scholarly journals Synthesis of N-Doped ZnO Nanocomposites for Sunlight Photocatalytic Degradation of Textile Dye Pollutants

2020 ◽  
Vol 4 (2) ◽  
pp. 49 ◽  
Author(s):  
Rowshon Kabir ◽  
Md. Abu Khalid Saifullah ◽  
Abrar Zadeed Ahmed ◽  
Shah Md. Masum ◽  
Md. Ashraful Islam Molla
Keyword(s):  
Photocatalytic Degradation ◽  
Low Cost ◽  
Nir Spectroscopy ◽  
Cost Effective ◽  
Infrared Region ◽  
Textile Dye ◽  
X Ray Diffraction ◽  
Sunlight Irradiation ◽  
Dye Pollutants ◽  
Doped Zno

Undoped and N-doped ZnO nanocomposites are produced by a simple and low-cost mechanochemical method. The characterizations of all nanocomposites are examined by X-ray diffraction (XRD), Fourier transform-infrared (FT-IR), scanning electron microscopy (SEM) and UV-Vis-NIR spectroscopy. The XRD measurements show that the crystal sizes of undoped and N-doped ZnO nanocomposites are ~29 and ~28 nm, respectively. The UV-Vis-NIR spectroscopy results illustrate that the transmittance of the 7 wt% N/ZnO in the visible and infrared region is a bit higher than the undoped ZnO. The photocatalytic activity of undoped and N-doped ZnO nanocomposites is investigated for the degradation of Methylene Blue (MB) and Rhodamine B (RhB) aqueous solution with direct sunlight irradiation. The photocatalytic degradation percentages with 7 wt% N/ZnO for 5 and 10 mg/L MB dye solution are found to be 93.70% and 98.11%, respectively, whereas 78.40% and 89.15% degradation percentages are found with undoped ZnO, after 3 h sunlight irradiation. Under the same conditions, the photocatalytic degradation value of RhB dye (10 mg/L) solution is measured to be 86.21% for 7 wt% N/ZnO and 64.75% for undoped ZnO. The N-doped ZnO nanocomposites are found to exhibit enhanced photocatalytic performance for both dyes’ degradation under sunlight irradiation in comparison with the undoped ZnO. Therefore, the photocatalytic degradation treatment of wastewater including dye pollutants with sunlight is an easy and simple technique, and cost-effective.

Effect of Morphology on Near-Infrared Shielding Properties of Aluminum-Doped ZnO by Solvothermal Synthesis

2020 ◽  
Vol 1007 ◽  
pp. 148-153
Author(s):  
Pimpaka Putthithanas ◽  
Supan Yodyingyong ◽  
Jeerapond Leelawattanachai ◽  
Wannapong Triampo ◽  
Noppakun Sanpo ◽  
...  
Keyword(s):  
Near Infrared ◽  
Low Cost ◽  
Hexagonal Wurtzite Structure ◽  
Infrared Region ◽  
X Ray Diffraction ◽  
Smart Window ◽  
Doped Zno ◽  
Heat Shielding ◽  
Xrd Patterns ◽  
Potential Use

In this work, aluminum-doped ZnO (AZO) is synthesized for heat-shielding applications. A family of ethanolamine (EA: monoethanolamine (MEA), diethanolamine (DEA), and triethanolamine TEA)) is used to control the morphology of aluminum-doped ZnO (AZO) synthesized via a simple solvothermal method at the temperature of 120°C for 6 h. The samples were characterized by field-emission scanning electron microscopy (FE-SEM). The formation of primary ZnO nanoparticles (NPs) showed that TEA yielded highly packed-spherical aggregates not found when DEA and MEA were used. X-ray diffraction (XRD) found that all AZO samples have peaks of the ZnO hexagonal wurtzite structure. XRD patterns of aluminum were found for >10 mol%. UV-Vis-NIR spectrophotometer was used to study the optical property and heat-shielding of the near-infrared region (NIR, the wavelength from 700 - 2500 nm). All AZO NPs of 0, 2, 4, and 10 mol% exhibited strong NIR shielding ability up to 80% insulation. From these results, the AZO NPs have potential use as NIR shielding materials of low-cost and simple processes to be coated on an energy-efficient window as smart window coating in buildings and automotive thus reducing energy consumption, especially in air conditioning usage.

