TiO2 Degussa Research Articles

Enhanced Oxygen Reduction Reaction Via Oxygen Vacancy‐Rich Silica‐Supported Ag/Pd Nanoshells

AbstractHerein, we demonstrated the fine‐tuning of catalysts’ active phase by employing AgPd nanoshells with distinct Ag/Pd ratios synthesized via a galvanic replacement method for the oxygen reduction reaction (ORR). However, more interestingly, the subsequent immobilization of such Ag/Pd ratios onto silica further influenced the support characteristics, creating an increasing concentration of oxygen vacancies in this typically inert support — a surprising and unparalleled outcome attested by electrochemical impedance spectroscopy, electron paramagnetic resonance, and theoretical calculation. Such a phenomenon promoted obtaining an optimized electro/photocatalyst with exceptional activity, facilitating not just the ORR but also the photochemical water‐splitting reaction. Curiously, adjusting the Ag/Pd ratio also affected the ORR mechanism, which was switched from a 2‐electron to a 4‐electron after optimization. Finally, Ag38Pd62/SiO2, the catalyst with the best proportion, exhibited a remarkable hydrogen production rate of 1039.8 μmol/gcatalyst during 300 minutes of water splitting, surpassing the performance of the conventional Degussa TiO2 P25 catalyst.

Investigation of the Effect of Oxide Additives on the Band Gap and Photocatalytic Efficiency of TiO2 as a Fixed Film.

The effects of various additives (Y2O3, Ga2O3, and WO3) on photocatalytic degradation efficiency under UV light-emitting diodes (LEDs) and the optical properties of TiO2 Degussa P25 were investigated using ketoprofen and diclofenac, two non-steroidal anti-inflammatory drugs commonly detected in German rivers. Experimental results demonstrated that thin films containing these additives exhibited similar photocatalytic degradation efficiencies as pure TiO2, achieving a 30% degradation of ketoprofen over 150 min. In contrast, the Y2O3/TiO2 thin film showed significantly improved performance, achieving a 46% degradation of ketoprofen in 180 min. Notably, the Y2O3/TiO2 system was three times more effective in degrading diclofenac compared to pure TiO2. Additionally, the Y2O3/TiO2 photocatalyst retained its activity over three successive cycles with only a slight decrease in efficiency. The photocatalytic degradation of both organic pollutants followed first-order kinetics with all photocatalysts. The investigation included SEM imaging to assess the surface homogeneity of the thin films and UV-vis solid-state spectroscopy to evaluate the impact of the additives on the energy band gap of TiO2.

Sol–gel synthesis of iron titanates for the photocatalytic degradation of cyanide

Iron titanate mixed metal oxides were synthesized by the sol–gel method through four different routes. The effect of (i) the solvent of iron precursor, (ii) the addition of the chelating agent to the titanium or iron solution and (iii) the molar ratio between the chelating agent and the titanium or iron precursor over the overall percentage of obtained iron titanates was evaluated. Fourier-transform infrared spectroscopy (FTIR) and UV–Vis spectroscopy (UV–Vis) performed on the reaction medium evidenced the formation of acetate complexes of titanium (IV) or iron (III) during the different routes. X-ray diffraction (XRD) patterns of the obtained materials showed the formation of ilmenite (FeTiO3), pseudorutile (Fe2Ti3O9) and pseudobrookite (Fe2TiO5) in different proportions, as well as hematite (Fe2O3), rutile [TiO2 (R)] and anatase [TiO2 (A)]. The materials with the highest content of iron titanates obtained in each route were characterized and evaluated in the photocatalytic degradation of cyanide using visible light irradiation. UV–Vis Diffuse Reflectance Spectroscopy (UV–Vis DRS) showed that the samples exhibited energy bandgap values between 2.31 and 2.90 eV, which agrees with the values reported for iron titanates and evidence the possible activation of the materials under visible light. Scanning electron microscopy (SEM) and nitrogen physisorption results showed that the synthesized materials exhibited nanometric particle size and lower surface area (36.7 ± 4.8 m2·g-1) than TiO2 Degussa P-25 (72–155 m2·g-1). The photocatalytic performance of the synthesized materials toward oxidation of CN− exceeded by 56% the activity of pure TiO2. The content of iron titanates in the synthesized materials was found to be the variable with the greatest influence on the photodegradation of cyanide. In addition, an inversely proportional relationship between the pseudorutile content of the materials and their photocatalytic activity was observed.

