Probing of photocatalytic surface sites on SO42−/TiO2 solid acids by in situ FT-IR spectroscopy and pyridine adsorption

Lewis and Brønsted Acids Synergy in Photocatalytic Aerobic Alcohol Oxidations

Photocatalytic chemical transformations for green organic synthesis has attracted much interest. However, their development is greatly hampered by the lack of sufficient reactive sites on the photocatalyst surface for the adsorption and activation of substrate molecules. Herein, we demonstrate that the introduction of well-defined Lewis and Brønsted acid sites coexisting on the surface of TiO2 (SO4 2-/N-TiO2) creates abundant active adsorption sites for photoredox reactions. The electron-deficient Lewis acid sites supply coordinatively unsaturated surface sites to adsorb molecular oxygen, and the Brønsted acid sites are liable to donate protons to form hydrogen bonds with the OH groups of alcohols like benzyl alcohol (BA). These coexistent acid sites result in a strong synergistic effect in photocatalytic aerobic oxidation of BA. For example, the conversion of BA to benzaldehyde was found to be 88.6 %, being much higher than those of pristine TiO2 (14.7 %), N-doped TiO2 (N-TiO2, 24.6 %), sulfated TiO2 (SO4 2-/ TiO2, 35.4 %), and even their sum. The apparent quantum efficiency (AQE) was determined to be 58.1 % at 365 nm and 12.9 % at 420 nm over SO4 2-/N-TiO2. This strategy to create effective synergistic Lewis and Brønsted acids on the catalyst surfaces enables us to apply it to other semiconducting photocatalytic organic transformations.

Regulating Carbon Vacancies and Undercoordinated Mo Sites in Mo2C Catalysts Toward Photo-Thermal Catalytic Conversion of Biomass Into H2 Fuel

The conversion of biomass into chemical fuels is exciting but quite challenging in the development of an effective conversion strategy to generate easily-separated products without energy consumption. Herein, a lignocellulosic biomass-to-H2 conversion system via photo-thermal catalysis over Mo2C hierarchical nanotube catalysts in an acidic solution, in which the lignocellulose is hydrolyzed to small organic molecules (such as glucose, etc) by dilute H2SO4, and then the resulting glucose is oxidized by Mo2C catalyst to generate H2 are reported. During the photo-thermal catalytic processes, the carbon vacancy in Mo2C catalysts results in the generation of undercoordinated Mo sites, which act as active sites for both biomass oxidation and H2 generation reactions. Thus, the successful photo-thermal catalytic conversion of common agricultural and forestry biomass including polar wood chip, bamboo, wheat straw, rice straw, corncob, and rice hull into H2 fuel is realized, and the highest H2 generation rate achieves 30 µmol g-1 h-1 in the wheat straw system. Outwork affords efficient noble-metal-free catalysts with adjustable active sites for photo-thermal catalytic conversion of lignocellulosic biomass into H2.

Glycerol Oligomerization over Titania-Based Catalyst Compositions

The possibility of using TiO2 -based compositions: individual and sulfated titania, and their composites with carbon nanotubes as catalysts for glycerol oligomerization has been displayed. The effect of modification of TiO2 with sulfur and carbon nanotubes on acid-base and catalytic characteristics in the glycerol conversion was investigated. The activation of glycerol on the catalysts has been studied using attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy. Only the samples based on sulfated titania are active over glycerol transformation, showing up to 58.7 % conversion. This is explained by the presence of strong base sites. Glycerides up to pentaglycerides, both linear and nonlinear structure are formed by glycerol oligomerization over TiO2 -S. The addition of nanotubes to the catalyst reduces both the glycerol conversion (up to 10.5 %) and the yield of glycerides. However, the spectrum of the resulting products is significantly narrowed, increasing the selectivity for short-chain glycerides: the portion of diglycerides reaches 72 %, and triglycerides 21 %. Herewith, glycerides of a linear structure only formed.

LDPE cracking over mono- and divalent metal-doped beta zeolites

This study evaluates the effect of loading various mono and divalent metals in Beta zeolite on low-density polyethylene (LDPE) cracking. We revealed that Tl and Ba ions enhanced Lewis acidity, leading to higher catalytic activity on LDPE cracking.

