Environmental remediation and synthesis of a new pigment by irradiation-induced adsorption of methylene blue onto undoped tetragonal zirconia

Earth–abundant transition metal chalcogenide materials are of great research interest for energy production and environmental remediation, as they exhibit better photocatalytic activity due to their suitable electronic and optical properties. This study focuses on the photocatalytic activity of flower-like SnS2 nanoparticles (composed of nanosheet subunits) embedded in TiO2 synthesized by a facile hydrothermal method. The materials were characterized using different techniques, and their photocatalytic activity was assessed for hydrogen evolution reaction and the degradation of methylene blue. Among the catalysts studied, 10 wt. % of SnS2 loaded TiO2 nanocomposite shows an optimum hydrogen evolution rate of 195.55 µmolg−1, whereas 15 wt. % loading of SnS2 on TiO2 exhibits better performance against the degradation of methylene blue (MB) with the rate constant of 4.415 × 10−4 s−1 under solar simulated irradiation. The improved performance of these materials can be attributed to the effective photo-induced charge transfer and reduced recombination, which make these nanocomposite materials promising candidates for the development of high-performance next-generation photocatalyst materials. Further, scavenging experiments were carried out to confirm the reactive oxygen species (ROS) involved in the photocatalytic degradation. It can be observed that there was a 78% reduction in the rate of degradation when IPA was used as the scavenger, whereas around 95% reduction was attained while N2 was used as the scavenger. Notably, very low degradation (<5%) was attained when the dye alone was directly under solar irradiation. These results further validate that the •OH radical and the superoxide radicals can be acknowledged for the degradation mechanism of MB, and the enhancement of degradation efficiency may be due to the combined effect of in situ dye sensitization during the catalysis and the impregnation of low bandgap materials on TiO2.

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Magnetically separable reduced graphene oxide/iron oxide nanocomposite materials for environmental remediation

Catalysis Science & Technology ◽

10.1039/c4cy00806e ◽

2014 ◽

Vol 4 (12) ◽

pp. 4396-4405 ◽

Cited By ~ 85

Author(s):

Teo Peik-See ◽

Alagarsamy Pandikumar ◽

Lim Hong Ngee ◽

Huang Nay Ming ◽

Chia Chin Hua

Keyword(s):

Methylene Blue ◽

Graphene Oxide ◽

Iron Oxide ◽

Photocatalytic Degradation ◽

Reduced Graphene Oxide ◽

Environmental Remediation ◽

Nanocomposite Materials ◽

Reduced Graphene ◽

Magnetically Separable

Synthesis of magnetically separable rGO/Fe3O4nanocomposite materials for environmental remediationviathe photocatalytic degradation of methylene blue.

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Low-temperature stabilization of electrosynthesized tetragonal zirconia, its photoactivity toward methylene blue decolorization

Desalination and Water Treatment ◽

10.1080/19443994.2014.960456 ◽

2014 ◽

Vol 56 (9) ◽

pp. 2402-2416 ◽

Cited By ~ 6

Author(s):

A.A. Jalil ◽

S. Triwahyono ◽

N. Sapawe ◽

I.H. Ahmed ◽

M.A.A. Aziz

Keyword(s):

Methylene Blue ◽

Low Temperature ◽

Tetragonal Zirconia ◽

Temperature Stabilization

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Lignin Biopolymer for the Synthesis of Iron Nanoparticles and the Composite Applied for the Removal of Methylene Blue

Polymers ◽

10.3390/polym13213847 ◽

2021 ◽

Vol 13 (21) ◽

pp. 3847

Author(s):

Fang-Yi Peng ◽

Pei-Wen Wang ◽

Weisheng Liao ◽

Ing-Song Yu

Keyword(s):

