scholarly journals Wet Synthesis of Elongated Hexagonal ZnO Microstructures for Applications as Photo-Piezoelectric Catalysts

Materials ◽  
2020 ◽  
Vol 13 (13) ◽  
pp. 2938 ◽  
Author(s):  
Rosanna Pagano ◽  
Chiara Ingrosso ◽  
Gabriele Giancane ◽  
Ludovico Valli ◽  
Simona Bettini
Keyword(s):  
Uv Light ◽  
Low Cost ◽  
Renewable Energy Sources ◽  
Degradation Process ◽  
Blue Dye ◽  
Present Contribution ◽  
Wurtzite Phase ◽  
Photo Degradation ◽  
Uv Photons ◽  
Wet Synthesis

It is well known that energetic demand and environmental pollution are strictly connected; the side products of vehicle and industrial exhausts are considered extremely dangerous for both human and environmental health. In the last years, the possibility to simultaneously photo-degrade water dissolved pollutants by means of ZnO nanostructures and to use their piezoelectric features to enhance the photo-degradation process has been investigated. In the present contribution, an easy and low-cost wet approach to synthetize hexagonal elongated ZnO microstructures in the wurtzite phase was developed. ZnO performances as photo-catalysts, under UV-light irradiation, were confirmed on water dissolved methylene blue dye. Piezoelectric responses of the synthetized ZnO microstructures were evaluated, as well, by depositing them into films onto flexible substrates, and a home-made layout was developed, in order to stimulate the ZnO microstructures deposited on solid supports by means of mechanical stress and UV photons, simultaneously. A relevant increment of the photo-degradation efficiency was observed when the piezopotential was applied, proposing the present approach as a completely eco-friendly tool, able to use renewable energy sources to degrade water solved pollutants.

scholarly journals Fe(III)-Aqua Complex Mediated Photodegradation of Methylene Blue Dye

2021 ◽  
Vol 12 (4) ◽  
pp. 112-117
Author(s):  
Ashfeen Nawar ◽  
◽  
Md. Ataur Rahman ◽  
Md. Mufazzal Hossain
Keyword(s):  
Methylene Blue ◽  
Uv Light ◽  
Low Cost ◽  
Degradation Process ◽  
Aqua Complex ◽  
Blue Dye ◽  
Light Sources ◽  
Experimental Conditions ◽  
Environment Friendly ◽  
Set Up

Industrialization in the current times has become extremely rapid. Some of these industries are responsible for discharging dye-containing wastewater into natural water bodies and hence causing environmental deterioration. The purpose of this research is to investigate an inexpensive and easy-to-set-up photodegradation process for the mineralization of methylene blue (MB) dye. The optimum conditions required for maximum degradation of the dye were explored by varying different experimental parameters such as the initial concentration of Fe(III) and dye, pH of the reaction mixture, nature of light sources, and intensity of ultraviolet (UV) light. Approximately 97% photodegradation of methylene blue was recorded at pH 2.30 for the optimum concentration of MB of 3.00 × 10−5 M and Fe(III) aqueous solution of 8.00 × 10−4 M when irradiated under UV light of intensity 3.31 × 10−9 Ein cm−3 s−1. Under sunlight, with similar experimental conditions, 73% degradation of the dye was achieved. This is an environment-friendly, efficient, and low-cost degradation process of methylene blue.

scholarly journals Degradasi Tirosina Menggunakan Mangkinfoto Berasaskan TiO2

2012 ◽  
Author(s):  
Rusmidah Ali ◽  
Siti Salamah Maisoan @ Selamat
Keyword(s):  
Amino Acid ◽  
Metal Ions ◽  
Uv Light ◽  
Degradation Process ◽  
Aqueous System ◽  
Visible Spectroscopy ◽  
Photo Degradation ◽  
Efficient System ◽  
Catalyst Powder ◽  
Uv Visible