ATR FTIR Study of the Interaction of TiO2 Nanoparticle Films with β-Lactoglobulin and Bile Salts

The technique of in situ particle film attenuated total reflection Fourier transform infrared spectroscopy (ATR FTIR) has been used to probe the adsorption and coadsorption (sequential) of a common food protein (β-lactoglobulin, BLG) and two representative bile salts (taurocholic acid and glycocholic acid, abbreviated as TCA and GCA) onto the surface of titanium dioxide (TiO₂) nanoparticles. Evaluating of binding interactions between commonly used (historically now, in some countries) food additives and food components, as well as the body's own digestion chemicals, is a critical step in understanding the role of colloidal phenomena in digestion and bioavailability. TCA is found to adsorb onto TiO₂ but without any significant ability to be retained when it is not present in the aqueous phase. GCA is also found to adsorb via two distinct binding mechanisms, with one type of adsorbed species being resistant to removal. BLG adsorbs, is irreversibly bound, and has altered conformation when adsorbed at pH 2 (stomach conditions) to the conformation when adsorbed at pH 6.5 (small intestine conditions). This altered conformation is not interface-dependent and is mirrored in the solution spectra of BLG. Sequential coadsorption studies indicate that TCA and GCA adsorb onto TiO₂ nanoparticle surfaces and display similar degrees of reversibility and binding in the presence or absence of preadsorbed BLG.

Self-wetting triphase photocatalysis for effective and selective removal of hydrophilic volatile organic compounds in air

Photocatalytic air purification is widely regarded as a promising technology, but it calls for more efficient photocatalytic materials and systems. Here we report a strategy to introduce an in-situ water (self-wetting) layer on WO3 by coating hygroscopic periodic acid (PA) to dramatically enhance the photocatalytic removal of hydrophilic volatile organic compounds (VOCs) in air. In ambient air, water vapor is condensed on WO3 to make a unique tri-phasic (air/water/WO3) system. The in-situ formed water layer selectively concentrates hydrophilic VOCs. PA plays the multiple roles as a water-layer inducer, a surface-complexing ligand enhancing visible light absorption, and a strong electron acceptor. Under visible light, the photogenerated electrons are rapidly scavenged by periodate to produce more •OH. PA/WO3 exhibits excellent photocatalytic activity for acetaldehyde degradation with an apparent quantum efficiency of 64.3% at 460 nm, which is the highest value ever reported. Other hydrophilic VOCs like formaldehyde that are readily dissolved into the in-situ water layer on WO3 are also rapidly degraded, whereas hydrophobic VOCs remain intact during photocatalysis due to the "water barrier effect". PA/WO3 successfully demonstrated an excellent capacity for degrading hydrophilic VOCs selectively in wide-range concentrations (0.5-700 ppmv).

In situ construction of sulfated TiO2 nanoparticles with TiOSO4 for enhanced photocatalytic hydrogen production

Photocatalytic hydrogen production from water is a promising method to obtain clean energy in the future. In this work, the sulfated TiO2 photocatalyst is successfully constructed in situ via a soft-templated method for photocatalytic water splitting to produce hydrogen. The content of sulfate species in TiO2 can be tuned by changing the amount of the surfactant. The photocatalyst with the appropriate content of sulfate ions exhibits an apparent quantum efficiency (AQE) of 3.9% at 365 nm and a high hydrogen production rate of 24.32 mmol h-1 g-1, which is 1.65 times that of commercial TiO2 (P25). The optimized photocatalyst has excellent photocatalytic activity for hydrogen evolution benefitting from the presence of sulfate ions on the surface of TiO2, large surface area and oxygen vacancies, which facilitates the rapid migration of photo-generated electrons to its surface and the improvement of the separation efficiency of photo-generated carriers. This work may inspire the rational design and the development of high-efficiency photocatalysts.

Photocatalytic degradation of industrial acrylonitrile wastewater by F-S-Bi-TiO2 catalyst of ultrafine nanoparticles dispersed with SiO2 under natural sunlight

