Use of Hydroxyl Radical Yield to Investigate a Urea and Cobalt Modified TiO2 Photocatalyst Degrading Rhodamine B under UV and Visible Light

2013 ◽  
Vol 773 ◽  
pp. 595-600 ◽  
Author(s):  
Jyun Hong Shen ◽  
Pei Chi Lu ◽  
Jao Jia Horng
Keyword(s):  
Visible Light ◽  
Hydroxyl Radical ◽  
Rhodamine B ◽  
High Efficiency ◽  
Fluorescence Probe ◽  
Sol Gel ◽  
Ultra Violet ◽  
Quantum Yields ◽  
Toc Removal ◽  
Catalytic Experiment

Material modification of TiO2 photo-catalyst (NMTi) by doping urea and cobalt via sol-gel method was used to achieve high efficiency degradation of rhodamine B (RhB) under visible light (Vis). Although good removal (up to 42% of TOC removed) of RhB by Degussa P25 under ultra violet irradiation, P25 did not effectively degrade RhB (up to 14% TOC removed) under Vis. In the batch photo-catalytic experiment with Vis irradiation, the removal efficiencies of absorbance and TOC by NMTi were 28 and 30%. We used terephthalic acid as fluorescence probe to catch hydroxyl radical (OH) and calculated their quantum yields. The OH yields of NMTi with Vis irradiating was 8.91×10-6 while P25 of 2.65×10-6 (P25 of 1.44×10-5 and NMTi of 1.00×10-5 under UV). The OH yields of NMTi were higher than that of P25 under Vis, but otherwise under UV irradiation. Therefore, our new composited NMTi was more effective than P25 under Vis for both absorbance and TOC removal of RhB. It seemed possessed the application potential under Vis irradiation.

scholarly journals Photocatalytic Performance of SiO2/CNOs/TiO2 to Accelerate the Degradation of Rhodamine B under Visible Light

Nanomaterials ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 1671 ◽  
Author(s):  
Weike Zhang ◽  
Yanrong Zhang ◽  
Kai Yang ◽  
Yanqing Yang ◽  
Jia Jia ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Visible Light ◽  
Rhodamine B ◽  
Photoelectron Spectroscopy ◽  
Degradation Rate ◽  
Photocatalytic Performance ◽  
Sol Gel ◽  
X Ray Diffraction ◽  
X Ray ◽  
Electronic Microscope

A silicon dioxide/carbon nano onions/titanium dioxide (SiO2/CNOs/TiO2) composite was synthesized by a simple sol-gel method and characterized by the methods of X-ray diffraction (XRD), scanning electronic microscope (SEM), X-ray photoelectron spectroscopy (XPS), Brunauer–Emmett–Teller (BET), Fourier transform infrared (FTIR), thermogravimetric analysis (TG), differential scanning calorimeter (DSC) and UV-Vis diffuse reflectance spectra (UV-Vis DRS). In this work, the photocatalytic activity of the SiO2/CNOs/TiO2 photocatalyst was assessed by testing the degradation rate of Rhodamine B (RhB) under visible light. The results indicated that the samples exhibited the best photocatalytic activity when the composite consisted of 3% CNOs and the optimum dosage of SiO2/CNOs/TiO2(3%) was 1.5 g/L as evidenced by the highest RhB degradation rate (96%). The SiO2/CNOs/TiO2 composite greatly improved the quantum efficiency of TiO2. This work provides a new option for the modification of subsequent nanocomposite oxide nanoparticles.

scholarly journals BiOCl/TiO2/diatomite composites with enhanced visible-light photocatalytic activity for the degradation of rhodamine B

2019 ◽  
Vol 10 ◽  
pp. 1412-1422 ◽  
Author(s):  
Minlin Ao ◽  
Kun Liu ◽  
Xuekun Tang ◽  
Zishun Li ◽  
Qian Peng ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Visible Light ◽  
Visible Light Irradiation ◽  
Rhodamine B ◽  
Sol Gel ◽  
Catalytic Performance ◽  
Light Irradiation ◽  
Molar Ratio ◽  
Visible Light Photocatalytic Activity ◽  
Visible Light Photocatalytic