Facile Preparation Method of TiO2/Activated Carbon for Photocatalytic Degradation of Methylene Blue.

The development of nanocomposite photocatalysts with high photocatalytic activity, cost-effectiveness, a simple preparation process, and scalability for practical applications is of great interest. In this study, nanocomposites of TiO2 Degussa P25 nanoparticles/activated carbon (TiO2/AC) were prepared at various mass ratios of (4:1), (3:2), (2:3), and (1:4) by a facile process involving manual mechanical pounding, ultrasonic-assisted mixing in an ethanol solution, paper filtration, and mild thermal annealing. The characterization methods included XRD, SEM-EDS, Raman, FTIR, XPS, and UV-Vis spectroscopies. The effects of TiO2/AC mass ratios on the structural, morphological, and photocatalytic properties were systematically studied in comparison with bare TiO2 and bare AC. TiO2 nanoparticles exhibited dominant anatase and minor rutile phases and a crystallite size of approximately 21 nm, while AC had XRD peaks of graphite and carbon and a crystallite size of 49 nm. The composites exhibited tight decoration of TiO2 nanoparticles on micron-/submicron AC particles, and uniform TiO2/AC composites were obtained, as evidenced by the uniform distribution of Ti, O, and C in an EDS mapping. Moreover, Raman spectra show the typical vibration modes of anatase TiO2 (e.g., E1g(1), B1g(1), Eg(3)) and carbon materials with D and G bands. The TiO2/AC with (4:1), (3:2), and (2:3) possessed higher reaction rate constants (k) in photocatalytic degradation of methylene blue (MB) than that of either TiO2 or AC. Among the investigated materials, TiO2/AC = 4:1 achieved the highest photocatalytic activity with a high k of 55.2 × 10-3 min-1 and an MB removal efficiency of 96.6% after 30 min of treatment under UV-Vis irradiation (120 mW/cm2). The enhanced photocatalytic activity for TiO2/AC is due to the synergistic effect of the high adsorption capability of AC and the high photocatalytic activity of TiO2. Furthermore, TiO2/AC promotes the separation of photoexcited electron/hole (e-/h+) pairs to reduce their recombination rate and thus enhance photocatalytic activity. The optimal TiO2/AC composite with a mass ratio of 4/1 is suggested for treating industrial or household wastewater with organic pollutants.

Ensuring Photocatalyst Properties on Cellulosic Fabric by Using Citric Acid Modified with TiO2 Degussa P25 Nanoparticles

Citric acid, which is a type of polycarboxylic acid, is environmentally friendly, and non-harmful and it can be used as a cross-linker. Titanium dioxide (TiO2) nanoparticle is a catalyst that provides many properties for textile products with its large surface area. Present study, a mixture was prepared with different concentrations of citric acid and commercial TiO2 Degussa P25 nanopowder suspensions. Two different curing temperatures (120°C and 140°C) were applied to the cotton fabrics in the pad-dry-cure method. The adhesion of the chemicals to the fiber surface was confirmed by scanning electron microscopy (SEM) and Fourier transform infrared spectrophotometer (FT/IR) analysis. The yellowing effect caused by citric acid on cotton fabrics was eliminated with white TiO2 nanoparticles. Methylene blue was used for staining the samples. Color analyses were performed with a spectrophotometer to determine photocatalytic properties of the samples. It was determined that the samples treated with a mixture of 30 g/L citric acid and TiO2 suspensions were the most discolored samples after exposure to solar light. The photocatalyst properties of the samples were further improved by removing the aggregation of TiO2 NPs on the fiber surface with the washing procedure.