Highly active photocatalyst, having certain anti-ionic interfering function, of F, S and Bi doped TiO2/SiO2 was used for the first time to degrade the organic pollutants in acrylonitrile industrial wastewater under natural sunlight. The photocatalyst were prepared and characterized by UV-Vis, XRD, TEM, EDS, Nitrogen physical adsorption and XPS technique. UV-Vis analysis revealed addition of F, S and Bi into the lattice of TiO2 led to the expansion of TiO2 response in the visible region and hence the efficient separation of charge carrier. The photocatalytic potential of as prepared catalyst to degrade acrylonitrile wastewater under simulated and natural sunlight irradiation was investigated. The extent of degradation of acrylonitrile wastewater was evaluated by chemical oxygen demand (CODCr). CODCr in wastewater decreased from 88.36 to 7.20 mgL-1 via 14 h irradiation of simulated sunlight and achieved regulation discharge by 6 h under natural sunlight, illuminating our photocatalyst effectiveness for refractory industrial wastewater treatment. From TEM results, we found that SiO2 could disperse the photocatalyst with different component distributions between the surface and the bulk phase that should also be responsible for the light absorption and excellent photocatalytic performance. The XPS analysis confirmed the presence of surface hydroxyl group, oxygen vacancies.

Efficient photocatalytic degradation of acrylonitrile by Sulfur-Bismuth co-doped F-TiO2/SiO2 nanopowder

In this study, a simple sol-gel method was applied for preparing effectual photocatalyst of S-Bi co-doped F-TiO₂/SiO₂ (S-Bi-F-TiO₂/SiO₂) nanopowder. Optimal preparation conditions were obtained by optimizing the calcination temperature and the ratio of S and Bi. The synthesized powder was characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), energy dispersive spectrometer (EDS), X-ray photoelectron spectroscopy (XPS), brunauer-emmett-teller (BET), UV-Visible diffuse-reflectance spectroscopy (UV-Vis DRS), photoluminescence spectroscopy (PL) and ammonia adsorption and temperature-programmed desorption (NH₃-TPD). The photocatalytic activity was evaluated by the degradation of acrylonitrile under simulated visible light irradiation. S-Bi-F-TiO₂/SiO₂ nanopowder possess excellent photocatalytic properties under visible light for the degradation of acrylonitrile, when the calcination temperature was 450 °C for 2 h and the ratio of S and Bi was 0.02: 0.007. The degradation efficiency of acrylonitrile reached to 81.9% within 6 min of visible light irradiation. Compared with F-TiO₂/SiO₂ sample, NH₃-TPD and PL results revealed the higher photocatalytic activity for S-Bi-F-TiO₂/SiO₂, which is mainly due to the increase strength and number of surface acid site with S doping. The co-doping with S & Bi improved the separation of electron-hole pairs and enhanced the photocatalytic oxidizing species. The UV-Vis DRS showed stronger absorption in S-Bi co-doped F-TiO₂/SiO₂ catalyst as compared to F-TiO₂/SiO₂ catalyst. XPS results demonstrated the presence of various surface species viz. oxygen vacancies, Ti³⁺, Ti⁴⁺, O^2- and OH group.

Adsorption and photocatalytic degradation of benzene compounds on acidic F-TiO2/SiO2 catalyst

The adsorption and photocatalytic degradation performance of F-TiO₂/SiO₂ catalyst towards a series of benzene compounds were studied. The results revealed that the F-TiO₂/SiO₂ catalyst is superior to TiO₂ P25 in adsorption capacity and photocatalytic degradation under simulant sunlight irradiation. The adsorptive capacity for chlorobenzene is the highest and the degradation rate is the greatest among these target pollutants. The increase of absorptive organic molecules on acidic F-TiO₂/SiO₂ catalyst benefits photocatalytic degradation. The photocatalytic reaction accords to Langmuir-Hinshelwood mechanism. The FTIR results indicated that the promoting effect of acidic centers on adsorption of benzene compounds depends on electron property of the functional groups. The electron-donating groups (-OH and -NH₂) of benzene compounds are weakly adsorbed on acidic centers of the catalyst due to the competitive adsorption with H₂O, while the electron-withdrawing groups (-Cl and -NO₂) are adsorbed more strongly at acidic sites. The monosubstituted chlorobenzene prefers to perpendicular adsorption on acidic surface, while the disubstituted benzenes prefer to horizontal adsorption, which decreases the adsorbed amounts. A photocatalytic rate mainly depends on electron donating property of the functional group and amount of adsorptive organic molecules, but not on electron density of benzene ring.