Asid amino merupakan bahan asas dalam tisu tumbuhan dan haiwan. Tirosina (Tr) salah satu jenis asid amino yang mengandungi gelang aromatik, telah dipilih sebagai sampel untuk proses degradasi dalam medium akueus. Ini bertujuan melihat kesan penggunaan mangkinfoto dalam sinaran ultralembayung (λ < 400 nm) atau cahaya matahari ke atas molekul tirosina. Kajian telah dijalankan menggunakan sistem cahaya, mangkin serbuk TiO2, hidrogen peroksida, H2O2 dan ion logam. Penambahan ion logam seperti Ni2+, Cu2+, Ag+, Mn2+, Co2+, Fe2+ dan Cd2+ dan agen pengoksidaan, iaitu hidrogen peroksida adalah untuk mendapatkan kaedah yang paling cekap. Keputusan menunjukkan penambahan H2O2 dan ion Fe2+ dan Ni2+ berjaya meningkatkan kecekapan proses degradasifoto tirosina. Ion Ni2+ memberikan keputusan terbaik berbanding ion-ion lain. Ion Cu2+, Ag+, Mn2+ dan Cd2+ merencat proses degradasi. Keputusan juga menunjukkan cahaya matahari adalah setanding dengan cahaya ultralembayung. Kepekatan H2O2 terbaik adalah 5.0 x 10-2M dan semakin banyak TiO2 digunakan semakin baik peratus degradasi tirosina. Oleh itu kaedah optimum untuk proses degradasifoto ialah Tr 2.5 x 10-4 M + TiO2 + H2O25.0 x 10-3 M + Mn+ 1.0 x 10-2 M. Proses degradasifoto dikaji menggunakan spektroskopi ultralembayung-nampak pada julat panjang gelombang 400-200 nm. Kata kunci: Tirosina; degradasifoto; serbuk TiO; akueus Amino acid is a basic component in plant or animal tissue. Tyrosine (Tr), an amino acid which contains aromatic ring, was chosen as a sample for a photodegradation process in an aqueous system. The purpose of the experiment is to study the effect of photocatalysis under UV (λ < 400 nm) or sunlight on tyrosine. The experiment was carried out by using UV light, catalyst powder (TiO2), hidrogen peroxide H2O2 and metal ions system. The addition of oxidising agent H2O2 and metal ions such as Ni2+, Cu2+, Ag+, Mn2+, Co2+, Fe2+ and Cd2+ were used in order to achieve the most efficient system. Results showed that the system with added H2O2 and metal ions such as Ni2+ and Fe2+ had successfully enhanced the process of the tyrosine photodegradation. Other metal ions system such as Cu2+, Ag+, Mn2+ and Cd2+ were found to inhibit the degradation process. The results also showed that sunlight was comparable to ultraviolet light. The best H2O2 concentration was 5.0 x 10-2 M and the percentage of tyrosine degradation increased with the addition of more TiO2) by mass. Therefore, the optimum condition for tyrosine photodegradation process was in Tr 2.5 x 10-4 M + TiO2 + H2O2 5.0 x 10-3 M + H2O2 1.0 x 10-2 M. The dissappearance of tyrosine in the photo degradation process was monitored by UV-visible spectroscopy between 400-200 nm. Key words: Tyrosine; photodegradation; TiO2 powder; akueus

Synthesis and Characterization Polyaniline/Cobalt Oxide Nanocomposite by Chemical Oxidation Method

2018 ◽  
Vol 1 (1) ◽  
pp. 9-20 ◽  
Author(s):  
M Haridevi ◽  
S Prabu ◽  
M Lakshmi Devi ◽  
E Bhakya Lakshmi ◽  
K Mohanraj ◽  
...  
Keyword(s):  
Cobalt Chloride ◽  
Uv Light ◽  
Low Cost ◽  
Oxidative Polymerization ◽  
Chemical Oxidation ◽  
X Ray Diffraction ◽  
Chemical Oxidative Polymerization ◽  
Photo Degradation ◽  
X Ray ◽  
Polymerization Method