Tailoring BiOBr Photocatalyst: In-situ Bi Doping for Enhanced Photocatalytic Removal of Sulfamethoxazole, SMX Antibiotic

There is a notable emphasis on the development of photocatalysts to degrade antibiotics, such as sulfamethoxazole (SMX), in aquatic environments due to their persistence and associated toxicological impacts. In this study, BiOBr photocatalysts were synthesized by incorporating in-situ Bi doping. Various Bi/BiOBr composites were produced through a hydrothermal method at varying temperatures and subsequently characterized using X-ray diffraction (XRD), UV-vis diffuse reflectance spectroscopy (UV-vis DRS), X-ray fluorescence (XRF), and nitrogen adsorption-desorption isotherm. The characterization data revealed that the Bi-metal began to emerge at a hydrothermal temperature of 180 °C (BB180) in the BiOBr-based semiconductor and completed its conversion to Bi-metal at a hydrothermal temperature of 270 °C (BB270). This transformation leads to the generation of Bi3+ in conjunction with oxygen vacancies, acting as active electron traps and enhancing the separation efficiency of light-induced electron-hole pairs. This results in a narrow band gap of Bi/BiOBr photocatalyst, increasing its sensitivity towards visible light. BB180 exhibited the highest photocatalytic rate in the degradation of SMX with a removal efficiency of 74.35% within 4 hours of reaction under Xenon lamp irradiation and an apparent rate constant of 6.5 x 10-3 min-1, surpassing the commercial TiO2 Degussa P25. This finding opens up a new pathway for the development of a catalyst responsive to visible light, specifically designed for the detoxification of antibiotics in wastewater.

Combination of ensemble machine learning models in photocatalytic studies using nano TiO2 - Lignin based biochar

Synergizing photocatalytic reactions with machine learning methods can effectively optimize and automate the remediation of pollutants. In this work, commercial Degussa TiO2 nanoparticles and lignin based biochar (LB) where used to prepare TiO2: lignin based biochar (TLB) composites using ultrasound-assisted co-precipitation method. The photocatalytic property of the TLB composites where studied by conducting the photocatalytic degradation of a Basic blue 41 (BB41) dye. The influence of calcination temperature, T:LB compositions, catalyst dosage, initial dye pH, initial dye concentration, and illumination time on photocatalytic dye degradation were experimentally studied. The degradation efficiency of 96.72 % was obtained under optimized conditions for the photocatalyst calcined at 500 °C containing a 1:1 wt percentage of TiO2 and LB. The experimental data was further used to predict the photocatalytic degradation efficiency using Gradient Tree Boosting (GTB) and Extra Trees (ET) models. The GTB model gave the highest prediction accuracy of 94 %. The permutation variable importance revealed catalyst dosage and dye concentration as the most influential parameters in the prediction of the photocatalytic dye degradation efficiency.

PHOTOCATALYTIC DEGRADATION OF 3-CHLOROPHENOL USING Pd/Ag DOPED ON P25 DEGUSSA TiO2 NANOPARTICLE WITH UV RADIATION

Photocatalytic degradation of 3-chlorophenol was investigated using Pd/Ag doped on P25 Degussa TiO2. The Pd/AgTiO2 photocatalysts were prepared by sol immobilization method. A fabricated photo-reactor was used in photocatalytic degradation of 3-chlorophenol and monitored using HPLC. The experimental results indicates that doping of Pd/Ag on TiO2 increases the photocatalytic efficiency of TiO2. The experimental results indicates that Pd/ TiO2 has a photodegradation efficiency of 40.44% while Ag/TiO2 has a photodegradation efficiency of 60.44%. The dried catalysts were subsequently used again under the same experimental condition with a fresh 3-chlorophenol up to four (4) times. The result indicates that the re-used catalysts remain active for up to four (4) times of usage with minor reduction in activity, which is attributed to metal leaching. Ag/TiO2 has higher rate constant of - 0.019 than Pd/TiO2 which is -0.031, the rate constant for the degradation followed first-order reaction kinetics. The photocatalytic degradation of 3-chlorophenol indicates unstable degradation due to effect of inductive and mesomeric effect which is less on meta-position. The use of nanotechnology in wastewater treatment plants to curtail the environmental and health consequences of a widespread of organic pollutants should be encouraged.

Facile and Simple Post Treatment Ball Milling Strategy for the Production of Low-Cost TiO2 Composites with Enhanced Photocatalytic Performance and Applicability to Construction Materials.

