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Continuous-flow chemistry has become a mainstream process and a notable trend among emerging technologies for drug synthesis. It is routinely used in academic and industrial laboratories to generate a wide variety of molecules and building blocks. The advantages it provides, in terms of safety, speed, cost efficiency and small-equipment footprint compared to analog batch processes, have been known for some time. What has become even more important in recent years is its compliance with the quality objectives that are required by drug-development protocols that integrate inline analysis and purification tools. There can be no doubt that worldwide government agencies have strongly encouraged the study and implementation of this innovative, sustainable and environmentally friendly technology. In this brief review, we list and evaluate the development and applications of continuous-flow processes for antibiotic synthesis. This work spans the period of 2012–2022 and highlights the main cases in which either active ingredients or their intermediates were produced under continuous flow. We hope that this manuscript will provide an overview of the field and a starting point for a deeper understanding of the impact of flow chemistry on the broad panorama of antibiotic synthesis. [ABSTRACT FROM AUTHOR]

The hydrophilicity of titanium dioxide has been investigated for films, deposited on glass by e-beam evaporation, being exposed to UV radiation and subjected to thermal annealing. The wettability alteration has been showed to depend upon both treatments, and insights into how to introduce more stable hydrophilicity into these films have been presented for the sake of boosting their commercial value. Observations from multiple length scales to assess the wetting behavior of as-deposited and high-temperature annealed samples were assessed through macroscopic measurements, i.e., water contact angle measurements, showing that the annealed crystalline samples, treated at 500 °C, are much more hydrophilic (SCA ≈ 20°) than as-deposited TiO2 films (SCA ≈ 90°), and the nanoscopic experiments performed by amplitude modulation (AM) atomic force microscopy (AFM) indicated that this increased hydrophilicity is related to an enhanced adhesion force and surface energy, resulting in the partial crystallization of TiO2 and the consequent formation of crystals on its surface rather than being related to morphologic differences. XRD and Raman measurements have highlighted that the crystallinity of the TiO2 film is crucial in determining its hydrophilicity, in good agreement with the AFM study. The results also indicated that, after irradiation, the samples treated at 500 °C preserve their hydrophilicity for a significant time compared to previous studies. [ABSTRACT FROM AUTHOR]

Ganciclovir, an active pharmaceutical ingredient against cytomegalovirus, is known to crystallize in the form of anhydrous or hydrated phases. The crystal and molecular structures of two hydrated forms, the hydrochloride salt, and two pro-drug derivatives (i.e., the tri-N²,O,O-acetyl and di-O-acetyl) have been successfully unveiled from powder X-ray diffraction (PXRD) or single-crystal X-ray diffraction studies. The thermal behavior of the hydrates has been unraveled by juxtaposing the results of our thermal analysis and variable-temperature PXRD experiments to those previously reported on the topic. On the whole, this investigation revisits and complements the somehow incomplete and scattered information present in the literature. It is envisaged that this study can open the way to systematic PXRD qualitative and quantitative analysis of ganciclovir mixtures formed during synthesis, isolation, or processing. [ABSTRACT FROM AUTHOR]

Several arguments suggest that the Planck scale could be the characteristic scale of curvature of momentum space. As other recent studies, we assume that the metric of momentum space determines the condition of on-shellness while the momentum space affine connection governs the form of the law of composition of momenta. We show that the possible choices of laws of composition of momenta are more numerous than the possible choices of affine connection on a momentum space. This motivates us to propose a new prescription for associating an affine connection to momentum composition, which we compare to the one most used in the recent literature. We find that the two prescriptions lead to the same picture of the so-called -momentum space, with de Sitter (dS) metric and -Poincaré connection. We then show that in the case of 'proper dS momentum space', with the dS metric and its Levi-Civita connection, the two prescriptions are inequivalent. Our novel prescription leads to a picture of proper dS momentum space which is DSR-relativistic and is characterized by a commutative law of composition of momenta, a possibility for which no explicit curved momentum space picture had been previously found. This momentum space can serve as laboratory for the exploration of the properties of DSR-relativistic theories which are not connected to group-manifold momentum spaces and Hopf algebras, and is a natural test case for the study of momentum spaces with commutative, and yet deformed, laws of composition of momenta. [ABSTRACT FROM AUTHOR]

