Comparative Photocatalytic Activity Research Articles

Enhanced photocatalytic degradation of antiviral drugs lopinavir and ritonavir by Ni doped ZnO/SiO2 nanocomposites

A series of silica-based Ni doped ZnO nanocomposites were successfully synthesized by the co-precipitation of zinc and nickel acetate salts in the presence of urea on the surface of amorphous silica using thermo-oxidative degradation at 600 °C with a concentration of 3, 6 and 9 mmol ZnO per 1 g SiO2. The effects of the dopants and SiO2 matrix on the structure, morphology and optical properties of the composites were investigated using N2 adsorption-desorption, Raman, XRD, UV-Vis, PL, FT-IR, SEM, and TEM analyses. XRD indicated the formation of a hexagonal ZnO wurtzite structure, while Ni2+ ions substituted Zn2+ sites in the host lattice. The size of nanoparticles was in the range of 10–100 nm and showed a broad fluorescence emission at 442–433 nm. The specific surface area was 110–171 m2 g−1. The materials showed high efficiency in removing the antiviral SARS-CoV-2 drugs lopinavir (LOPI) and ritonavir (RITO) from water. The comparative photocatalytic activity showed 100 % removal of LOPI by 3-, 6- and 9-Ni-ZnO/SiO2 photocatalysts after 60, 30 and 45 min of ultraviolet light irradiation, respectively, and 60 min for RITO for all catalyst samples. The effects of inorganic ions, dissolved organics and reusability on photocatalytic degradation were also described in terms of practical applications.

Enhanced Photocatalytic Hydrogen Production Activity Driven by TiO2/(MoP/CdS): Insights from Powder Particles to Thin Films.

Transitioning from powder photocatalysts to thin film photocatalysts is one of the necessary steps toward industrializing photocatalytic hydrogen production. Herein, we reported the integration of non-noble metal cocatalyst MoP decorated with TiO2 and CdS, forming TiO2/(MoP/CdS) for ultraviolet-visible light utilization. The designed powder TiO2/(MoP/CdS) composites achieved a superior hydrogen production rate of 42.2 mmol g-1 h-1, which is 30.1 times that of TiO2/CdS, performing the highest activity among the TiO2-CdS-based composite photocatalysts. Moreover, we fabricated a thin film from TiO2/(MoP/CdS) powder, which exhibited comparable photocatalytic activity for hydrogen production, achieving 35.5 mmol g-1 h-1 and maintaining long-term stability for 150 h. The outstanding performance was attributed to the ability of the TiO2/(MoP/CdS) composite photocatalysts to absorb both visible and ultraviolet light. Additionally, the heterojunction formed between TiO2 and CdS also played a significant role in the overall photocatalyst activity. This cost-effective catalyst holds promise for future large-scale industrial applications.

Heteroatom Structural Engineering of Conjugated Porous Polymers Enhances Photocatalytic Nicotinamide Cofactor Regeneration.

Photocatalysis is an eco-friendly method to regenerate nicotinamide (NADH) cofactors, which is essential for biotransformation over oxidoreductases. Organic polymers exhibit high stability, biocompatibility and functional designability as photocatalysts, but still suffering from rapid charge recombination. Herewith the heteroatom structural engineering of donor-π-acceptor (D-π-A) conjugated porous polymers were conducted to promote charge transfer and photocatalytic NADH regeneration. The electron delocalization of polymer photocatalysts can be readily tuned by changing the electron density of the donor unit, leading to faster charge separation and better photocatalytic performance. The optimum sulfur-doped polymer exhibits the highest NADH regeneration yield of 47.4 % in 30 min and 94.1 % in 4 h, which can drive the biocatalytic C=C bond reduction of 2-cyclohexen-1-one by ene-reductase, giving the corresponding cyclohexanone yield of 96.7 % in 10 h. Moreover, the oxygen-doped polymer, from biomass derived 2,5-diformylfuran, exhibits comparable photocatalytic activity to the sulfur-doped CPP, suggesting the potential of furan as alternative donor unit to thiophene.

Rational Design of S-Scheme Heterojunction toward Efficient Photocatalytic Cellulose Reforming for H2 and Formic Acid in Pure Water.