A facile and cost-effective approach assisted by ball milling (BM) of commercial titanium dioxide (TiO2), has been utilized to develop cheaper and efficient construction materials. At least three of the commercial and cheaper TiO2 samples (BA01-01, BA01-01+ and R996, designated as A1, A4 and R1, respectively) were selected and subjected to BM treatment to enhance their photocatalytic efficiencies, if possible. It was noted, that the samples A1, A4 and R1 were typical composites of TiO2 and calcium carbonate (CaCO3) and contained varying proportions of anatase, and rutile phases of TiO2 and CaCO3. Two of the highly efficient commercial TiO2 samples, Degussa P25 (simply designated as P25) and ST01 (Ishihara Ind.) were selected for making benchmark comparisons of photocatalytic efficiencies. The BM treated TiO2 samples (designated as TiO2-BM with respect to A1, A4 and R1) were evaluated for photocatalytic efficiencies both in both aqueous (methylene blue (MB)) and gaseous (NOx) photodegradation reactions. Based on detailed comparative investigations, it was observed that A1-BM photocatalyst exhibited superior photocatalytic performances over A4-BM and R1-BM, towards both MB and NOx photodegradation reactions. The difference of NOx photodegradation efficiency between the mortar mixed with A1-BM and that mixed with ST01, and P-25 at 15% were 16.6%, and 32.4%, respectively. Even though the mortar mixed with A1-BM at 15% composition exhibited a slightly lower NOx photodegradation efficiency as compared to mortar mixed with the expensive ST01 and P-25 photocatalysts, the present work promises an economic application in the eco-friendly construction materials for air purification considering the far lower cost of A1. The reasons for the superior performance of A1-BM were deduced through characterization of optical properties, surface characteristics, phase composition, morphology, microstructure and particle size distribution between pristine and BM treated A1 using characterization techniques such as diffuse reflectance spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction analysis, field emission scanning electron microscopy and particle size analysis.

Solar-driven photodegradation of synthetic dyes by ternary of titanium oxide-copper oxide-chitosan catalyst

The ternary titanium oxide (TiO2), copper oxide (CuO), and chitosan (TiO2/CuO/Chitosan) photocatalyst (composites) for the photodegradation of synthetic methyl orange (MO) were developed by entrapping copper ions and nanosized TiO2 into chitosan thin films at room temperature. TiO2 Degussa P25 was incorporated with CuO and Chitosan (CS) solution using an ex-situ synthesis method before being immobilized onto glass plates via a dip-coating technique. This study is the first time approach for a combination of a composite comprising two metal oxides to suppress the electron-hole recombination, thus enhancing their catalytic and adsorptive properties. The morphology and surface interactions of the TiO2/CuO/Chitosan composite were determined using techniques such as XRD, FTIR, RAMAN, and SEM-EDX, respectively. The results show the anatase phase and homogenous spherical features of TiO2. The TiO2/CuO/Chitosan composites (0.5 gL-1) exhibited excellent activity for the photodegradation of MO under solar irradiation (λ > 400 nm) at different pH. The decolorization efficiency increased according to pH 9 < pH 7 < pH 6 < pH 3 with the highest degradation efficiency of 85.29% at 1 ppm MO solution, reaching two times greater than the pristine TiO2 nanoparticles (56.55%). Complete degradation of MO was attained at 240 min of solar irradiation with pH 3 using the optimum TiO2/CuO/Chitosan composites of 1:4:1 composition (5 cycles of dip coating) and the photodegradation rate constant is 0.0073 min−1. The physic-chemical study has established the structure, crystalline phase, surface contact, and stability of the catalyst. The photocatalytic improvement under visible irradiation is attributed to band-gap reduction and suspension of electron-hole recombination of the ternary catalyst system. The results of this study offer guidelines for the design of a new synthetic strategy.for the preparation of an efficient photocatalyst for the selective oxidation of synthetic azo dyes compounds.

Photocatalytic degradation of organic micropollutants under UV-A and visible light irradiation by exfoliated g-C3N4 catalysts