The objective of this research was to investigate how the photocatalytic activity of pure TiO 2 can be improved by SnO 2 modification. Different molar ratios of tin to titanium were prepared. The correlation between tin concentration and structural properties was investigated to explain the mechanism of photocatalytic efficiency and to optimize the synthesis conditions to obtain enhanced activity of the SnO 2 -modified TiO 2 photocatalysts under UV-irradiation. The SnO 2 -modified TiO 2 photocatalysts were prepared by a low-temperature sol-gel method based on organic tin and titanium precursors. The precursors underwent sol-gel reactions separately to form SnO 2 -TiO 2 sol. The sol-gels were deposited on a glass substrate by a dip-coating technique and dried at 150 °C to obtain the photocatalysts in the form of a thin film. To test the thermal stability of the material, an additional set of photocatalysts was prepared by calcining the dried samples in air at 500 °C. The photocatalytic activity of the samples was determined by measuring the degradation rate of an azo dye. An increase of up to 30% in the photocatalytic activity of the air-dried samples was obtained when the TiO 2 was modified with the SnO 2 in a concentration range of 0.1–1 mol.%. At higher SnO 2 loadings, the photocatalytic activity of the photocatalyst was reduced compared to the unmodified TiO 2. The calcined samples showed an overall reduced photocatalytic activity compared to the air-dried samples. Various characterization techniques (UV-Vis, XRD, N 2 -physisorption, TEM, EDX, SEM, XAS and photoelectrochemical characterization) were used to explain the mechanism for the enhanced and hindered photocatalytic performances of the SnO 2 -modified TiO 2 photocatalysts. The results showed that the nanocrystalline cassiterite SnO 2 is attached to the TiO 2 nanocrystallites through the Sn-O-Ti bonds. In this way, the coupling of two semiconductors, SnO 2 and TiO 2 , was demonstrated. Compared to single-phase photocatalysts, the coupling of semiconductors has a beneficial effect on the separation of charge carriers, which prolongs their lifetime for accessibility to participate in the redox reactions. The maximum increase in activity of the thin films was achieved in the low concentration range (0.1–1 mol.%), which means that an optimal ratio and contact of the two phases is achieved for the given physical parameters such as particle size, shape and specific surface area of the catalyst. [Display omitted] • SnO 2 -modified TiO 2 photocatalysts in the thin film form were prepared by low-temperature sol-gel processing. • An increase of up to 30% in the photocatalytic activity is achieved. • An optimal ratio between TiO 2 and SnO 2 (nano)crystals is achieved in a low concentration range (0.1–1 mol.%). • The coupling of the two semiconductors allows to separate the photogenerated charge carriers. [ABSTRACT FROM AUTHOR]

The construction of photocatalytic systems that have strong redox capability, effective charge separation, and large reactive surfaces is of great scientific and practical interest. Herein, an edge‐connected 2D/2D Z‐scheme system that combines the facet junction and the interfacial heterojunction to achieve effective long‐range charge separation and large reactive surface exposure is designed and fabricated. The heterostructure is realized by the selective growth of 2D‐layered MoS2 nanoflakes on the edge‐sites of thin TiO2 nanosheets via an Au‐promoted photodeposition method. Attributed to the synergetic coupling of the facet junction and the interfacial heterojunction that assures the effective charge separation, and the tremendous but physically separated reactive sites offered by layered MoS2 and highly‐exposed (001) facets of TiO2, respectively, the artificial Z‐scheme exhibits excellent photocatalytic performance in photodegradation tests. Moreover, the junctional plasmonic Au nanoclusters not only act as electron traps to promote the edge‐selective synthesis but also generate "hot electrons" to further boost photocatalytic performance. The Z‐scheme charge‐flow direction in the heterostructure and the roles of electrons and holes are comprehensively studied using in situ irradiated X‐ray photoelectron spectroscopy and photodegradation tests. This work offers a new insight into designing high‐performance Z‐scheme photocatalytic systems. [ABSTRACT FROM AUTHOR]