A BiOCl/TiO2/diatomite (BTD) composite was synthesized via a modified sol–gel method and precipitation/calcination method for application as a photocatalyst and shows promise for degradation of organic pollutants in wastewater upon visible-light irradiation. In the composite, diatomite was used as a carrier to support a layer of titanium dioxide (TiO2) nanoparticles and bismuth oxychloride (BiOCl) nanosheets. The results show that TiO2 nanoparticles and BiOCl nanosheets uniformly cover the surface of diatomite and bring TiO2 and BiOCl into close proximity. Rhodamine B was used as the target degradation product and visible light (λ > 400 nm) was used as the light source for the evaluation of the photocatalytic properties of the prepared BTD composite. The results show that the catalytic performance of the BTD composite under visible-light irradiation is much higher than that of TiO2 or BiOCl alone. When the molar ratio of BiOCl to TiO2 is 1:1 and the calcination temperature is 400 °C, the composite was found to exhibit the best catalytic effect. Through the study of the photocatalytic mechanism, it is shown that the strong visible-light photocatalytic activity of the BTD composite results mainly from the quick migration of photoelectrons from the conduction band of TiO2/diatomite to the surface of BiOCl, which promotes the separation effect and reduces the recombination rate of the photoelectron–hole pair. Due to the excellent catalytic performance, the BTD composite shows great potential for wide application in the field of sewage treatment driven by solar energy.

scholarly journals Solar-driven photocatalytic decomposition of microcystin-LR: from laboratory development to on-site demonstration

2017 ◽  
Vol 17 (6) ◽  
pp. 1722-1729 ◽  
Author(s):  
Hesam Zamankhan Malayeri ◽  
Mallikarjuna Nadagouda ◽  
Hyeok Choi
Keyword(s):  
Visible Light ◽  
Real Time ◽  
Tio2 Film ◽  
Organic Contaminants ◽  
Harmful Algal Blooms ◽  
Algal Blooms ◽  
High Efficiency ◽  
Sol Gel ◽  
Photocatalytic Decomposition ◽  
Sol Gel Synthesis

Abstract Harmful algal blooms (HABs) found in various water bodies worldwide have been a huge concern due to their adverse impacts on human health and ecosystems. In particular, HABs associated with cyanobacteria have been of great interest because of their potential to generate and release biological toxins, especially, lethal microcystins (MCs). The overall goal of this study was to develop a new sustainable approach to decompose MCs, preferably on-site and in real-time with minimal effort, fewer chemicals, and low energy inputs. To achieve the goal, a high efficiency nitrogen-doped TiO2 photocatalytic film immobilized onto a glass substrate was fabricated via integrated sol-gel synthesis employing nitrogen-containing surfactants as pore-templating agent and nitrogen-dopant. The film exhibited visible light-activated, nanoporous, and transparent properties. Effects of surfactant type, calcination temperature, coating layers, and reaction pH on the photocatalytic decomposition of microcystin-LR (MC-LR) were investigated under visible light. Eventually, the TiO2 film was able to successfully decompose MC-LR on-site in a lake under solar radiation in real-time. This study implies the high potential of the TiO2 film for on-site and real-time decomposition of many organic contaminants in water by using sustainable solar energy.

