  
Xueying Xian ◽  
Qiongshan Zhang ◽  
Huojiao Zhong ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Photoelectron Spectroscopy ◽  
Organic Contaminants ◽  
Photocatalytic Performance ◽  
Diffuse Reflectance Spectroscopy ◽  
Hydrothermal Process ◽  
Reaction System ◽  
Cost Effective ◽  
Active Species ◽  
X Ray

Herein, we describe a simple and cost-effective design for the fabrication of a novel ternary RGO/BiOCl/TiO2 nanocomposites through a simple hydrothermal process. The prepared nanocomposites were characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), X-ray diffraction (XRD), UV–vis diffuse reflectance spectroscopy (UV–vis DRS) and N2 adsorption–desorption analysis. Organic contaminants—such as methylene blue (MB), methyl orange (MO), rhodamine B (RhB) and amido black-10B (AB-10B)—were employed as the target pollutants to evaluate the adsorption capacity and photocatalytic activity of RGO/BiOCl/TiO2 nanocomposites. From experimental data, it was also found that the amount of TiO2 impressed the photocatalytic performance, and the nanocomposites with 10% of TiO2 showed the best photocatalytic activity. The improved photocatalytic performance may be mainly due to the narrow band gap, and the charge separation and migration of RGO. Moreover, good recyclability was obtained from RGO/BiOCl/TiO2 nanocomposites, and scavenger tests indicated that photogenerated holes were the main active species in the reaction system. Therefore, the prepared RGO/BiOCl/TiO2 nanocomposites have broad applications foreground in pollutants purification.

Ultrasonic-Assisted Synthesis and Photocatalytic Activity of TiO2 Nanoparticles for Methyl Orange Degradation under Visible Light

2018 ◽  
Author(s):  
Edgar Mosquera ◽  
Daniela Herrera ◽  
Marcela Quintero ◽  
Ramesh Sivasamy ◽  
Andreina García ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Methyl Orange ◽  
Visible Light ◽  
Tio2 Nanoparticles ◽  
Sol Gel ◽  
Band Gap Energy ◽  
Degradation Reactions ◽  
Transmission Electron ◽  
Vis Spectroscopy ◽  
Ultrasonic Assisted

TiO2 nanoparticles were successfully synthesized using a facile and scalable sol-gel method followed by calcination in air. The structural and optical properties, along with the photocatalytic performance of the nanoparticles were analyzed using X-ray diffraction, infrared spectroscopy, transmission electron microscopy, energy dispersive spectroscopy, UV-vis spectroscopy, photoluminescence spectroscopy, and degradation of anionic azo dye (methyl orange (MO)) under visible light irradiation. The prepared TiO2 nanoparticles crystallize in the anatase structure with a highly crystalline order. The results showed a band gap energy of 3.59, 3.79 and 3.54 eV, respectively, which suggests a better photocatalytic activity for sample calcined at 450 °C compared to other samples’ thermal treatments. The synthesis route employed for the preparation of the TiO2 nano-photocatalyst resulted to be efficient for degradation reactions MO of dyes.

Enhanced Removal of Methyl Violet Dye from Aqueous Solution by a Novel Co3O4@SiO2@TiO2-Ag Heterogeneous Semiconductor

2021 ◽  
Vol 24 ◽  
Author(s):  
Mohammad Ali Ghasemzadeh ◽  
Zahar Elyasi ◽  
Mohammad Reza Zand Monfared
Keyword(s):  
Aqueous Solution ◽  
Photocatalytic Activity ◽  
Organic Contaminants ◽  
Irradiation Time ◽  
Low Cost ◽  
Sol Gel ◽  
Aqueous Media ◽  
Methyl Violet ◽  
Research Area ◽  
Band Gap Energy

Background : This research introduces the application of a novel photocatalyst including Co3O4@SiO2@TiO2-Ag nanocomposite with highly photocatalytic stability and core-shell structure for the removal of toxic methyl violet from aqueous solution. Objective: The removal of toxic dyes and organic contaminants from water is outstanding research area between scientists. Methyl violet as a toxic cationic pollutant has disruptive influence for humans. In this research, with a aim to remove to methyl violet from the wastewater we developed a new photocatalyst including Co3O4@SiO2@TiO2-Ag nanocomposite as a eco-friendly and low-cost nanostructure with high photocatalytic activity in order to reduce the risks of this pollutant from aqueous media. Methods: The Co3O4@SiO2@TiO2-Ag nanostructure was prepared via hydrothermal and sol-gel methods and the structure elucidation of the prepared photocatalyst was analyzed by different spectroscopy techniques including XRD, FT-IR, FE-SEM, TEM, VSM and EDX. Results: Photodegradation of methyl violet in the presence of different structures showed that Co3O4@SiO2@TiO2-Ag is superior photocatalytic activity (about 98% was decomposed after 40 min) compared to the previous shells and pure Co3O4 NPs. Loadings of SiO2@TiO2-Ag nanocomposite over the Co3O4 surface led to the reduction in the band gap energy of visible light and improvement in the photocatalytic activity of Methyl Violet dye for the aqueous phase decomposition. Conclusion: The remarkable benefits of this nanocomposite are highly photocatalytic efficiency in the degradation of methyl violet (almost 100 % within 1 h), easy magnetic separation, low cost, and high chemical stability. The collected results demonstrated the rate of degradation is increased by increasing the irradiation time, while the rate of degradation is decreased by dye concentration.

Sign in / Sign up

Export Citation Format

Share Document