Doripenem, an ultrabroad spectrum-injectable antibiotic belonging to the wide class of carbapenem beta-lactams, is commonly marketed as powders of a pure monohydrate phase. Here, we have selectively prepared another hydrated phase (a dihydrate) and determined the crystal structure of both forms by state-of-the art powder diffraction methods. Both phases crystallize in the monoclinic P21 space group, and, to some extent, are structurally related. Moreover, by using variable temperature diffractometric analyses, we also discovered a crystalline anhydrous form of doripenem, the structure of which (with two crystallographically independent molecules in the monoclinic P21 space group) remains so far unknown. The thermal interconversion among these phases was further studied by thermogravimetry, differential scanning calorimetry, and thermodiffractometric analyses, and their (metric or stereochemical) mutual relations fully analyzed. The complete structural characterization of the two hydrated phases allows the use of accurate whole pattern profile-fitting procedures for quantitative analyses of these drugs in polycrystalline, or even amorphous, matrices, opening the way to industrial process control and legal protection. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 103:3641-3647, 2014 [ABSTRACT FROM AUTHOR]

Highlights: [•] We report the green synthesis of piperonal by the photocatalytic method. [•] The photocatalytic efficiency of home prepared and commercial TiO2 powders was investigated. [•] The best selectivity (ca. 35%) was obtained by using the home-prepared samples. [ABSTRACT FROM AUTHOR]

Different TiO 2 -based photocatalysts modified with metal species (Pt, Cu 2 O, Nb) have been synthesized and applied in the photo-reforming of glucose and fructose with the aim of linking the photoactivity to some structural and surface characteristics. Bare TiO 2 was inactive towards H 2 production, Cu 2 O was effective in replacing Pt for hydrogen generation, and the presence of Pt/Nb was beneficial for both H 2 production and selective oxidation. Surprisingly, Pt also modifies the surface acid-base properties of catalysts as revealed by DRIFT and TDP measurements in the presence of probe molecules. [Display omitted] • Different modified-TiO 2 photocatalysts were characterized by different surface, structural and textural techniques. • The photoactivity of the samples were compared for the photo-reforming of glucose and fructose. • Both high value-added compounds and hydrogen were produced. • Cu 2 O was effective in replacing Pt for hydrogen generation. • DRIFT and TPD measurements revealed that Pt also modifies the surface acid-base properties of catalysts. Different TiO 2 modified (with Pt, Cu 2 O, Nb) photocatalysts have been compared for the photo-reforming of glucose and fructose at ambient conditions with the aim of linking the photoactivity to some structural and surface characteristics. A different degree of conversion, distribution of intermediates and H 2 production were observed with the various photocatalysts. Moreover, the results obtained with the same catalysts were slightly different with the two substrates, highlighting the importance of the interaction between the catalyst surface and the organic compound. Bare TiO 2 was inactive towards H 2 production, Cu 2 O was effective in replacing Pt for hydrogen generation, and the presence of Pt/Nb was beneficial for both H 2 production and selective oxidation. Moreover, Pt not only works as a sink for the photoproduced electrons, as it is well known in the literature, but also modifies the surface acid-base properties of catalysts as revealed by DRIFT and TPD measurements. [ABSTRACT FROM AUTHOR]

Along with a water-soluble fraction rich in pectin, the hydrodynamic cavitation of citrus processing waste carried out in water demonstrated directly on semi-industrial scale affords an insoluble fraction consisting of micronized cellulose of low crystallinity ("CytroCell"). Lemon and grapefruit CytroCell respectively consist of 100–500 nm wide cellulose nanorods, and of 500–1000 nm wide ramified microfibrils extending for several μm. These findings establish a technically viable route to low crystallinity micronized cellulose laying in between nano- and microcellulose, using water and electricity only. [ABSTRACT FROM AUTHOR]