scholarly journals Sensing Performance of Al and Sn Doped ZnO for Hydrogen Detection

Proceedings ◽  
2019 ◽  
Vol 14 (1) ◽  
pp. 39
Author(s):  
Zahira. El khalidi ◽  
Maryam Siadat ◽  
Elisabetta. Comini ◽  
Salah. Fadili ◽  
Philippe. Thevenin
Keyword(s):  
Zinc Oxide ◽  
Chemical Sensor ◽  
Low Cost ◽  
Zinc Powder ◽  
Health Condition ◽  
Vibration Modes ◽  
X Ray Diffraction ◽  
Grain Sizes ◽  
Pure Oxide ◽  
Doped Zno

Chemical gas sensors were studied long ago and nowadays, for the advantageous role they provide to the environment, health condition monitoring and protection. The recent studies focus on the semiconductors sensing abilities, especially of non toxic and low cost compounds. The present work describes the steps to elaborate and perform a chemical sensor using intrinsic and doped semiconductor zinc oxide. First, we synthesized pure oxide using zinc powder, then, two other samples were established where we introduced the same doping percentage of Al and Sn respectively. Using low cost spray pyrolysis, and respecting the same conditions of preparation. The obtained samples were then characterized by X Ray Diffraction (XRD) that revealed the hexagonal wurzite structure and higher crystallite density towards the direction (002), besides the appearance of the vibration modes related to zinc oxide, confirmed by Raman spectroscopy. SEM spectroscopy showed that the surface morphology is ideal for oxidizing/reduction reactions, due to the porous structure and the low grain sizes, especially observed for the sample Sn doped ZnO. The gas testing confirms these predictions showing that the highest response is related to Sn doped ZnO compared to ZnO and followed by Al doped ZnO. The films exhibited responses towards: CO, acetone, methanol, H2, ammonia and NO2. The concentrations were varied from 10 to 500 ppm and the working temperatures from 250 to 500°C, the optimal working temperatures were 350 and 400 °C. Sn doped ZnO showed a high response towards H2 gas target, with a sensitivity reaching 200 at 500 ppm, for 400 °C.

Low-cost thermo-chemical process of TiO2 powder purification: Study of iterative gettering effect

2021 ◽  
Author(s):  
Nesrine Jaouabi ◽  
Wala Medfai ◽  
Marouan Khalifa ◽  
Rabia Zaghouani ◽  
Hatem Ezzaouia
Keyword(s):  
Porous Layer ◽  
Sacrificial Layer ◽  
Low Cost ◽  
Nir Spectroscopy ◽  
Tio2 Powder ◽  
X Ray Diffraction ◽  
X Ray ◽  
Density Reduction ◽  
Transmission Electron ◽  
Layer Effect

The titanium dioxide (TiO2) purity is very important for the TiO2-based applications making essential the impurities density reduction. In this study, we propose an efficient purification process of TiO2 powder in order to reduce impurities. The low-cost proposed approach is based on an iterative gettering (IG) process combining three main steps: (1) a porous TiO2 sacrificial layer formation (p-TiO2), (2) a rapid thermal annealing (RTA) of p-TiO2 powder in an infrared oven at 950°C under air permitting the residual impurities diffusion to the porous layer surface and (3) etching in acid solution to remove the porous layer. Effect of the proposed gettering process on purification efficiency was evaluated by different characterization techniques such as the transmission electron microscopy (TEM), the energy dispersive x-ray spectroscopy (EDX), the UV–Visible-NIR spectroscopy, the X-ray diffraction (XRD) and atomic absorption spectroscopy (AAS). The obtained results showed the efficient removal of metal impurities, such as Cu, Al, P, and Fe confirming the efficiency of the process improving the purity from 89% to 99.96%.

scholarly journals Preparation of ternary ZnO/Ag/cellulose and its enhanced photocatalytic degradation property on phenol and benzene in VOCs