Synergetic effects of defects and acid sites of 2D-ZnO photocatalysts on the photocatalytic performance

Regulation of defects and surface acidic sites of photocatalysts is an efficient approach to improve the photocatalytic activity. Ultrathin 2D-ZnO photocatalysts were prepared to uncover the synergetic effects of defects and surface acidic sites on the photocatalytic activity. The reaction constant for photocatalytic degradation of MB upon ZnO-S is 2.26, 2.82, 12.2 times higher than that of SH-500, SO-500, and ZnO-R, respectively. The results revealed that the surface defects, hydroxyl group and chemisorbed water played pivotal roles in the generation of reactive oxygen species (ROS). Although the limited improvement of visible absorption was achieved after introduction of oxygen vacancy (V_O), the overall photocatalytic activity decreased due to the reduced ROS production capacity shown by density functional theory (DFT) calculations. Hydroxyl radical is the key ROS in degradation of organics, and electron contributes a little bigger than hole in the generation of hydroxyl radical. Importantly, the decrease in surface acidic sites resulted in the decreased photocatalytic activity, proven by the dynamics of photoinduced carriers. This study reveals that the improved photocatalytic activity of 2D-ZnO photocatalysts can be attributed to the synergetic effects of surface defects and acidic sites rather than the enhanced visible absorption resulted from the V_O introduction.

Improved adsorption and degradation performance by S-doping of (001)-TiO2

In this work, sulfur-doped (S-doped) TiO₂ with the (001) face exposed was synthesized by thermal chemical vapor deposition at 180 or 250 °C using S/Ti molar ratios R _S/Ti of 0, 0.5, 1, 2, 3, 4 and 5. The S-doped samples synthesized at 250 °C exhibit a significantly improved photocatalytic performance. More precisely, S-doping has the following effects on the material: (1) S can adopt different chemical states in the samples. Specifically, it exists in the form of S^2- replacing O^2- at a ratio of R _S/Ti = 1 and also in the form of S⁶⁺ replacing Ti⁴⁺ at R _S/Ti ≥ 2. As a result, S-doping causes a lattice distortion, because the ionic radii of S^2- and S⁶⁺ differ from that of the O^2- and Ti⁴⁺ ions. (2) S-doping increases the adsorption coefficient A _e for methylene blue (MB) from 0.9% to 68.5% due to the synergistic effects of the oxygen vacancies, increased number of surface chemical adsorption centers as a result of SO₄ ^2- adsorption on the TiO₂ surface and the larger pore size. (3) S-doping increases the MB degradation rate from 6.9 × 10^-2 min^-1 to 18.2 × 10^-2 min^-1 due to an increase in the amount of •OH and •O^2- radicals.

Synthesis of core–shell N-TiO2@CuOx with enhanced visible light photocatalytic performance

In this paper, a core–shell N-TiO₂@CuO_x nanomaterial with increased visible light photocatalytic activity was successfully synthesized using a simple method. By synthesizing ammonium titanyl oxalate as a precursor, N-doped TiO₂ can be prepared, then the core–shell structure of N-TiO₂@CuO_x with a catalyst loading of Cu on its surface was prepared using a precipitation method. It was characterized in detail using XRD, TEM, BET, XPS and H₂-TPR, while its photocatalytic activity was evaluated using the probe reaction of the degradation of methyl orange. We found that the core–shell N-TiO₂@CuO_x nanomaterial can lessen the TiO₂ energy band-gap width due to the N-doping, as well as remarkably improving the photo-degradation activity due to a certain loading of Cu on the surfaces of N-TiO₂ supports. Therefore, a preparation method for a novel N, Cu co-doped TiO₂ photocatalyst with a core–shell structure and efficient photocatalytic performance has been provided.

In this paper, a core–shell N-TiO₂@CuO_x nanomaterial with increased visible light photocatalytic activity was successfully synthesized using a simple method.

Mapping surface-modified titania nanoparticles with implications for activity and facet control

The use of surface-directing species and surface additives to alter nanoparticle morphology and physicochemical properties of particular exposed facets has recently been attracting significant attention. However, challenges in their chemical analysis, sometimes at trace levels, and understanding their roles to elucidate surface structure–activity relationships in optical (solar cells) or (photo)catalytic performance and their removal are significant issues that remain to be solved. Here, we show a detailed analysis of TiO₂ facets promoted with surface species (OH, O, SO₄, F) with and without post-treatments by ³¹P adsorbate nuclear magnetic resonance, supported by a range of other characterization tools. We demonstrate that quantitative evaluations of the electronic and structural effects imposed by these surface additives and their removal mechanisms can be obtained, which may lead to the rational control of active TiO₂ (001) and (101) facets for a range of applications.