Abstract: Diflorasone diacetate, a steroid anti-inflammatory drug (marketed as Diacort® or Florone® by Pfizer) and used in the treatment of skin disorders, can be prepared as anhydrous form, DD1 (as deposited in the US pharmacopoeia), or as a monohydrated phase, DDW. Heating the DDW form above 90°C, a mixture of DD1 and of a new anhydrous polymorph, DD2 is obtained. Further heating of this mixture, or of pure DD1, up to 230°C (only a few degrees before melting!), generates an elusive anhydrous DD3 polymorph. Their crystal structures, determined uniquely from laboratory powder diffraction data, show the isomorphous character of the DDW and DD1 forms, while the DD2 and DD3 polymorphs crystallize with markedly different unit cells. Crystals of the DD1, DD2 and DDW forms are orthorhombic, P212121, a =29.386(1)Å; b =10.4310(9)Å, c =8.1422(7)Å, V =2495.8(3)Å3 for DD1; a =15.2639(10)Å; b =11.7506(7)Å, c =13.8931(11)Å, V =2491.9(3)Å3 for DD2; a =30.311(2)Å; b =10.6150(9)Å, c =7.9337(7)Å, V =2552.7(4)Å3 for DDW; while the lattice parameters for the monoclinic P21 DD3 species are a =11.5276(10)Å; b =13.8135(11)Å, c =7.8973(7)Å, β =103.053(6)°, V =1225.0(2)Å3. These compounds have also been fully characterized by thermo analytical methods, as well by 13C, 19F, and 1H NMR spectroscopy. [Copyright &y& Elsevier]

Abstract: Several palladacycle and platinacycle complexes have been prepared from easily available or naturally occurring indole derivatives, such as gramine and related compounds. Dimeric complexes were obtained with Pd(OAc)2, while Pt(DMSO)2Cl2 mainly afforded monomeric structures. A notable feature of these reactions was the formation of new M–C bonds between Pd or Pt and C-2 and C-3 of the indole ring. With ligands like 2-(2′-pyridyl)-1H-indoles, N–N metallacycles were generated instead: in fact new C–M bonds with the C-3 position could only form if N-substituted indoles were used. The reactivity of Pd dimeric complexes with PPh3, sym-collidine and DMAP was explored to obtain monomeric complexes. Three such compounds were prepared, one of which was characterized by X-ray diffraction. Metathetical reactions were carried out to effect a ligand exchange replacing OAc with halide ions, with the aim to synthesize μ-Cl and μ-Br bridged structures. Turning to the synthesis of hetaryl complexes, functionalization of the C-2 position on the indole ring was achieved. These complexes were prepared by substitution reactions starting from gramine and/or its alkylammonium salts. [Copyright &y& Elsevier]

In this article, studies on the photolytic and photocatalytic splitting techniques for the generation of hydrogen from H 2 S in aqueous and gas phase media under ultraviolet and/or visible light irradiation are reviewed. The kinetics of hydrogen production are also thoroughly discussed as a step towards process scale-up. Our findings indicate that the splitting of gaseous H 2 S exhibits greater economic potential but shows much slower kinetics than its aqueous phase counterpart. Recent studies have demonstrated that higher efficiency can be attained with manganese sulfide (MnS) photocatalysts compared to cadmium sulfide (CdS), which in the past has been widely recognized as a promising photocatalyst for the production of H 2 from aqueous H 2 S. Finally, the current challenges faced in implementing light-driven H 2 S splitting and its prospects are highlighted. In particular, it was realized that future work needs to be directed towards the synthesis of novel photocatalysts or the development of reaction conditions that minimize or completely inhibit photo-corrosion, one of the major issues faced during the light-driven production of H 2 from H 2 S in the presence of several photocatalysts. This critical review is envisaged to help fuel the renewed interest in the production of hydrogen through photocatalytic H 2 S splitting. [ABSTRACT FROM AUTHOR]

[Display omitted] Photocatalysis utilizes solar energy to produce clean fuels such as hydrogen or generate highly reactive species to subsequently break the organic pollutants into clean end products. Direct Z-scheme heterostructured photocatalysts can overcome the fundamental shortcomings in conventional photocatalysts and thus enable this green technology in tackling the energy crisis and environmental problems at the same time. Various approaches and numerous materials have been attempted in the hope of achieving high efficiency and broad effectiveness for practical applications. This work intends to provide a comprehensive and timely review on direct Z-scheme photocatalysts from the material's point of view. The formation mechanisms based on the driving forces of the charge transfer are firstly discussed to guide the material design. Three mechanisms, namely internal electric field, interfacial defect-induced charge transfer, and facet-induced charge transfer, are identified and summarized. Various material systems are then extensively discussed and compared according to their applications, followed by the emerging material modification strategies for performance improvement. Lastly, the review provides the perspectives for future development. It is expected that the insights of this up-to-date review could guide the material design and performance improvement of the direct Z-scheme systems to achieve their maximum potentials. [ABSTRACT FROM AUTHOR]