Methylene Blue ◽

Aqueous Solutions ◽

Environmental Remediation ◽

Present Method ◽

Room Temperature ◽

Iron Nanoparticles ◽

Reduction Method ◽

Environmental Pollutants ◽

Borohydride Reduction ◽

Natural Polymer

In the current study, lignin, an abundant natural polymer, was dissolved in ethylene glycol and acidic H2O to form nanoscale lignin. Then, zero-valent iron (ZVI) nanoparticles were synthesized in nanoscale lignin, producing a nZVI/n-lignin composite, via the borohydride reduction method. The use of nZVI/n-lignin for environmental remediation was tested by the removal of methylene blue in aqueous solutions at room temperature. The nZVI/n-lignin composite achieved a higher methylene blue removal ratio than that achieved by traditional nZVIs. Moreover, its excellent dispersibility in water and stability against oxidation in the air were observed. The functions of the nanoscale lignin in the composite material are (1) prevention of further growth and aggregation of the nZVI nanoparticles, (2) protection of nZVI from serious oxidation by H2O/O2, and (3) allowing better dispersibility of nZVI in aqueous solutions. These three functions are important for the field applications of nZVI/n-lignin, namely, to travel long distances before making contact with environmental pollutants. The present method for producing nZVI/n-lignin is straightforward, and the combination of nZVI and lignin is an efficient and environmentally friendly material for environmental applications.

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Hydrogenated Amorphous TiO2−x and Its High Visible Light Photoactivity

Nanomaterials ◽

10.3390/nano11112801 ◽

2021 ◽

Vol 11 (11) ◽

pp. 2801

Author(s):

Guang Feng ◽

Mengyun Hu ◽

Shuai Yuan ◽

Junyi Nan ◽

Heping Zeng

Keyword(s):

Methylene Blue ◽

Visible Light ◽

Rhodamine B ◽

Environmental Remediation ◽

Density Functional ◽

Electronic Band Structure ◽

Ros Generation ◽

Electronic Band ◽

Amorphous Tio2 ◽

Hydrogenated Amorphous

Hydrogenated crystalline TiO2 with oxygen vacancy (OV) defect has been broadly investigated in recent years. Different from crystalline TiO2, hydrogenated amorphous TiO2−x for advanced photocatalytic applications is scarcely reported. In this work, we prepared hydrogenated amorphous TiO2−x (HA-TiO2−x) using a unique liquid plasma hydrogenation strategy, and demonstrated its highly visible-light photoactivity. Density functional theory combined with comprehensive analyses was to gain fundamental understanding of the correlation among the OV concentration, electronic band structure, photon capturing, reactive oxygen species (ROS) generation, and photocatalytic activity. One important finding was that the narrower the bandgap HA-TiO2−x possessed, the higher photocatalytic efficiency it exhibited. Given the narrow bandgap and extraordinary visible-light absorption, HA-TiO2−x showed excellent visible-light photodegradation in rhodamine B (98.7%), methylene blue (99.85%), and theophylline (99.87) within two hours, as well as long-term stability. The total organic carbon (TOC) removal rates of rhodamine B, methylene blue, and theophylline were measured to 55%, 61.8%, and 50.7%, respectively, which indicated that HA-TiO2−x exhibited high wastewater purification performance. This study provided a direct and effective hydrogenation method to produce reduced amorphous TiO2−x which has great potential in practical environmental remediation.

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PREPARATION OF TEMPO-CELLULOSE NANOFIBER/ZINC OXIDE AS ANTIMICROBIAL AND METHYLENE BLUE PHOTO-DEGRADING NANOCOMPOSITE

Cellulose Chemistry and Technology ◽

10.35812/cellulosechemtechnol.2021.55.35 ◽

2021 ◽

Vol 55 (3-4) ◽

pp. 365-373

Author(s):

MOHAMED EL-SAKHAWY ◽

AHMED SALAMA ◽

AHMED K. EL-ZIATY ◽

HAZEM HASSAN

Keyword(s):