Photocatalytic cellulose reforming usually requires harsh conditions due to its sluggish kinetics. Here, a hollow structural S-scheme heterojunction of ZnSe and oxygen vacancy enriched TiO2 , namely, h-ZnSe/Pt@TiO2 , is designed and fabricated, with which the photocatalytic reforming of cellulose for H2 and formic acid is realized in pure water. H2 and formic acid productivity of 1858 and 372µmol g-1 h-1 and a steady H2 evolution for 300 h are achieved with α-cellulose. Comparable photocatalytic activity can also be achieved using various cellulose sources. It is experimentally proven that the photogenerated charge transfer follows an S-scheme mechanism, which not only promotes the charge separation but also preserves the higher reductive and oxidative abilities of the ZnSe and TiO2 , respectively. Furthermore, the polyhydroxy species produced during cellulose degradation are favored to adsorb on the oxygen vacancy enriched TiO2 surface, which promotes the photocatalytic reforming process and is accounted to the preservation of formic acid as the major solution-phase product. In addition, sequential reactions of oxidation of aldehydes and elimination of formic acid of the cellulose degradation process are revealed. This work provides a photocatalytic strategy to sustainably produce hydrogen and value-added chemicals from biomass under the most environmentally benign condition, i.e., pure water.

Influence of nickel doping and cotton stalk activated carbon loading on structural, optical, and photocatalytic properties of zinc oxide nanoparticles

In the current study, the photodegradation of brilliant green (BG) dye has been studied in relation to the comparative photocatalytic activity of pure ZnO and Ni-doped ZnO/CSAC (cotton stalk activated carbon), which was produced using a chemical precipitation method. The structural, optical, morphological, and functional characteristics of Ni-doped ZnO/CSAC have been investigated. The XRD patterns demonstrated the hexagonal wurtzite structure of the Ni-doped ZnO/CSAC sample. The XPS scan supported a Ni2+ oxidation state for the Ni ions incorporated into the ZnO lattice. The optical features of the Ni-doped and loaded sample demonstrated a red shift in the light absorption and reduced the recombination rate of charge carriers. The FE-SEM was used to examine the morphology of the synthesized all the samples, and EDAX spectroscopy was used to determine their composition. In comparison to pure ZnO, Ni doped, and Ni (0.075 M) doped ZnO/CSAC exhibited a greater photocatalytic degradation of 91.47 % after 120 min under visible light irradiation. This result suggests that Ni-doped ZnO/CSAC may be an effective wastewater treatment material.

Enhanced photocatalytic activity of Cu and Ni-doped ZnO nanostructures: A comparative study of methyl orange dye degradation in aqueous solution

Heterogeneous photocatalysis has been considered one of the most effective and efficient techniques to remove organic contaminants from wastewater. The present work was designed to examine the photocatalytic performance of metal (Cu and Ni) doped ZnO nanocomposites in methyl orange (MO) dye degradation under UV light illumination. The wurtzite hexagonal structure was observed for both undoped/doped ZnO and a crystalline size ranging between 8.84 ± 0.71 to 12.91 ± 0.84 nm by X-ray diffraction (XRD) analysis. The scanning electron microscope (SEM) and energy dispersive X-ray (EDX) revealed the irregular spherical shape with particle diameter (34.43 ± 6.03 to 26.43 ± 4.14 nm) and ensured the purity of the individual elemental composition respectively. The chemical bonds (O–H group) and binding energy (1021.8 eV) were identified by Fourier transform infrared (FTIR) and X-ray photoelectron spectroscopy (XPS) results respectively. The bandgap energy was decreased from 3.44 to 3.16 eV when Ni dopant was added to the ZnO lattice. The comparative photocatalytic activity was observed in undoped and doped nanocomposites and found to be 76.31%, 81.95%, 89.30%, and 83.39% for ZnO, Cu/ZnO, Ni/ZnO, and Cu/Ni/ZnO photocatalysts, respectively, for a particular dose (0.210 g) and dye concentration (10 mg L−1) after 180 min illumination of UV light. The photocatalytic performance was increased up to 94.40% with the increase of pH (12.0) whereas reduced (35.12%) with an increase in initial dye concentration (40 mg L−1) using Ni/ZnO nanocomposite. The Ni/ZnO nanocomposite showed excellent reusability and was found 81% after four consecutive cycles. The best-fitted reaction kinetics was followed by pseudo-first-order and found reaction rate constant (0.0117 min−1) using Ni/ZnO nanocomposite. The enhanced photodegradation efficiency was observed due to decreases in bandgap energy and the crystalline size of the photocatalyst. Therefore, Ni/ZnO nanocomposite could be used as an emerging photocatalyst to degrade bio-persistent organic dye compounds from textile wastewater.