2019 ◽  
Vol 17 (1) ◽  
pp. 779-787 ◽  
Author(s):  
Xiao-Hang Zou ◽  
Si-Wei Zhao ◽  
Ji-Guo Zhang ◽  
Hui-Liang Sun ◽  
Qing-Jiang Pan ◽  
...  
Keyword(s):  
Photocatalytic Degradation ◽  
Separation Efficiency ◽  
Uv Light ◽  
Low Cost ◽  
Visible Region ◽  
X Ray Diffraction ◽  
Ternary Composite ◽  
Photogenerated Electrons ◽  
Excellent Photocatalytic Activity ◽  
Diffraction Patterns

AbstractThe ZnO/Ag/cellulose composite (ZAC) with excellent photocatalytic activity of degrading benzene and phenol in VOCs has been successfully synthesized. EDS, TEM, XPS and UV-vis analyses show that the ZAC is a ternary composite. It is composed of Ag, ZnO and cellulose, where the cellulose works as the substrate to anchor the other two components. The X-ray diffraction patterns find well-crystallized ZnO nanoparticles. Multiple PL peaks in the visible region measured for ZAC, imply rich defects on ZnO. It is observed that Ag nanoparticles are mainly attached on ZnO in the composite, which would raise the separation efficiency of photogenerated electrons and holes. Photocatalytic degradation shows that ZAC is able to decompose almost 100% phenol and 19% benzene in VOCs under UV light irradiation (6 W) which is almost no harm to human body. Due to the renewable cellulose, our ternary composite ZAC imparts low-cost, easily recycled and flexible merits, which might be applied in the indoor VOCs treatment.

scholarly journals Visible-Light-Driven SO42-/TiO2 Photocatalyst Synthesized from Binh Dinh (Vietnam) Ilmenite Ore for Rhodamine B Degradation

2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Tan Lam Nguyen ◽  
Viet Dinh Quoc ◽  
Thi Lan Nguyen ◽  
Thi Thanh Thuy Le ◽  
Thanh Khan Dinh ◽  
...  
Keyword(s):  
Visible Light ◽  
Specific Surface ◽  
Photocatalytic Degradation ◽  
Surface Area ◽  
Rhodamine B ◽  
Low Cost ◽  
Tio2 Photocatalyst ◽  
Tio2 Sample ◽  
Sunlight Irradiation ◽  
Visible Light Driven

A low-cost and simplistic approach for the synthesis of nanosized SO42-/TiO2 photocatalyst was successfully performed using Binh Dinh ilmenite ore and H2SO4 as titanium and sulfur sources, respectively. The experimental results indicate that the obtained material exists in the form of particles with a size of about 22 nm and has a specific surface area of about 49 m2 g-1. Compared with the TiO2 sample, the SO42-/TiO2 sample shows much higher photocatalytic degradation of rhodamine B (RhB) under the sunlight irradiation. In more details, the nanosized SO42-/TiO2 sample obtained is capable of completely decomposing RhB after 9 hours of irradiation by a 60 W LED lamp with a corresponding intensity of 9,500 Lux. However, when the SO42-/TiO2 is irradiated by the sunlight with the intensity of 65,000 Lux, it only takes 2 hours to completely decompose rhodamine B (RhB), facilitating the use of SO42-/TiO2 as a potential photocatalyst for the RhB photodegradation.

Synthetic Route of CdSe Nanocrystalline Films Fabricated by Substrate Vibration Assisted Drop Casting Method

2020 ◽  
Vol 12 (6) ◽  
pp. 761-770
Author(s):  
Megha Sachdeva ◽  
P. Agrawal ◽  
Sheenam Sachdeva ◽  
K. K. Bhasin ◽  
S. K. Tripathi ◽  
...  
Keyword(s):  
Low Cost ◽  
Cost Effective ◽  
Cdse Nanocrystals ◽  
Nanocrystalline Films ◽  
X Ray Diffraction ◽  
Casting Method ◽  
Substrate Vibration ◽  
Ultrasonic Substrate Vibration ◽  
Particle Size Analyzer ◽  
Average Size