The Co3O4-PANI nanocomposites has been synthesized by chemical oxidative polymerization method using cobalt chloride. It is a simple and low cost method to prepare nanocomposite. The prepared samples were characterized by using Scanning Electron Microscope (SEM), X-ray diffraction (XRD) and Fourier Transform Spectroscopy (FTIR) to get surface morphology, idea of getting particles of nano sized range so that further characterization can be done, to study the net surface charge of the nanoparticles by Zeta potential, photoluminescence of synthesized nanocomposite and measure photocatalytic activity of the synthesized nanomaterials was successfully tested for photo degradation of dye under UV light were studied

scholarly journals Effect of ultraviolet light on the degradation of Low-Density and High-Density Polyethylene characterized by the weight loss and FTIR

2019 ◽  
Vol 1 (2) ◽  
pp. 26-31
Author(s):  
Prakash Bhuyar ◽  
Nurul Aqilah Binti Mohd Tamizi ◽  
Mohd Hasbi Ab. Rahim ◽  
Gaanty Pragas Maniam ◽  
Natanamurugaraj Govindan
Keyword(s):  
Weight Loss ◽  
High Density Polyethylene ◽  
Uv Light ◽  
Incident Light ◽  
Degradation Process ◽  
Sem Analysis ◽  
Ftir Spectrum ◽  
Physical Treatment ◽  
Photo Degradation ◽  
Vibrational Energies

In this study, the research was made to understand the knowledge widely related to the degradation process of polyethylene polymer. The mode of treatment that involves in the degradation process of polyethylene is physical treatment while the method of degradation used is photo-degradation of UV light. By using the physical treatment of UV irradiation light, it helps by affecting the bonding that holds the polymer together to break and weakens the plastic. From the result obtained in FTIR and SEM analysis, in FTIR spectrum of LDPE shows higher transmittance compared to FTIR spectrum of HDPE both UV-treated for 30 days. This indicates the high transmittance have few bonds to absorb light in the LDPE sample, low transmittance in HDPE sample means has high population of bonds which have vibrational energies corresponding to the incident light. For SEM result, the polyethylene for LDPE plastic sheet shows the best results for degradation and managed to reduce the weight loss at 87.5% compared to HDPE plastic which at 21.6%.

Photocatalysis of Coomassie Brilliant Blue Using Clay Mineral

2016 ◽  
Vol 869 ◽  
pp. 765-767 ◽  
Author(s):  
Layane Rodrigues Almeida ◽  
João Sammy Nery Souza ◽  
Edson Cavalcanti Silva Filho ◽  
Josy Anteveli Osajima
Keyword(s):  
Organic Pollutants ◽  
Uv Light ◽  
Brilliant Blue ◽  
Blue Dye ◽  
Secondary Treatment ◽  
Toxic Compounds ◽  
Coomassie Brilliant Blue ◽  
Kinetics Of ◽  
Coomassie Brilliant ◽  
Photocatalytic Processes

The presence of organic pollutants, which cannot be eliminated by conventional processes of primary and secondary treatment, can be problematic. Photocatalytic processes offer an efficient breakdown of organic pollutants into non-toxic compounds such as CO2 and H2O. This paper proposes the use of the titanium dioxide embedded in palygorskite as a photoactive material in the degradation of cationic dye, Coomassie Brilliant Blue. The system was irradiated using UV light for a maximum time of 120 minutes. The concentration of the dye used was 1.0x10-4 mol L-1 in 0.5 g L-1 of the photoactive material. The kinetics of the system was monitored by UV-Vis spectrophotometry. In 120 minutes of radiation, the process of photocatalysis reduced the initial concentration of the Coomassie Brilliant Blue dye in half.

scholarly journals Superior Degradation Performance of Nanoporous Copper Catalysts on Methyl Orange

Metals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 913
Author(s):  
Jinyi Wang ◽  
Sen Yang
Keyword(s):  
Activation Energy ◽  
Methyl Orange ◽  
High Efficiency ◽  
Low Cost ◽  
Degradation Process ◽  
Copper Catalysts ◽  
Reaction Rate Constant ◽  
Nanoporous Structure ◽  
Intra Particle Diffusion ◽  
Different Temperatures