Enhanced photocatalytic performance of PS/F-PANI/PNT films for visible-light-induced hydrogen production

This study aims to develop polystyrene/polyaniline/Pt/N-TiO2 (PS/PANI/PNT) photocatalytic films for hydrogen production under simulated sunlight to improve the efficiency of photocatalyst recycling. The effects of the molar ratio of aniline monomer (AN) to oxidizing reagent (ammonium peroxydisulfate, APS) and the weight ratio of AN to PNT on the conductivity of synthesized nanofiber PANI (F-PANI) materials were investigated. PS/PANI/PNT with F-PANI/PNT were synthesized for photocatalytic hydrogen production. An AN/APS molar ratio of 1:2 in F-PANI/PNT was suitable for AN oxidation. The conductive pathway of PANI chains was enhanced by PNT addition at a AN/PNT weight ratio of 1:0.25, which was favorable for enhancing conductivity, facilitating the faster migration of electron–hole pairs to the photocatalyst surface to improve the hydrogen production rate. The F-PANI/PNT photocatalyst effectively separates its electron–hole pairs and has strong electron reduction and hole oxidation abilities, which is suitable for improving the photocatalytic hydrogen production capacity. The contact angle of PS/F-PANI/PNT-2–0.25 was lower than that of PS/PNT, indicating that the hydrophilicity and active sites of PS/F-PANI/PNT-2–0.25 increased. The optimal photocatalytic hydrogen production of F-PS/PANI/PNT (28,580 μmol h-1 g-1) was reached when the polymerization temperature, AN/APS molar ratio, and AN/PNT weight ratio were 5 °C, 1:2, and 1:0.25, respectively. The PS/F-PANI/PNT film showed excellent recyclability, with comparable photocatalytic activity even after five cycle repetition tests. This approach provides a promising alternative to traditional photocatalytic systems and contribute to a more efficient photocatalyst recycling process.

Mechanistic Insights into the High Selectivity and Photocatalytic Activity of Brookite TiO2 toward NOX Abatement

TiO2 nanomaterials are promising photocatalysts for NOx depollution from air under sunlight irradiation. It commonly exists in three phases, i.e., anatase, rutile, and brookite. Anatase, rutile, and a mixture of them are heavily studied. Herein, we have tested the photocatalytic activity of the less studied brookite TiO2 for the NOx depollution from the air. Pure brookite and anatase/brookite mixtures have been synthesized and characterized. Interestingly, we found that brookite TiO2 photocatalyst has a comparable photocatalytic activity to that of the benchmark TiO2 P25, and more importantly, it has higher selectivity toward the conversion of NOx into nitrate ions. The selectivity of brookite TiO2 derived from the TALH precursor is 4.6- and 3.5-fold higher than that of pure anatase and TiO2 P25, respectively. Such impressive selectivity has been explained by measuring the content of physically and chemically adsorbed water, the relative density of defects, and the affinity of NO2 and water adsorption on different anatase and brookite surfaces. The EPR results indicated that brookite TiO2 exhibits a higher density of charge-trapping sites (defects) than anatase. The DFT calculation supported that these defects increase the tendency of brookite (001) surface toward the nondissociative adsorption of NO2, whereas the dissociative adsorption of water is preferred on the perfect surface. It seems that the coexistence of dual sites for the adsorption of molecular NO2 and water-dissociated molecules is crucial for the enhanced selectivity of DeNOx to nitrate ions on brookite TiO2.

Comparative Photocatalytic Activity and Total Organic Carbon Removal Efficiency of TiO2 And ZnO for Reactive Black 5 Photodegradation

AbstractThe photocatalytic performance of TiO2 and ZnO was comparatively studied for photocatalytic degradation of reactive black 5 (RB5) under artificial UVC irradiation. The effect of initial solution pH, catalyst concentration, initial RB5 concentration, purging oxygen rate, stirring rate, and process temperature on the degradation process by TiO2 and ZnO was investigated. In addition, total organic carbon (TOC) analysis has been employed for each parameter to detect the presence of organic intermediates and the photodegradation performance of catalysts simultaneously with the photocatalytic degradation process. The RB5 photodegradation was more rapid in the aqueous medium by TiO2 under UVC irradiation compared to the catalysis by ZnO. On the other hand, the slower photocatalysis by ZnO resulted in generating more organic intermediates. The structural and morphological analyses of photocatalysts TiO2 and ZnO were performed using XRD and FE‐SEM techniques. The UV‐vis spectroscopy measurements supported that the TiO2 demonstrated evidently better photocatalytic activity than ZnO for RB5 degradation.