Methylene Blue ◽

Zinc Oxide ◽

Visible Light ◽

Visible Light Irradiation ◽

Environmental Remediation ◽

Organic Dyes ◽

Cellulose Nanofibers ◽

Light Irradiation ◽

Order Kinetic ◽

Catalytic Material

"Photo-catalytic degradation of organic dyes in aquatic environments under visible light irradiation affords an efficient and economic technique for environmental remediation. TEMPO-oxidized cellulose nanofibers/zinc oxide nanocomposite (TEMPO-CNF/ZnO) was prepared through oxidation of cellulose pulp, followed by zinc oxide precipitation in the presence of oxidized fibers. TEMPO-CNF/ZnO was characterized by different techniques. The degradation rate of methylene blue (MB) by TEMPO-CNF/ZnO was gradually increased with increasing pH and the degradation reached 86% within 340 minutes at pH 7. The kinetic study showed that the pseudo-first-order kinetic best fitted the photo-catalytic process. A mechanism was proposed for the degradation of MB using TEMPO-CNF/ZnO under visible light irradiation. TEMPO-CNF/ZnO showed high antibacterial activity against S. aureus and E. coli. Thus, the TEMPO-CNF/ZnO nanocomposite has been demonstrated to be an effective photo-catalytic material for degrading MB under visible light irradiation."

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CuFe2O4@CuO: A Magnetic Composite Synthesized by Ultrasound Irradiation and Degradation of Methylene Blue on Its Surface in the Presence of Sunlight

Proceedings ◽

10.3390/ecws-4-06438 ◽

2019 ◽

Vol 48 (1) ◽

pp. 17 ◽

Cited By ~ 1

Author(s):

Ahmad Massoud-Sharifi ◽

Gheffar K. Kara ◽

Mahboubeh Rabbani

Keyword(s):

Methylene Blue ◽

Environmental Remediation ◽

Spinel Ferrite ◽

Sol Gel ◽

Chemical Properties ◽

Pollutant Removal ◽

Magnetic Composite ◽

Hydrothermal Route ◽

X Ray ◽

Practical Applications

Spinel ferrite MFe2O4 (M = Cu, Ca, Mg, Ni, etc.) nanoparticles and their composites are a new promising materialbecause they have shown great interest in the field of sensing, optoelectronics, catalysis, and solar cells due to their unique physical and chemical properties that differ from their bulk structures. Today, lots of CuFe2O4 nanomaterials have been synthesized by different methods, such as hydrothermal route and sol-gel combustion methods. Nevertheless, there are hardly any results about photocatalytic activity. For this reason, we tried to increase optical properties by preparing a composite of CuFe2O4 nanomaterials with other oxides. In this paper, a CuFe2O4@CuO magnetic composite was synthesized via an ultrasound method. The samples prepared were characterized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), diffuse reflectance spectrpscopy (DRS), field emission scanning electron microscopy (FESEM) images, vibrating sample magnetometer (VSM), and elemental analysis (energy-dispersive X-ray (EDX)). The catalytic activity of as-synthesized CuFe2O4@CuO was evaluated using the degradation of methylene blue. Furthermore, a possible reaction mechanism was discussed. Finally, the catalyst was used for effective degradation of methylene blue (MB) in its solution, which indicated a potential for practical applications in water pollutant removal and environmental remediation.

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Titania-based heterogeneous photocatalysis. Materials, mechanistic issues, and implications for environmental remediation

Pure and Applied Chemistry ◽

10.1351/pac200173121849 ◽

2001 ◽

Vol 73 (12) ◽

pp. 1849-1860 ◽

Cited By ~ 72

Author(s):

Krishnan Rajeshwar ◽

C. R. Chenthamarakshan ◽

Scott Goeringer ◽

Miljana Djukic

Keyword(s):

Methylene Blue ◽

Visible Light ◽

Hexavalent Chromium ◽

Environmental Remediation ◽

Catalytic Properties ◽

Heterogeneous Photocatalysis ◽

The Other ◽

Tio2 Surface ◽

Tio2 Sample

Using hexavalent chromium [Cr(VI)] and methylene blue (MB) as model substrates, we discuss three aspects of TiO2-based heterogeneous photocatalysis. We show first that a given TiO2 sample may not be simultaneously optimal for photocatalytically driving the reduction of Cr(VI) and the oxidation of MB. We further show that a TiO2 sample that strongly adsorbs either of these substrates in the dark is not optimal as a photocatalyst. The other two aspects concern circumventing the rather poor surface catalytic properties and visible light photoresponse of TiO2, respectively. Strategies revolving around the visible light photoexcitation of the substrate itself and metal-modification of the TiO2 surface, are described as possible solutions.