Metal oxide nanocrystals can be grown with different facets exposed to give variations in reactivity, but the chemical state of these surfaces is not clear. Here, the authors make use of a phosphine probe molecule allowing the differences in surface chemistry to be mapped by NMR spectroscopy.

Nano-12-Tungstophosporic Acid Cesium Salt Synthesized by Ultrasound as Catalyst for Alkylation of Benzene with dec-1-ene

Nano 12-tungtophosphoric acid cesium salt (Cs-TPA) was synthesized under ultrasonic irradiation in nanoscale. The obtained catalyst was characterized by various methods. These analyzes indicate that the chemical structure and crystallinity of nano Cs-TPA remained unchanged while its morphology was found to be different from traditional Cs-TPA which is in irregular shape, becoming spherical with an average particle size of about 50 nm.

Nano Cs-TPA was examined in the alkylation of benzene with dec-1-ene, its catalytic activity was remarkably enhanced compared to its original state. The catalyst reusability experiment also showed that the activity of nano Cs-TPA does not decrease even after five reused cycles.

Self-assembly of mesoporous Bi-S-TiO2 composites for degradation of industrial dinitrotoluene solution under UV light

Mesoporous Bi-S-TiO₂ composites were synthesized by the method combining evaporation-induced self-assembly (EISA) method with impregnation process. Characterization shows mesoporous Bi-S-TiO₂ was a highly crystalline anatase, with relatively high thermal stability, large surface area (75-120 m²/g), and large mesopore (10-20 nm). The results also revealed that Bi and S species existed in Bi⁴⁺, S^2-, S and S⁶⁺ forms in the mesoporous TiO₂, which allow the mesoporous Bi-S-TiO₂ illustrating strong absorption in the ultraviolet region, and the absorption edge shifts to the visible-light region. Photodegradation tests shown that, about 92.3% industrial aqueous dinitrotoluene (DNT) solution could be degraded by 1.5%Bi-S-TiO₂ under UV irradiation for 5 h. Concentration of Bi ions and calcination temperature were found to play important roles in its mesoporous properties and photocatalytic activity.

Catalytic transfer hydrogenation of levulinic acid to γ-valerolactone over a bifunctional tin catalyst

Efficient conversion of levulinic acid to γ-valerolactone over a bifunctional Sn catalyst under catalytic transfer hydrogenation.

Efficiency of Polymeric Membrane Graphene Oxide-TiO2for Removal of Azo Dye

Achieving the desired standard of drinking water quality has been one of the concerns across water treatment plants in the developing countries. Processes such as grid chamber, coagulation, sedimentation, clarification, filtration, and disinfection are typically used in water purification plants. Among these methods, unit filtration which employs polymers is one of the new technologies. There have been many studies about the use of semiconductive TiO2with graphene oxide (GO) on the base of different polymeric membranes for the removal of azo dyes, especially methylene blue (MB). Polymeric GO-TiO2membranes have high photocatalytic, antifouling property and permeate the flux removal of organic pollutants. The aim of this study was to investigate the characteristics of different polymeric membranes such as anionic perfluorinated polymer (Nafion), cellulose acetate, polycarbonate (PC), polysulfone fluoride (PSF), and polyvinylidene fluoride (PVDF). The result of this study showed that the GO-TiO2membrane can be used in the field of water treatment and will be used for the removal of polycyclic aromatic hydrocarbons (PAHs) from wastewater.

SOx Tolerant Pt/TiO2 Catalysts for CO Oxidation and the Effect of TiO2 Supports on Catalytic Activity

We developed a new technique for mitigating catalyst deactivation caused by SO2 in exhaust gases. A series of 0.1 wt %-Pt/TiO2 catalysts with different surface, crystal, and pore structures were prepared and tested for CO oxidation activity in the presence of SO2 and H2O. The order of the CO oxidation activity under the influence of SO2 was much different from that in the absence of SO2. Catalysts with a high ratio of larger pores exhibited higher catalytic activity under the influence of SO2 and H2O in the temperature range of 250-300 °C, whereas other parameters, such as BET surface area and crystal structure of the TiO2 support, had minor effects on the CO oxidation activity. The oxidation state of Pt differed significantly depending on the kind of TiO2 support. Some catalysts were less active without H2 reduction pretreatment due to the presence of oxidized Pt species.