Herein, we report a greener, non-toxic, cost effective and a modest scheme for the fabrication of excellent CdSe nanocrystals (NCs). Precursors for the present reaction are synthesized by the treatment of cadmium chloride (CdCl2) with 2-pyridyl selenolate (NaSeC5H4N) resulting a complex of the formula [(C5H4NSe)2Cd]. The complex is characterized by NMR (1H and 13C) and IR spectroscopies. The complex, [(C5H4NSe)2Cd] is found to be polymeric in nature, as indicated by its insolubility in solvents, and is further customized as a single-source pioneers for the preparation of colloidal CdSe NCs. Thermolysis of [(C5H4NSe)2 Cd] has been successfully carried out by hotinjection method using low-cost and harmless oleic acid (OA) as the coordinating solvent, thereby rejecting the need of air-sensitive and toxic solvents. Based upon dynamic light scattering (DLS) technique, the average size of colloidal CdSe NCs are determined using particle size analyzer. The average size of colloidal NCs comes out to be 6.3 nm. Thin films of colloidal CdSe NCs are deposited on glass substrate using drop-casting (DC) and ultrasonic substrate vibration assisted drop casting (SVADC) methods to study their use as workable materials for engineering devices. The films are characterized by ultraviolet-visible spectroscopy (UV-vis), photoluminescence (PL) studies, X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques.

scholarly journals Synthesis of CuO/ZnO Nanocomposites and Their Application in Photodegradation of Toxic Textile Dye

2019 ◽  
Vol 3 (3) ◽  
pp. 91 ◽  
Author(s):  
Abdullah Al Mamun Sakib ◽  
Shah Md. Masum ◽  
Jan Hoinkis ◽  
Rafiqul Islam ◽  
Md. Ashraful Islam Molla
Keyword(s):  
Textile Wastewater ◽  
Combustion Method ◽  
Solar Irradiation ◽  
Textile Dye ◽  
Oh Radicals ◽  
X Ray Diffraction ◽  
Sunlight Irradiation ◽  
X Ray ◽  
Zno Crystal ◽  
Direct Solar Irradiation

CuO/ZnO composites are synthesized using a simple mechanochemical combustion method. X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and Fourier transform infrared (FTIR) are used to characterize the prepared oxides. X-ray diffraction reveals that the prepared CuO/ZnO exhibit a wurtzite ZnO crystal structure and the composites are composed of CuO and ZnO. The strong peaks of the Cu, Zn, and O elements are exhibited in the EDX spectrum. The FTIR spectra appear at around 3385 cm−1 and 1637 cm−1, caused by O–H stretching, and 400 cm−1 to 590 cm−1, ascribable to Zn–O stretching. The photocatalytic performances of CuO/ZnO nanocomposites are investigated for the degradation of methylene blue (MB) aqueous solution in direct solar irradiation. The degradation value of MB with 5 wt % CuO/ZnO is measured to be 98%, after 2 h of solar irradiation. The reactive •O2− and •OH radicals play important roles in the photodegradation of MB. Mineralization of MB is around 91% under sunlight irradiation within 7 h. The photodegradation treatment for the textile wastewater using sunlight is an easy technique—simply handled, and economical. Therefore, the solar photodegradation technique may be a very effective method for the treatment of wastewater instead of photodegradation with the artificial and expensive Hg-Xe lamp.

scholarly journals SERS Effect on Spin-Coated Seeding of Tilted Au-ZnO Nanorods for Low-Cost Diagnosis

Materials ◽  
2020 ◽  
Vol 13 (23) ◽  
pp. 5321
Author(s):  
Miyeon Jue ◽  
Chan-Gi Pack ◽  
Seakhee Oh ◽  
Bjorn Paulson ◽  
Kwanhee Lee ◽  
...  
Keyword(s):  
Low Cost ◽  
Zno Nanorods ◽  
Cost Effective ◽  
Surface Enhanced Raman Spectroscopy ◽  
Angular Distributions ◽  
Zno Nanorod ◽  
X Ray Diffraction ◽  
Raman Enhancement ◽  
Surface Enhanced Raman ◽  
Increased Sensitivity