Synthesis, characterisation and optical studies of CdO-NiO NCs for comparative dye degradation study between two hazardous dyes Congo red and Rose Bengal

In this study, CdO-NiO nano composites (NCs), CdO NPs, NiO NPs were synthesized by the help of chemical co precipitation method and investigated by XRD, SEM, UV–vis, PL and FTIR. Face centered cubic structure having Fm3m space group were observed by the help of XRD for both metal oxides CdO and NiO, their corresponding crystallite size obtained from WH plot are 73 nm and 16 nm presents in CdO-NiO NCs. Similarly we have observed FCC cubic structure for CdO and NiO which are synthesized separately. EDX reveals the elements present with their atomic percentage. Band gap for the NCs was calculated using tauc plot which is around 2.89 eV, 2.74 eV and 4 eV for CdO-NiO NCs, CdO NPs and NiO NPs respectively confirming their semi conducting nature. The presence of bonds Cd-O and Ni-O were confirmed using FTIR. An enhanced comparative photo catalytic activity in the presence of UV light for 140 min was also done for the two hazardous dyes Congo red with 90.18 % degradation [K = 0.0155 min−1, T50 = 45 min] and Rose bengal with 83.53 % degradation [K = 0.0126 min−1, T50 = 55 min] for CdO-NiO NCs. By similar observation for separately synthesized CdO NPs and NiO NPs, the corresponding values obtained are Congo red with 88.86 % degradation [K = 0.0165 min−1, T50 = 42 min], Rose bengal with 79.71 % degradation [K = 0.0117 min−1, T50 = 59.23 min] and Congo red with 87.81 % degradation [K = 0.0164 min−1, T50 = 42.25 min], Rose bengal with 82.68 % degradation [K = 0.0131 min−1, T50 = 52.90 min] respectively.

Photo-catalytic transparent glass-ceramics containing Zn2TiO4 nanocrystals

Photo-catalytic active glass-ceramics have good application prospects in addressing environmental problems and offer advantages over traditional photo-catalyst. Photo-catalytic properties of glass-ceramics mainly depends on the presence of photo-catalytic active nanocrystals embedded inside. Zn2TiO4, as a stable intermediate phase of TiO2-ZnO system, has comparative photo-catalytic activities with traditional photo-catalyst TiO2 and ZnO. In this work, colorless and highly transparent glass-ceramics containing Zn2TiO4 nanocrystals are successfully prepared, and effects of crystallization on microstructure, mechanical, photo-catalytic and recyclable properties are investigated. These Zn2TiO4 nanocrystals embedded glass-ceramics are found to be photo-catalytically active and efficient in photo-degradation of organic dyes. These results show that glass-ceramics containing photo-catalytic nanocrystals are promising for degradation of organic pollutants.

Omnidirectional Hydrogen Generation Based on a Flexible Black Gold Nanotube Array.

Solar-driven hydrogen generation is emerging as an economical and sustainable means of producing renewable energy. However, current photocatalysts for hydrogen generation are mostly powder-based or rigid-substrate-supported, which suffer from limitations, such as difficulties in catalyst regeneration or poor omnidirectional light-harvesting. Here, we report a two-dimensional (2D) flexible photocatalyst based on elastomer-supported black gold nanotube (GNT) arrays with conformal CdS coating and Pt decoration. The highly porous GNT arrays display a strong light-trapping effect, leading to near-complete absorption over almost the entire range of the solar spectrum. In addition, they offer high surface-to-volume ratios promoting efficient photocatalytic reactions. These structural features result in high H2 generation efficiencies. Importantly, our elastomer-supported photocatalyst displays comparable photocatalytic activity even when being mechanically deformed, including bending, stretching, and twisting. We further designed a three-dimensional (3D) tree-like flexible photocatalytic system to mimic Nature's photosynthesis, which demonstrated omnidirectional H2 generation. We believe our strategy represents a promising route in designing next-generation solar-to-fuel systems that rival natural plants.