[Display omitted] • TB-coated beads in fixed-bed reactor efficiently degrade DCFA under UV-LED. • Novel kinetic model reveals efficient adsorption and reaction rates in the reactor. • Fixed bed with TB-coated glass beads demonstrates stability over 3 DCFA cycles. • Consistent DCFA degradation confirmed under UV-LED in the fixed bed. • Long-term stability demonstrated; activity maintained over 2 years in fixed bed. In this study, we employed a recirculating photocatalytic fixed-bed reactor featuring a TiO 2 /β-Bi 2 O 3 (TB) composite as a photocatalyst immobilized onto borosilicate glass beads for the degradation of the water-dissolved pharmaceutical compound diclofenac amide (DCFA) under UV-LED illumination. Our findings from the DCFA degradation runs revealed that the initial concentration (Co) and the volumetric recirculation flow rate (Q) exert minimal influence on the DCFA degradation rate, indicating the absence of mass transfer limitations at the chosen Q. A kinetic model, developed in alignment with the experimental data, facilitated the calculation of kinetic adsorption (k 1 = 0.15 (ppm h)-1, K eq = 15 ppm−1, S t = 4.3 ppm) and reaction rate constants (k r = 0.015 h−1). These constants were pivotal in determining the photocatalytic space yield (PSTY—0.45 × (10-6 m3 water m−3 reactor day−1 kW−1 lamp)) for the employed reactor system. The results from three consecutive cycles of DCFA degradation, conducted with the same TB-coated glass beads, demonstrated that the adsorption of DCFA in the dark primarily occurs through the glass material of the beads. Upon exposure to light, the DCFA degradation rate remained constant across all three oxidation cycles. Analysis of the kobs values for cycle 1 (0.0041 ± 0.00067 h−1, R2 = 0.91), cycle 2 (0.0083 ± 0.0013 h−1, R2 = 0.93), and cycle 3 (0.0073 ± 0.001 h−1, R2 = 0.94) indicated an initial excessive leaching of weakly bound TB powder during the first DCFA degradation cycle, potentially resulting in light scattering and reduced photon absorption. Nevertheless, the coatings exhibited reusability over three DCFA degradation cycles, highlighting their stability and reproducible activity. Furthermore, the long-term stability of the coated TB beads was demonstrated by comparing the photocatalytic activity between the present day and two years ago. Remarkably, comparable activity levels were achieved both today (k obs = 0.0085 ± 0.0035 h−1, R2 = 0.71) and two years ago (k obs = 0.0071 ± 0.0014 h−1, R2 = 0.90). These obtained results offer valuable insights for the refinement and optimization of fixed-bed photoreactors in the context of wastewater treatment. [ABSTRACT FROM AUTHOR]

• Surface modification of 3D printed feed spacers was studied for scaling control in MD. • FS nanoparticles coating on spacer favorably altered the latter's surface chemistry. • Increased hydrophobicity and reduced SFE are the main mechanisms of performance. • Scaling reduced by 74% and 60% on the spacer and the membrane, respectively. Surface modification of feed spacers rather than membranes may hold more merit as an antiscaling strategy in membrane distillation (MD), as it avoids compromising the functionality of MD membrane. In this work, an antiscaling polyamide 3D printed spacer was developed for MD. The surface of the printed spacer was coated with fluorinated silica (FS) nanoparticles synthesized via a sol-gel process. The sol-gel approach used to synthesize the FS nanoparticles is considered a convenient and easy approach for engineering the spacer's surface structure and roughness. The performance of the FS coated printed surface was evaluated against other coating materials of different chemical properties. The coated surfaces were characterized using water contact angle measurements, ATR-FTIR, Raman, FESEM-EDX, atomic force and 3D microscopes. The 3D printed surface's microscale roughness and hydrophobicity increased, while its surface-free energy decreased with FS nanoparticles coating. The antiscaling performance of uncoated and FS coated spacers was then assessed in a direct contact MD process, using a scale-inducing aqueous solution of calcium sulfate as its feed. The scalant (Ca2+) attachment on the FS coated spacer was 0.24 mg cm−2, 74% lower than on the uncoated 3D spacer (0.95 mg cm−2). Also, by using the antiscaling FS coated spacer, scaling on the membrane surface dropped by 60%. The predominant factors that helped minimize scaling with FS coating were microscale roughness-induced hydrophobicity and reduced surface-free energy that weakened the scalant 's interaction with the spacer surface. Image, graphical abstract [ABSTRACT FROM AUTHOR]