The development of low-cost and high-efficiency catalysts for wastewater treatment is of great significance. Herein, nanoporous Cu/Cu2O catalysts were synthesized from MnCu, MnCuNi, and MnCuAl with similar ligament size through one-step dealloying. Meanwhile, the comparisons of three catalysts in performing methyl orange degradation were investigated. One of the catalysts possessed a degradation efficiency as high as 7.67 mg·g−1·min−1. With good linear fitting by the pseudo-first-order model, the reaction rate constant was evaluated. In order to better understand the degradation process, the adsorption behavior was considered, and it was divided into three stages based on the intra-particle diffusion model. Three different temperatures were applied to explore the activation energy of the degradation. As a photocatalytic agent, the nanoporous structure of Cu/Cu2O possessed a large surface area and it also had low activation energy, which were beneficial to the excellent degradation performance.

Photocatalytic Degradation of Synthetic Sulfur Pollutants in Petroleum Fractions under Different pH and Photocatalyst

2021 ◽  
Vol 02 (01) ◽  
Author(s):  
Mohamad Alif Hakimi Hamdan ◽  
◽  
Nur Hanis Hayati Hairom ◽  
Nurhafisza Zaiton ◽  
Zawati Harun ◽  
...  
Keyword(s):  
Photocatalytic Degradation ◽  
Zno Nanoparticles ◽  
Low Cost ◽  
Industrial Effluents ◽  
Degradation Process ◽  
Vital Role ◽  
Petroleum Fraction ◽  
Precipitation Method ◽  
Synthesis Process ◽  
Petroleum Fractions

Thiophene is one of the sulfur compounds in the petroleum fraction that can be harmful to living things and lead to a critical effect on the ecosystem. Photocatalytic degradation is one of the promising methods in treating wastewater as it can mineralization of pollutants into carbon dioxide and water. Other than that, this method is non-toxic and relatively low cost. The production of hydroxyl radicals playing a vital role in the degradation of organic pollutants. It has been claimed that the usage of zinc oxide (ZnO) nanoparticles could give an excellent degradation process as this photocatalyst have high photosensitivity, low cost and chemically stable. However, the preparation method of ZnO nanoparticles will affect the agglomeration, particle size, shape and morphology of particles and lead to influence the photocatalytic activity in degrading thiophene. Therefore, this study focused on the effectiveness of ZnO nanoparticles in the presence of fibrous nanosilica (KCC-1) and polyethylene glycol (PEG) as the capping agent to degrade synthetic thiophene. ZnO/KCC-1 had been synthesized via the precipitation method and characterized by using Fourier Transform Infrared (FTIR). The chemical bond and nature of the photocatalyst from the FTIR results proved that the synthesis process to produce the ZnO/KCC-1 was succeed. The large surface area of KCC-1 increases the effectiveness of ZnO which is supported by the experimental data. Accordingly, the optimum condition for photocatalytic degradation of thiophene is under pH 7 by using ZnO/KCC-1 as photocatalyst. Hence, it is believed that this research could be implemented to remove the thiophene in petroleum fraction from the actual industrial effluents and this can preserve nature in the future.

A Very Low-Cost, Labor-Efficient, and Simple Method to Block Scattered Ultraviolet Light in PDMS Microfluidic Devices by Inserting Aluminum Foil Strips

2018 ◽  
Vol 11 (1) ◽  
Author(s):  
Shuo Wang ◽  
Peter Shankles ◽  
Scott Retterer ◽  
Yong Tae Kang ◽  
Chang Kyoung Choi
Keyword(s):  
Soft Lithography ◽  
Uv Light ◽  
Low Cost ◽  
Microfluidic Devices ◽  
Aluminum Foil ◽  
Material Synthesis ◽  
Simple Method ◽  
Micro Particles ◽  
Complex Shapes ◽  
The Cost