A one-step nonaqueous sol–gel route to mixed-phase TiO2with enhanced photocatalytic degradation of Rhodamine B under visible light

CrystEngComm ◽  
2016 ◽  
Vol 18 (11) ◽  
pp. 1964-1975 ◽  
Author(s):  
Xu Liu ◽  
Yuxiu Li ◽  
Dongyang Deng ◽  
Nan Chen ◽  
Xinxin Xing ◽  
...  
Keyword(s):  
Visible Light ◽  
Photocatalytic Degradation ◽  
Rhodamine B ◽  
Sol Gel ◽  
Mixed Phase ◽  
One Step

scholarly journals Development of Smart Composites Based on Doped-TiO2 Nanoparticles with Visible Light Anticancer Properties

Materials ◽  
2019 ◽  
Vol 12 (16) ◽  
pp. 2589 ◽  
Author(s):  
Evdokia Galata ◽  
Eleni A. Georgakopoulou ◽  
Maria-Emmanouela Kassalia ◽  
Nefeli Papadopoulou-Fermeli ◽  
Evangelia A. Pavlatou
Keyword(s):  
Visible Light ◽  
Tio2 Nanoparticles ◽  
Visible Light Irradiation ◽  
Sol Gel ◽  
Ultra Violet ◽  
Light Irradiation ◽  
Composite Particles ◽  
Doped Tio2 ◽  
X Ray ◽  
Anticancer Properties

In this study, the synthesis of smart, polymerically embedded titanium dioxide (TiO2) nanoparticles aimed to exhibit photo-induced anticancer properties under visible light irradiation is investigated. The TiO2 nanoparticles were prepared by utilizing the sol gel method with different dopants, including nitrogen (N-doped), iron (Fe-doped), and nitrogen and iron (Fe,N-doped). The dopants were embedded in an interpenetrating (IP) network microgel synthesized by stimuli responsive poly (N-Isopropylacrylamide-co-polyacrylicacid)–pNipam-co-PAA forming composite particles. All the types of produced particles were characterized by X-ray powder diffraction, micro-Raman, Fourier-transform infrared, X-ray photoelectron, ultra-violet-visible spectroscopy, Field Emission Scanning Electron, Transmission Electron microscopy, and Dynamic Light Scattering techniques. The experimental findings indicate that the doped TiO2 nanoparticles were successfully embedded in the microgel. The N-doped TiO2 nano-powders and composite particles exhibit the best photocatalytic degradation of the pollutant methylene blue under visible light irradiation. Similarly, the highly malignant MDA-MB-231 breast cancer epithelial cells were susceptible to the inhibition of cell proliferation at visible light, especially in the presence of N-doped powders and composites, compared to the non-metastatic MCF-7 cells, which were not affected.

scholarly journals Synthesis and characterization of Fe-TiO2@SiO2@Fe3O4 magnetic visible light photocatalyst for removal of Rhodamine B dye

2021 ◽  
Vol 10 (2) ◽  
pp. 78-83
Author(s):  
Tien Nguyen Thi Thuy ◽  
Do Tran Dang ◽  
Viet Nguyen Minh ◽  
Ngoc Ha Minh ◽  
Minh Dang Nhat ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Visible Light ◽  
Rhodamine B ◽  
Sol Gel ◽  
Photogenerated Electron ◽  
Band Gap Energy ◽  
X Ray Diffraction ◽  
Visible Light Photocatalyst ◽  
Magnetic Curve ◽  
Co Precipitation

In this research, the magnetic visible light photocatalyst of Fe-TiO2@SiO2@Fe3O4 was synthesised using co-precipitation, sol-gel and hydrothermal method. The as-obtained material’s properties were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), diffuse reflectance spectra (UV- Vis), magnetic curve (VSM) and photoluminescence (PL). The catalytic activity of the materials under visible light was investigated for degradation of Rhodamine B pigment  in water. The obtained results indicated that at the catalyst dose of 0.5 g/L, Fe-TiO2@SiO2@Fe3O4 with TiO2/SiO2@Fe3O4 (SF) ratio of 2:1 performed the highest efficiency of  99.3 % after 180 minutes under irritation. The enhanced photocatalytic performance of Rhodamine B under visible light could be ascribed to the reducing of band gap energy and decrease in the recombination rate of photogenerated electron/hole pairs. The catalytic activity after four times of recycling were 71,3 %.The material showed potential for further application in water treatment.