In the present study, the photocatalytic performance of exfoliated graphitic carbon nitride (g-C3N4) catalysts, with enhanced properties and response in UV and visible light irradiation, was evaluated for the removal of selected contaminants i.e., diuron, bisphenol A and ethyl paraben. Commercial TiO2 Degussa P25 was also used as a reference photocatalyst. The g-C3N4 catalysts demonstrated good photocatalytic activity which in some cases is comparable to TiO2 Degussa P25 leading to high removal percentages of the studied micropollutants under UV-A light irradiation. In contrast to TiO2 Degussa P25, g-C3N4 catalysts were also able to degrade the studied micropollutants under visible light irradiation. For all the studied g-C3N4 catalysts under both UV-A and visible light irradiation, the overall degradation rate decreases in the order of bisphenol A > diuron > ethyl paraben. Among the studied g-C3N4, the chemically exfoliated catalyst (g-C3N4-CHEM) showed superior photocatalytic activity under UV-A light irradiation due to its enhanced characteristics, such as pore volume and specific surface area and ~ 82.0 % in 6 min, ~75.7 % in 15 min and ~ 96.3 % in 40 min removals were achieved for BPA, DIU and EP, respectively. Under visible light irradiation, the thermally exfoliated catalyst (g-C3N4-THERM) demonstrated the best photocatalytic performance and the degradation ranged from ~29.5 to 59.4 % after 120 min. EPR data revealed that the three g-C3N4 semiconductors generate mainly O2•−, whereas TiO2 Degussa P25 generates both HO• and O2•−, the latter only under UV-A light irradiation. Nevertheless, the indirect formation of HO• in the case of g-C3N4 should also be considered. Hydroxylation, oxidation, dealkylation, dechlorination and ring opening were the main degradation pathways. The process proceeded without significant alterations in toxicity levels. Based on the results, heterogeneous photocatalysis using g-C3N4 catalysts is a promising method for the removal of organic micropollutants without the formation of harmful transformation products.

Adsorption Isotherms for CBY 3G-P Dye Removal from Aqueous Media Using TiO&lt;sub&gt;2&lt;/sub&gt; Degussa, Fe&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;3&lt;/sub&gt;, and TiO&lt;sub&gt;2&lt;/sub&gt;/(DPC)

The adsorption of Cibacron Brilliant Yellow (CBY) 3-GP dye onto TiO2 Degussa, Fe2O3, and TiO2 anatase/Diphenylcarbizide in aqueous solution was studied with respect to temperature, contact time, and pH. The CBY 3-GP adsorption at equilibrium increased as the initial dye concentration increased for TiO2/DPC, while it decreased for TiO2 Degussa; however, it increased the initial dye concentration. The best removal efficiency was obtained at 1 mg for TiO2/DPC, TiO2 Degussa, and the amount of adsorption decreases with the rising of temperature. The negative ΔH° reveals the adsorption is exothermic and extremely negative ΔS° for TiO2 Degussa. The negative value for ΔS° indicates a regular increase of the randomness at the TiO2/DPC and Fe2O3 solution interface during adsorption. The intraparticle diffusion, pseudo-first- and second-order kinetic models were used. The Langmuir, Temkin, Freundlich, and Dubbin adsorption models were examined to describe the equilibrium isotherms. The usage of TiO2 Degussa and TiO2/DPC indicates that the equilibrium sorption was favorable.

Stable bidentate coordination sulfated TiO2 for highly durable photocatalytic degradation of gaseous acetone

Sulfated TiO2 was considered to be one of the most promising photocatalysts for enhancing photodegradation of organic pollutants. Different sulfate coordinated TiO2 catalysts were fabricated for photocatalytic degradation of acetone. The commercial Degussa TiO2 treated with concentrated H2SO4 showed a great improvement of acetone removal of 85% at continuous flow reaction and no deactivation occurred with prolonging reaction time, as comparison that parent TiO2 had a low removal rate and rapid deactivation for acetone degradation. Two kinds of SO42- coordination on TiO2 were revealed dependent on the treated H2SO4 concentration. Stable bidentate coordination SO42- acted as a trap center of photogenerated electrons for photocatalytic degradation of acetone. However, loose monodentate coordination SO42- on TiO2 surface was liable to open bridging S-OH-Ti group, resulting in the deactivation of photocatalytic acetone degradation. This work provided insight into the relationship between sulfate structure and its photocatalytic performance for sulfated TiO2 photocatalyst.