Abstract Opto-microfluidic methods have advantages for manufacturing complex shapes or structures of micro particles/hydrogels. Most of these microfluidic devices are made of polydimethylsiloxane (PDMS) by soft lithography because of its flexibility of designing and manufacturing. However, PDMS scatters ultraviolet (UV) light, which polymerizes the photocrosslinkable materials at undesirable locations and clogs the microfluidic devices. A fluorescent dye has previously been employed to absorb the scattered UV light and shift its wavelength to effectively solve this issue. However, this method is limited due to the cost of the materials (tens of dollars per microchip), the time consumed on synthesizing the fluorescent material and verifying its quality (two to three days). More importantly, significant expertise on material synthesis and characterization is required for users of the opto-microfluidic technique. The cost of preliminary testing on multiple iterations of different microfluidic chip designs would also be excessive. Alternatively, with a delicate microchannel design, we simply inserted aluminum foil strips (AFS) inside the PDMS device to block the scattered UV light. By using this method, the UV light was limited to the exposure region so that the opto-microfluidic device could consistently generate microgels longer than 6 h. This is a nearly cost- and labor-free method to solve this issue.

Empirical Equilibrium Study on Rice Husk and Eggshells as Low Cost Bioadsorbent for the Methylene Blue Removal

2014 ◽  
Vol 699 ◽  
pp. 221-226
Author(s):  
Nurul Hanim Razak ◽  
Md. Razali Ayob ◽  
M.A.M. Zainin ◽  
M.Z. Hilwa
Keyword(s):  
Methylene Blue ◽  
Rice Husk ◽  
Low Cost ◽  
Agricultural Waste ◽  
Textile Wastewater ◽  
Blue Dye ◽  
Rice Husks ◽  
Equilibrium Study ◽  
Porosity Characterization

Eggshells and rice husk, two types of notable agricultural waste were used as bioadsorbent to remove Methylene Blue dye (MBD) in aqueous solution. This study was to investigate the performance of these two bioadsorbents in removing MBD. The removal percentage, adsorption capacity, and porosity characterization were examined. The method applied was a physical filtration. UV-VIS Spectrophotometer was used to determine the efficiency of the bioadsorbents in MBD adsorption. The highest removal percentage at the most concentrated MBD were 51% and 98% for eggshells and rice husks respectively. Meanwhile the characterization of rice husks pore size and volume proves that higher adsorptivity towards dye compares to eggshells porosity. It was concluded that the eggshells and rice husks bioadsorbents was successful to treat industrial textile wastewater with rice husks as the most efficient bioadsorbent in removing MBD.

Sol-gel-derived gallium nitride thin films for ultraviolet photodetection

2019 ◽  
Vol 36 (1) ◽  
pp. 8-13 ◽  
Author(s):  
Chee Yong Fong ◽  
Sha Shiong Ng ◽  
NurFahana Mohd Amin ◽  
Fong Kwong Yam ◽  
Zainuriah Hassan
Keyword(s):  
Thin Films ◽  
Dark Current ◽  
Uv Light ◽  
Low Cost ◽  
Sol Gel ◽  
Contrast Ratio ◽  
Uv Photodetector ◽  
Content Type ◽  
Barrier Heights ◽  
Coating Method

Purpose This study aims to explore the applicability of the sol-gel-derived GaN thin films for UV photodetection. Design/methodology/approach GaN-based ultraviolet (UV) photodetector with Pt Schottky contacts was fabricated and its applicability was investigated. The current-voltage (I-V) characteristics of the GaN-based UV photodetector under the dark current and photocurrent were measured. Findings The ideality factors of GaN-based UV photodetector under dark current and photocurrent were 6.93 and 5.62, respectively. While the Schottky barrier heights (SBH) for GaN-based UV photodetector under dark current and photocurrent were 0.35 eV and 0.34 eV, respectively. The contrast ratio and responsivity of this UV photodetector measured at 5 V were found to be 1.36 and 1.68 μA/W, respectively. The photoresponse as a function of time was measured by switching the UV light on and off continuously at different forward biases of 1, 3 and 6 V. The results showed that the fabricated UV photodetector has reasonable stability and repeatability. Originality/value This work demonstrated that GaN-based UV photodetector can be fabricated by using the GaN thin film grown by low-cost and simple sol-gel spin coating method.

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