• Films were deposited by either the sol-gel (SG) or the sputtering (SP) technique. • The porosity of SG films allows BPA to better access the catalytic sites. • SP films have oxygen vacancies acting as charge recombination centers. • N or Cu doped TiO 2 thin films are catalytic active under visible light radiation. • The bilayer samples did not show any improvement of the photocatalytic performance. In this work, TiO 2 thin films were deposited onto soda lime glass substrate by two different techniques: sol-gel (SG) and sputtering (SP). The photocatalytic film performance was assessed in a batch recycle reactor testing the photocatalytic degradation of aqueous solutions of bisphenol A (BPA). The use of supported catalysts in batch recycle reactor systems for the photocatalytic degradation of organic pollutants in waste water can be an alternative to nowadays more used slurry batch reactor systems and powdered catalysts, since it is more economically sustainable and not requiring the removal of catalyst particles after waste water treatment. The best photocatalytic activities were achieved with SG films due to their porosity, which allows BPA molecule to better access the catalytic site than in case of SP films. Raman spectroscopy also showed that SP films have more oxygen vacancies, which may end up acting as charge recombination centers. Doping of TiO 2 thin films, either with N or Cu, enabled us to trigger the catalytic activity of films also under UV-free visible light radiation. Regardless the order of stacking in the double-layered films, the latter did not result in an increased catalytic activity towards the photodegradation of BPA. [ABSTRACT FROM AUTHOR]

Photocatalytic hydrogen production from alkanol-amines as sacrificial agents by using Cu-modified TiO 2 –P25 prepared via in situ photodeposition of cupric ions under UV-A light irradiation was investigated. A direct comparison among different sacrificial agents (monoethanolamine, diethanolamine, and triethanolamine) was preliminarily performed. Diethanolamine was selected for further investigation, due to its higher hydrogen production rate with respect to other alkanol-amines. Effect of pH, starting concentration of sacrificial agent, and catalyst/co-catalyst loads were studied. Solution pH exerts major impact on the photoefficiency for hydrogen generation: reaction mechanisms at different pH values were extensively examined. For the first time, a validated kinetic model estimated the unknown rate constants of (i) reaction between diethanolamine and photogenerated holes, (ii) proton reduction, and (iii) diethanolamine adsorption on the photocatalyst surface. Image 1 • Photocatalytic hydrogen production from alkanol-amines was investigated. • Cu-modified TiO 2 –P25 via in situ photodeposition of cupric ions was prepared. • A validated kinetic modeling allowed the estimation of the unknown rate constants. • Light-to-chemical energy efficiency and quantum yield values were calculated. [ABSTRACT FROM AUTHOR]

Solar energy exploitation is one of the most challenging applications for sustainable energy production. In this work a photoactivated fuel cell was developed, using visible light and the Fe(III)/Fe(II) redox couple for the simultaneous production of electrical energy and oxidation of polluting organics (alcohols) contained in synthetic and real wastewaters. WO 3 was selected as a cheap and environmentally friendly photocatalyst more efficient than TiO 2 (i) under visible light irradiation and (ii) in the presence of in-situ photodeposited Pd. Pd photodeposition was found to reduce the band gap of bare WO 3 , thus increasing visible light capture and limiting the occurrence of photogenerated hole/electron recombination. Higher photocatalytic performances were recorded over WO 3 –Pd compared to TiO 2 and bare WO 3 , despite the low BET superficial area of WO 3 –Pd (2.34 m2 g−1). Optimal conditions were identified at pH = 2.0 with 2% w/w Pd load. The results also evidenced the influence of the selected sacrificial organics and water matrices. A quantum yield of 84.89% and an energy efficiency of 4.15% were the best results achieved so far for the proposed system. The present photoelectrochemical cell offers a very promising system for electrical energy production by using wastewater from wine manufacturing industry and solar light radiation. Image 1 • A low-priced WO 3 -based fuel cell was developed exploiting visible light. • In situ photodeposited Pd was demonstrated to enhance the catalytic efficiency of WO 3. • Real and synthetic alcohol-containing matrices were used in the process. • A variety of techniques were used to characterize the adopted materials. [ABSTRACT FROM AUTHOR]