Ecotoxicity of TiO2, cerium and zirconium doped TiO2 photocatalysts prepared by different preparation methods and using different titanium precursors

Ecotoxicological effects of manufactured TiO2, cerium doped TiO2 and zirconium doped TiO2 prepared by different chemical methods and using different chemical precursors were evaluated, since these nanomaterials are keenly investigated semiconductor photocatalysts for waste and drinking water and waste gas purification in last three decades. Acute biological toxicity of manufactured photocatalysts was evaluated based on Sinapis alba seeds germination and Lemna minor fronds growth tests, and was compared to commercial photocatalyst TiO2 Degussa P25. Toxicity tests exhibited good sensitivity for monitoring of the toxicity of investigated nanomaterials. TiO2 toxicity results demonstrate that TiO2 prepared using titanyl sulphate as a Ti precursor are toxic to both plant species contrary to TiO2 prepared using titanium (IV) isopropoxide. Cerium doped TiO2 with Ce amount <5.5 wt.% proved to be non-toxic to both plant species and zirconium doped TiO2 even stimulates both plant species growth. Small crystallite-size and high surface area are not the toxicity-determining factors. In case of TiO2 prepared by using titanyl sulphate (TiO2-TH-C, TiO2-TH-PW), the chemical issues, i.e. the huge release of Ti4+ ions to nutrient aqueous solutions from TiO2 photocatalysts and the presence of SO42− onto TiO2 photocatalyst surfaces were identified. The presence of SO42− was identified as the chemical cause of TiO2 toxicity to both Lemna minor fronds and Sinapis alba seeds. High toxicity of Ce0.05Ti0.95On photocatalyst to Sinapis alba seeds was attributed to high content of cerium (∼9 wt.%) in TiO2 which led to formation of CeO2 of nuclei-size.

Study of phytotoxicity, remarkable photocatalytic activity, recycling process and energy consumption cost of TiO2 quantum dots photocatalyst for photodegradation of Coomassie brilliant blue R dye

The phytotoxicity experimental assessment revealed that the water used in the germination of Lycopersicon esculentum tomato seeds which was treated with TiO2 quantum dots, TDs1 (2.7 nm), TDs2 (3.1 nm) and TiO2 (Degussa) respectively, had no impact on the germination process. TiO2 quantum dots with a high BET Specific surface area of 462.3 m2/g for TDs1 (2.7 nm) and 338.22 m2/g for TDs2 (3.1 nm) were synthesized through the sol-gel method using TiCl4 in different polar solvents. The structure, shape, and size of the prepared TDs samples have been characterized by techniques such as XRD, FE-SEM, HRTEM, and EDX, confirming no additional phases or impurities in TDs. The optical band gaps of TDs samples were determined from their diffuse reflectance spectral data using Kubelka-Munk Equation. Photocatalytic activities of 91 and 89% were achieved in the mineralization of Coomassie brilliant blue R (CBBR), a model commercial dye, under direct sunlight and xenon lamp irradiation, respectively. The reactive species on the photodegradation mechanism for the TDs prepared samples were determined by different trapping agents. The photocatalytic activity of the TDs samples remained strong after eight repetitions with a Xenon photoreactor and direct solar light. The assessment of the photodegradation efficiency of CBBR dye in terms of its beneficial influence on energy consumption (EE/O) and price estimates has been reported.

Görünür-Işık ile Çalışan Fotokatalizör Hematitin Çinko ve Bakır ile Katkılanmasıyla Geliştirilmesinin Karşılaştırmalı İncelenmesi

The low cost, earth abundance, nontoxic, and efficient photocatalysts materials have a critical role in order to solve environmental issues. In this regard, hematite (α-Fe2O3) has received significant attention due to its desirable properties. In the present study, zinc-doped and copper-doped hematite nanoparticles were synthesized by the hydrothermal method. The photocatalytic features of produced nanopowders were investigated. The evaluations of photocatalytic activities of synthesized nanoparticles were executed by monitoring the degradation rate of Rhodamine B (RhB) under the solar simulator in heterogeneous photocatalysis. Compared to commercial Degussa TiO2 powder, the transition metal doped hematite (α-Fe2O3) samples showed better photocatalytic activities against RhB under the solar simulator. It was observed that even though there were no significant differences in their characteristic properties strongly affecting photocatalytic activity such as morphological features, optical absorption characteristics, and band gaps, Cu-doped α-Fe2O3 nanoparticles exhibited higher photocatalytic activity, which is %20 higher than the Zn-doped α-Fe2O3. The synthesized Cu-doped hematite nanoparticles are hopeful materials as a visible-light-driven photocatalytic material to degrade organic pollutants in aquatic media.