Visible light photoelectrocatalytic degradation of rhodamine B using a dye-sensitised TiO2 electrode

2014 ◽  
Vol 68 (9) ◽  
Author(s):  
Sayekti Wahyuningsih ◽  
Candra Purnawan ◽  
Puspa Kartikasari ◽  
Novita Praistia
Keyword(s):  
Titanium Dioxide ◽  
Visible Light ◽  
Rhodamine B ◽  
Indium Tin Oxide ◽  
Sol Gel ◽  
Tio2 Electrode ◽  
Conductive Glass ◽  
Photoelectrocatalytic Degradation ◽  
Nacl Concentration ◽  
Sol Gel Process

AbstractTitanium dioxide is a promising catalyst for application in the photodegradation of organic pollutants in water due to its powerful oxidising property and long-term photostability. This study presents the production of titanium dioxide using the sol-gel process, dye sensitisation of the TiO2 electrode, and the performance of that cell. Sensitisation of titanium dioxide was performed using a dye, i.e., Fe(II)-polypyridyl complexes. The photoelectrocatalytic degradation of rhodamine B (RB) using ITO/TiO2/dye as electrode was investigated via a series of potentials, from +1.0 V to −1.0 V, and at various pH and NaCl concentration values (ITO is indium tin oxide conductive glass). The photoelectrocatalytic degradation of RB was performed with a visible light lamp. The change in the absorbance of RB with various potentials indicated that the absorbance of RB in solution systems with the sensitised TiO2 electrodes decreased with increasing anodic potential bias. The degradation cell exhibited better performance when the positive anodic bias was applied. The pH values of RB in solution systems also influence the photoelectrodegradation process because of the different RB species present. NaCl concentration also affects the activity of RB photoelectrocatalytic degradation due to changes in the ionic strength character of the electrolyte.

scholarly journals Enhanced Degradation of Rhodamine B by Metallic Organic Frameworks Based on NH2-MIL-125(Ti) under Visible Light

Materials ◽  
2021 ◽  
Vol 14 (24) ◽  
pp. 7741
Author(s):  
Hong-Tham Nguyen Thi ◽  
Kim-Ngan Tran Thi ◽  
Ngoc Bich Hoang ◽  
Bich Thuy Tran ◽  
Trung Sy Do ◽  
...  
Keyword(s):  
Visible Light ◽  
Rhodamine B ◽  
Diffuse Reflectance ◽  
High Efficiency ◽  
Diffuse Reflectance Spectroscopy ◽  
Active Species ◽  
X Ray Diffraction ◽  
X Ray ◽  
Fundamental Properties ◽  
Adsorption Desorption

Samples of the bimetallic-based NH2-MIL-125(Ti) at a ratio of Mn+/Ti4+ is 0.15 (Mn+: Ni2+, Co2+ and Fe3+) were first synthesized using the solvothermal method. Their fundamental properties were analyzed by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman spectra, scanning electron microscopy (SEM), N2 adsorption–desorption measurements, and UV–Vis diffuse reflectance spectroscopy (UV-Vis DRS). The as-acquired materials were used as high-efficiency heterogeneous photocatalysts to remove Rhodamine B (RhB) dye under visible light. The results verified that 82.4% of the RhB (3 × 10−5 M) was degraded within 120 min by 15% Fe/Ti−MOFs. Furthermore, in the purpose of degrading Rhodamine B (RhB), the rate constant for the 15% Fe/Ti-MOFs was found to be 2.6 times as fast as that of NH2-MIL-125(Ti). Moreover, the 15% Fe/Ti-MOFs photocatalysts remained stable after three consecutive cycles. The trapping test demonstrated that the major active species in the degradation of the RhB process were hydroxyl radicals (HO∙) and holes (h+).

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