A comparative photocatalytic activity between PbS NPs and PbS-clinoptilolite towards Cefotaxime

Due to the increased antibiotic pollution of water supplies, a simple and effective clinoptilolite-supported PbS was constructed. XRD results revealed a cubic PbS phase and crystallite sizes of 29, 20, and 17 nm (by the Scherrer formula) and 17, 28, and 28 nm (by the Williamson-Hall formula) for PbS, CNP, and PbS–CNP samples. The absorption edge wavelengths of 802 and 701 nm correspond to the band gap energies (Eg) of 1.55 and 1.77 eV based on the Eg = 1240/λ formula. SEM pictures confirmed a semispherical morphology for the sample on the nanoscale. Despite the negligible role of the direct photolysis, the photodegradation by CNP, PbS, and supported PbS/CNP samples removed 38, 46, and 82% CF molecules. The rate constants (k) of 0.007 min−1 and 0.011 min−1 for CF photodegradation rate by the PbS and PbS/CNP catalysts were obtained, while the k-values of 0.027 min−1 and 0.068 min−1 were respectively obtained as the measure of the photo mineralization extent of CF during the photodegradation.

Simple synthesis of Ag nanoparticles /Cu2O cube photocatalyst at room temperature: Efficient electron transfer improves photocatalytic performance

In this experiment, Ag/Cu2O heterojunction was obtained by directly reducing Ag+ at room temperature in one step, and evaluated its performance of degrading pollutants. Through comparative photocatalytic activity experiments, it can be seen that the degradation effect of the catalyst is much higher than that of Cu2O nanocubes. The amount of Ag particles contained can be controlled by controlling the sum of silver nitrate, and it is found that Ag/Cu2O-3 has the optimal ratio. Through a series of characterization of the prepared samples, it can be concluded that the main reason for the improvement of the photocatalytic performance of the composite photocatalyst is that the presence of Ag improves the transference of photoelectrons, and then accelerates the separation of photoelectrons-holes of Cu2O. In addition, the presence of Ag particles expands the absorption range of Cu2O in visible light region, thereby improving the photocatalytic performance.

Optoelectronic, microstructural, ecofriendly and photo-catalytic evaluation of Aspartic acid cross-linked Poly (vinyl alcohol)/Copper Oxidenanotubescomposite films

The present work describes design and preparation of aspartic acid (Asp) cross-linked Poly (vinyl alcohol) (PVA)/Copper oxide nanotubes (CuO NTs) composite filmsvia solution casting method.The CuO NTswere prepared by novel biogenic method using RobiniaPseudoacaciaLeaf Extract.Theprepared CuO NTs and PVA/CuO/Asp nanocomposite filmsarecharacterized by various techniques.The adsorption and photo-catalytic efficiencies of PVA/CuO/Asp nanocomposite films were compared with pristine CuO NTs. The adsorption capacity of PVA/CuO/Asp nanocomposite films showed higher due to presence of active sites, high surface activity and semiconducting nature of CuO NTs and Asp embedded in PVA matrix. The comparative photocatalytic activities of the CuO NTsand PVA/CuO NTs/Asp nanocomposite filmsare examinedagainst methylene blue (MB) as a substrate degradation, and film PVA/CuO NTs/Asp showed highest (up to 77%) degradation compared to other films. The improved photocatalytic behavior of PVA nanocomposite film attributed to its narrower band gapreduces the recombination rate of exited electron-hole, enhanced UV-Vis absorption intensity, extinction coefficient and refractive index, improved utilization of sunlight and enhanced adsorption of dye due to functional groups, biodegradable, surface wettability, hydrophilic surface and self-cleaning nature.

Microwave-Assisted Vacuum Synthesis of TiO2 Nanocrystalline Powders in One-Pot, One-Step Procedure.

A new method for fast and simple synthesis of crystalline TiO2 nanoparticles with photocatalytic activity was developed by carrying out a classic sol–gel reaction directly under vacuum. The use of microwaves for fast heating of the reaction medium further reduces synthesis times. When the solvent is completely removed by vacuum, the product is obtained in the form of a powder that can be easily redispersed in water to yield a stable nanoparticle suspension, exhibiting a comparable photocatalytic activity with respect to a commercial product. The present methodology can, therefore, be considered a process intensification procedure for the production of nanotitania.