Easy way to produce iron-doped titania nanoparticles via the solid-state method and investigation their photocatalytic activity

This study focuses on the synthesis of iron-doped TiO2 nanoparticles “via solid-state” method, as an alternative to the more common doping strategies, with different iron content (0.5, 1.0, 1.5, and 2.0 wt%) using commercial titania Degussa P25 and TiO2 synthesized (sTiO2) via microemulsion method. The samples were characterized by SEM, BET, UV–Vis-DRS, and XRD. The photocatalytic activity was evaluated in terms of methylene blue (MB) degradation in aqueous solution under visible radiation (LED lamp 13 W) and under different conditions (pH, catalyst dosage, pollutant initial concentration, irradiance). The tests showed a big difference between sTiO2 and Degussa 25. The sTiO2 with an iron load of 1.0 wt% (1% Fe–TiO2) has been proven to be the best photocatalyst. This behavior is attributed to the Fe3+ species in sTiO2 crystal lattice whose presence decreases the bandgap.Graphical abstract

The Influence of Synthesized TiO2-Nanoparticles on the Performance of Inks Utilized in Printing Documents

Titanium dioxide is also called titania and occurs in nature in anatase and rutile forms. It is widely used as a white pigment, catalyst support, and photocatalyst. Nano-TiO2 pigments in pure crystallographic anatase phases have been successfully synthesized via sol-gel method. Nano-TiO2 material has been characterized by various techniques such as XRD, TEM, and XPS. The prepared nano-TiO2 was mixed with two different offset inks (falcon and jobbing) to upgrade the physical and optical properties of the offset inks and compared with Degussa TiO2 before and after the application was tracking and measured. Generally, requiring a small amount of modification is better to avoid any ink malfunction, nano ink requires 0.1 % is because of the photoactive anatase structure of TiO2, while Degussa requires 1 % because it has a 15% rutile structure, which considered a photoinactive phase structure of TiO2.

TiO2 quantum dots: Energy consumption cost,germination, and phytotoxicity studies, recycling photo and solar catalytic processes of reactive yellow 145 dye and natural industrial wastewater

The germination of Lycopersicon esculentum tomato seeds that had been planted with water containing TiO2QDs1(2.9 nm), TiO2QDs2 (3.2 nm), and TiO2 (Degussa) without no phytotoxicity effect on the germination process. TiO2QDs1 (2.9 nm) and TiO2QDs2 (3.2) were successfully synthesized at low calcination temperatures: 280 and 310 0C for 180 min, respectively, using the sol–gel process. The synthesized TiO2QDs1(2.9 nm) and TiO2QDs2 (3.2 nm) were characterized by: XRD, FE-SEM, HRTEM, and EDX to analyze the structure, shape, and size of the generated TiO2QDs samples. The photocatalytic activities of the TiO2QDs in the photodegradation of Reactive yellow 145 dye as a commercial dye and actual industrial wastewater samples using both a Xenon lamp light irradiation source and direct sunlight were assessed. They showed highly photocatalytic performances recorded at 85 to 90 percent, and the photodegradation rate was still distinguishable till ten repetition times for the photodegradation process of the reactive yellow 145 dye and till six repetition times for the natural industrial wastewater samples used in this study. Also, an analysis of the photodegradation efficiency of the Reactive yellow 145 dye has been done in terms of the positive effect on the energy consumption ratio (EE/O) as pricing estimations.

Deep-learning framework for fully-automated recognition of TiO2 polymorphs based on Raman spectroscopy

Emerging machine learning techniques can be applied to Raman spectroscopy measurements for the identification of minerals. In this project, we describe a deep learning-based solution for automatic identification of complex polymorph structures from their Raman signatures. We propose a new framework using Convolutional Neural Networks and Long Short-Term Memory networks for compound identification. We train and evaluate our model using the publicly-available RRUFF spectral database. For model validation purposes, we synthesized and identified different TiO2 polymorphs to evaluate the performance and accuracy of the proposed framework. TiO2 is a ubiquitous material playing a crucial role in many industrial applications. Its unique properties are currently used advantageously in several research and industrial fields including energy storage, surface modifications, optical elements, electrical insulation to microelectronic devices such as logic gates and memristors. The results show that our model correctly identifies pure Anatase and Rutile with a high degree of confidence. Moreover, it can also identify defect-rich Anatase and modified Rutile based on their modified Raman Spectra. The model can also correctly identify the key component, Anatase, from the P25 Degussa TiO2. Based on the initial results, we firmly believe that implementing this model for automatically detecting complex polymorph structures will significantly increase the throughput, while dramatically reducing costs.