Efficient biodiesel production via solid superacid catalysis: a critical review on recent breakthrough

Biodiesel produced from triglycerides and/or free fatty acids (FFAs) by transesterification and esterification has attracted immense attention during the past decades as a biodegradable, renewable and sustainable fuel.

Steam treatment of a hollow lithium phosphate catalyst: enhancing carbon deposition resistance and improving the catalytic performance of propylene oxide rearrangement

The reaction mechanism of propylene oxide rearrangement on a hollow lithium phosphate catalyst in the presence of steam.

Simple synthesis of lithium-doped sulfated titania nanoparticles and their high visible light photocatalytic activity under negative bias electrostatic field

Li-doped TiO₂/SO₄²⁻ nanoparticles were successfully synthesized via a simple calcinination process in a vacuum environment using Ti(SO₄)₂ and LiBr as precursors, and were characterised by TEM, XRD, IR, DLS, XPS and UV-vis (DRS).

Gold nanoparticles supported on layered TiO2–RGO hybrid as an enhanced and recyclable catalyst for microwave-assisted hydration reaction

A novel composite (Au–SO₄²⁻/TiO₂–RGO) is synthesized and serves as an enhanced catalyst for alkyne hydration.

Study of phosphate removal from aqueous solution by zinc oxide

Zinc oxide (ZnO) was synthesized and used to investigate the mechanism of phosphate removal from aqueous solution. ZnO particles were characterized by X-ray diffraction, scanning electron microscope and Fourier transform infrared spectroscopy before and after adsorption. Batch experiments were carried out to investigate the kinetics, isotherms, effects of initial pH and co-existing anions. The adsorption process was rapid and equilibrium was almost reached within 150 min. The adsorption kinetics were described well by a pseudo-second-order equation, and the maximum phosphate adsorption capacity was 163.4 mg/g at 298 K and pH ∼6.2±0.1. Thermodynamic analysis indicated the phosphate adsorption onto ZnO was endothermic and spontaneous. The point of zero charge of ZnO was around 8.4 according to the pH-drift method. Phosphate adsorption capacity reduced with the increasing initial solution pH values. The ligand exchange and Lewis acid-base interaction dominated the adsorption process in the lower and the higher pH range, respectively. Nitrate, sulfate and chloride ions had a negligible effect on phosphate removal, while carbonate displayed significant inhibition behavior.

Photocatalytic decomposition of acrylonitrile with N-F codoped TiO2/SiO2 under simulant solar light irradiation

The solid acid catalyst, N-F codoped TiO2/SiO2 composite oxide was prepared by a sol-gel method using NH4F as nitrogen and fluorine source. The prepared materials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), UV-Visible diffuse reflectance spectroscopy (UV-Vis), ammonia adsorption and temperature-programmed desorption (NH3-TPD), in situ Fourier transform infrared spectroscopy (FT-IR) and N2 physical adsorption isotherm. The photocatalytic activity of the catalyst for acrylonitrile degradation was investigated under simulant solar irradiation. The results showed that strong Lewis and Brønsted acid sites appear on the surface of the sample after N-F doping. Systematic investigation showed that the highest photocatalytic activity for acrylonitrile degradation was obtained for samples calcined at 450°C with molar ratio (NH4F to Ti) of 0.8. The degradation ratio of 71.5% was achieved with the prepared catalyst after 6-min irradiation, demonstrating the effectiveness of photocatalytic degradation of acrylonitrile with N-F codoped TiO2/SiO2 composite oxide. The photocatalyst is promising for application under solar light irradiation. Moreover, the intermediates generated after irradiation were verified by gas chromatography-mass spectrometry (GC-MS) analysis and UV-Vis spectroscopy to be simple organic acids with lower toxicity, and the degradation pathway was also proposed for acrylonitrile degradation with the prepared catalyst.

A facile solution-based approach to a photocatalytic active branched one-dimensional TiO2 array

Branched one-dimensional TiO₂ array with enhanced photocatalytic activity was fabricated via a facile solution-based strategy.

Mechanism for catalytic ozonation of p-nitrophenol in water with titanate nanotube supported manganese oxide

A support with acid sites favored the adsorption of ozone, while the supported MnO_x accelerated the decomposition of ozone into hydroxyl radicals for the mineralization of organic pollutants.