The synergistic effect of anatase and brookite for photocatalytic generation of hydrogen and diclofenac degradation

The development of promising technologies (eco-friendly, cost-effective and simple) for fuel generation and removal of organic pollutants has attracted extensive attention in recent years worldwide. Accordingly, heterogeneous photocatalysis has been considered as most recommended since various chemical reactions could be carried out on the surface of recyclable photocatalysts under sole irradiation (preferably solar). This paper presents the crucial role of the synergistic effect between brookite and anatase titania photocatalysts for their potential application in H2 generation and removal of organic pollutants. Here, a facile hydrothermal treatment of an alkaline solution of Ti2(SO4)3, containing Na+, NH4+, and glycine/Na+ was used to prepare titania photocatalysts in the form of brookite (B), anatase (A), and binary phase (BA), respectively. The comparative photocatalytic activities of obtained photocatalysts and the “standard” P25-TiO2 have been evaluated by the photocatalytic hydrogen evolution (with in situ platinum deposition as a co-catalyst), and photodegradation and mineralization of diclofenac under UV/vis and UV-A, respectively. It has been found that the most active photocatalyst contains 38.2% brookite and 61.8% anatase, has the highest specific surface area (62.3 m2 g-1), and the highest light harvesting ability (absorption edge at 399 nm). The synergistic effect has been confirmed for both tested reactions in comparison to the activities of single-phase photocatalysts. Moreover, the obtained activities are around two times higher than that by famous P25 of similar surface properties. Based on the scavenger tests’ study, the new mechanism for brookite-anatase composites has been proposed, i.e., interparticle charge transfer excitation (ICTE), in which electrons are excited from the valence band (VB) of anatase to the conduction band (CB) of brookite, with simultaneous charge migration according to the heterojunction type II.

Visible light‐assisted degradation of binary mixture of dyes using purple tea‐mediated zinc oxide nanoparticles

AbstractThis work presents completely a new, green, and non‐expensive route of synthesis of zinc oxide (ZnO) nanoparticles (NPs) using purple tea leaves. The crystalline nature of purple tea‐mediated ZnO NPs (PT‐ZnO NPs) was confirmed by XRD and SAED analyses. Further characterizations of PT‐ZnO NPs were done using UV‐vis spectroscopy, FTIR spectroscopy, SEM‐EDX, and TEM. The size of synthesized NPs was calculated to be 15.1 nm which presented spherical morphology with some sorts of agglomeration. The PT‐ZnO NPs when applied as visible light‐driven photocatalyst for degradation of dyes, Malachite green (MG) and Rhodamine B (RB) showed that degradation was found to be higher in their binary solution (MG‐RB) than in their single solution (MG/RB). MG 95% and RB 35% was degraded in their binary solution where as in their respective single dye solution MG 89% and RB 22% got degraded within the experimental time. The highly pure, PT‐ZnO NPs are considered to have comparable photocatalytic activity with respect to most of the reported works and hence might find a way for its practical application for waste water treatment in the real world. The PT‐ZnO NPs could be reused at least for five times without any significant loss in degradation efficiency.

Synthesis, Characterization and Visible-Light Photocatalytic Activity of Solid and TiO2-Supported Uranium Oxycompounds.

In this study, various solid uranium oxycompounds and TiO2-supported materials based on nanocrystalline anatase TiO2 are synthesized using uranyl nitrate hexahydrate as a precursor. All uranium-contained samples are characterized using N2 adsorption, XRD, UV–vis, Raman, TEM, XPS and tested in the oxidation of a volatile organic compound under visible light of the blue region to find correlations between their physicochemical characteristics and photocatalytic activity. Both uranium oxycompounds and TiO2-supported materials are photocatalytically active and are able to completely oxidize gaseous organic compounds under visible light. If compared to the commercial visible-light TiO2 KRONOS® vlp 7000 photocatalyst used as a benchmark, solid uranium oxycompounds exhibit lower or comparable photocatalytic activity under blue light. At the same time, uranium compounds contained uranyl ion with a uranium charge state of 6+, exhibiting much higher activity than other compounds with a lower charge state of uranium. Immobilization of uranyl ions on the surface of nanocrystalline anatase TiO2 allows for substantial increase in visible-light activity. The photonic efficiency of reaction over uranyl-grafted TiO2, 12.2%, is 17 times higher than the efficiency for commercial vlp 7000 photocatalyst. Uranyl-grafted TiO2 has the potential as a visible-light photocatalyst for special areas of application where there is no strict control for use of uranium compounds (e.g., in spaceships or submarines).

Synthesis and comparative photocatalytic activity of CuO layers on SiO2 substrates

Synthesis and comparative photocatalytic activity of CuO layers on SiO2 substrates