Uniformly parallel Au-coated ZnO nanorods have previously been shown to amplify local Raman signals, providing increased sensitivity to disease markers in the detection of inflammation and cancer. However, practical and cost-effective fabrication methods of substrates for surface-enhanced Raman spectroscopy (SERS) fail to produce highly uniform surfaces. Here, the feasibility of Raman enhancement on less-uniform substrates is assessed. ZnO nanorod structures were fabricated by hydrothermal synthesis, starting from spin-coated seed substrates. Following analysis, the nanostructures were coated with Au to create stochastically variant substrates. The non-uniformity of the fabricated Au-coated ZnO nanorod structures is confirmed morphologically by FE-SEM and structurally by X-ray diffraction, and characterized by the angular distributions of the nanorods. Monte Carlo finite element method simulations matching the measured angular distributions and separations predicted only moderate increases in the overall Raman enhancement with increasing uniformity. Highly variant substrates exhibited approximately 76% of the Raman enhancement of more uniform substrates in simulations and experiments. The findings suggest that, although highly inhomogeneous Au-coated ZnO nanorod substrates may not attain the same Raman enhancement as more uniform substrates, the relaxation of fabrication tolerances may be economically viable.

Preferentially grown nanostructured iron disulfide (FeS2) for removal of industrial pollutants

RSC Advances ◽  
2016 ◽  
Vol 6 (101) ◽  
pp. 99120-99128 ◽  
Author(s):  
Gurpreet Kaur ◽  
Bikramjeet Singh ◽  
Paviter Singh ◽  
Manpreet Kaur ◽  
Karmjeet Kaur Buttar ◽  
...  
Keyword(s):  
Methylene Blue ◽  
Hydrothermal Method ◽  
Low Cost ◽  
Cost Effective ◽  
Textile Dye ◽  
Industrial Pollutants ◽  
Iron Disulfide

Preferentially grown nanostructured iron disulfide pyrite (111) was successfully synthesized using a low cost effective hydrothermal method, then employed as a photocatalyst for degradation of methylene blue and the textile dye Synazol Yellow K-HL.

scholarly journals Synthesis of Green Deep Eutectic Solvents for Pretreatment Wheat Straw: Enhance the Solubility of Typical Lignocellulose

2022 ◽  
Vol 14 (2) ◽  
pp. 657
Author(s):  
Zedong Teng ◽  
Liyan Wang ◽  
Bingqian Huang ◽  
Yue Yu ◽  
Jianwei Liu ◽  
...  
Keyword(s):  
Wheat Straw ◽  
Removal Rate ◽  
Low Cost ◽  
Covalent Bond ◽  
Crystallinity Index ◽  
Cost Effective ◽  
Deep Eutectic Solvents ◽  
X Ray Diffraction ◽  
Total Sugar Concentration ◽  
The Cost

Deep eutectic solvents (DESs), a novel and environmentally-friendly solvent, have high potential for biomass pretreatment due to its advantages of low cost, low toxicity, strong solubility, excellent selectivity and biocompatibility. Two types of DES (binary and ternary) were synthesized and characterized, and optimized ternary DES was selected to pretreat wheat straw for enhancement of the solubility of lignocellulose. Moreover, enzymatic hydrolysis was tested to verify the performance of pretreatment. In addition, the changes in surface morphology, structure and crystallinity of wheat straw pretreated by DES were analyzed to reveal the pretreatment mechanism. Experimental results indicated that viscosity exhibited little difference in different types of DESs, and a declining trend as the temperature increases in same DES. The ternary DES pretreatment efficiently enhanced the solubility of typical lignocellulose, with the optimal removal rate of lignin at approximately 69.46%. Furthermore, the total sugar concentration of the residue was about 5.1 times more than that of untreated wheat straw after the pretreated samples were hydrolyzed by the cellulase for 24 h, indicating that DES has the unique ability to selectively extract lignin and hemicellulose from wheat straw while retaining cellulose, and thus enhanced the solubility of lignocellulose. The scanning electron microscope (SEM) observation and X-ray diffraction (XRD) determination showed that the surface of wheat straw suffered from serious erosion and the crystallinity index of wheat straw increased after DES5 pretreatment. Therefore, DES cleaves the covalent bond between lignin and cellulose and hemicellulose, and reduces the intractability of lignin resulting in the lignin dissolution. It suggests that DES can be used as a promising and biocompatible pretreatment way for the cost-effective conversion of lignocellulose biomass into biofuels.

Sign in / Sign up

Export Citation Format

Share Document