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Utilization of Composts for Adsorption of Methylene Blue from Aqueous Solutions: Kinetics and Equilibrium Studies

Materials ◽

10.3390/ma13092179 ◽

2020 ◽

Vol 13 (9) ◽

pp. 2179

Author(s):

Remigio Paradelo ◽

Khaled Al-Zawahreh ◽

María Teresa Barral

Keyword(s):

Methylene Blue ◽

Particle Size ◽

Ionic Strength ◽

Municipal Solid Waste ◽

Solid Waste ◽

Environmental Remediation ◽

Dye Removal ◽

Low Cost ◽

Pine Bark ◽

Municipal Solid Waste Compost

Utilization of composts as low-cost adsorbents is an important application in the field of environmental remediation, but these materials have not yet been extensively used for dye removal. In this work, we have studied the characteristics of adsorption of methylene blue onto two composts (a municipal solid waste compost and a pine bark compost). Kinetics and equilibrium batch experiments testing the influence of adsorbent particle size, solution pH and ionic strength were performed. Both composts have a high adsorption capacity for methylene blue, similar to other low-cost adsorbents. Kinetics of adsorption followed a pseudo-first-order model, with maximum adsorption reached after a contact time of two hours. Equilibrium adsorption followed a Langmuir model in general. Reduction of particle size only increased adsorption slightly for composted pine bark. Increase in ionic strength had no effect on adsorption by municipal solid waste compost, but increased adsorption by composted pine bark. Modification of pH between 5 and 7 did not influence adsorption in any case. Overall, the results suggest that electrostatic interaction between the cationic dye and the anionic functional groups in the composts is not the only mechanism involved in adsorption. In conclusion, the use of composts for dye removal is a likely application, in particular for those composts presenting limitations for agricultural use.

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Scalable Fabrication of Metallopolymeric Superstructures for Highly Efficient Removal of Methylene Blue

Nanomaterials ◽

10.3390/nano9071001 ◽

2019 ◽

Vol 9 (7) ◽

pp. 1001 ◽

Cited By ~ 2

Author(s):

Meirong Zhou ◽

Tianyu Yang ◽

Weibin Hu ◽

Xiaohong He ◽

Junni Xie ◽

...

Keyword(s):

Methylene Blue ◽

Metal Ions ◽

Self Assembly ◽

Environmental Remediation ◽

Functional Materials ◽

Maximum Adsorption Capacity ◽

Mixed Solution ◽

Hybrid Functional ◽

Xps Characterization ◽

One Step

Metallopolymeric superstructures (MPS) are hybrid functional materials that find wide applications in environmental, energy, catalytic and biomedical-related scenarios, while their fabrication usually suffers from the complicated polymerization between monomeric ligands and metal ions. In this work, we have developed a facile one-step protocol to fabricate metallopolymeric superstructures with different morphology including nanospheres, nanocubes, nanorods, and nanostars for environmental remediation application. Specifically, we have firstly synthesized the amphiphilic block copolymers (BCP) bearing hydrophobic aromatic backbone and hydrophilic pendent carboxylic/sulfonic groups, which have been subsequently transformed into MPS via the metal ions mediated self-assembly in mixed solution of dimethylformamide (DMF) and H2O. Based on SEM, FTIR, XRD and XPS characterization, we have revealed that the fine morphology and condensed structures of MPS can be modulated via the metal ions and BCP concentration, and the obtained MPS can be employed as efficient adsorbents for the removal of methylene blue with maximum adsorption capacity approaching 936.13 mg/g.

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