• The use of MOFs for photocatalytic CO 2 reduction is very promising. • MOFs can act as both light harvesters and catalytic active sites. • MOFs can be used as co-catalysts improving the reactivity of traditional semiconductors. • MOFs can act as hosts or sacrificial precursors to immobilize a number of structures. Metal-organic frameworks (MOFs) have emerged over the last decades as an interesting class of materials for a plethora of applications due to their flexible tunability in composition, structure and functional properties. In particular, the urgent need to convert CO 2 into useful chemical substances have led to growing attention towards these catalysts as promising candidates for CO 2 capture and storage with the ultimate aim of promoting sustainable pathways to address energy and environmental problems. This review provides an overview of the fundamental factors and recent studies of MOFs for CO 2 photoreduction, pointing out the main strategies adopted in the design and testing of innovative MOFs-based catalysts, where MOFs serve either directly as the only photoactive materials for CO 2 transformation into chemical fuels or as units of hybrid catalytic arrangements to enhance CO 2 conversion. The functionalization of MOFs is a promising approach to improve their photocatalytic activity. Their absorption of visible light can be enhanced either by modification of MOFs structure or by adjusting the organic ligands to contain reactive functional groups, through the inclusion of metal nodes with higher reduction potential, or even through a combination of both strategies. MOFs can also be used as co-catalysts along with other photocatalytic entities, resulting in MOF-based composites with enhanced CO 2 photoreduction. The performance of MOFs-based photocatalysts is analyzed in this review, with a view to emphasizing not only the advantages but also the limitations, over the more traditional semiconductors photocatalysts. At the current stage, the main challenges of these MOFs-based photocatalysts relate to the economic feasibility of industrial-scale processes and to the poor stability of these materials, which is often lost after some runs. It is hoped that this review will help the design of increasingly efficient MOF-based materials for CO 2 reduction and create the needed awareness that more work is still needed in order to be able to actualize and explore the potentials of MOFs in addressing the key issues of environmental sustainability. [ABSTRACT FROM AUTHOR]

An adsorption-diffusion enhancement is demonstrated in edge-connected MoS 2 /Au/TiO 2 Z-scheme photocatalyst which achieves zero-order kinetics in pollutant photodegradation, providing an approach in designing heterostructured photocatalysts and decoupled kinetic analysis for complex photocatalytic system. [Display omitted] • A adsorption-diffusion-enhanced mechanism is designed in a Z-scheme photocatalyst. • Zero-order kinetics are achieved in compound photodegradation. • A mechanism transition from Z-scheme to Type II verifies the kinetic variations. • An improved L-H model is developed to explain all experimental observations. Heterostructured photocatalysts have demonstrated great potential in the photodegradation of organic pollutants, while the surfaces & interfaces of their multiple structural components play critical roles in determining their photocatalytic mechanisms and kinetics. Here, we fabricate an edge-connected MoS 2 /Au/TiO 2 photocatalytic system via a selective photodeposition method and utilize a surface-diffusion mechanism to maximize the synergistic effects among the components. The resultant photocatalytic system behaves as a Z-scheme with well spatially separated redox reaction sites. The optimal catalyst 10 % MS/Au/T exhibited a pseudo 1st-order rate constant of 0.0145 min−1 within 120 min, which is seven times more than that of pristine TiO 2. The edge-deposited MoS 2 in the nanocomposite serves as a reservoir to adsorb and then transport the pollutant molecules rapidly to TiO 2 surface for oxidation. Such a pre-concentration effect, as well as the Z-scheme charge transfer mechanism, has enhanced the overall degradation efficiency, and induced the occurrence of zero-order degradation kinetics. The charge transfer behaviors, the diffusion-enhancement mechanism, zero-order kinetics, and the order transition are then thoroughly studied against the MoS 2 mass loading. 10 % MS/Au/T showed the highest values of zero and first-order constants, which were 0.073 ppm/min and 0.011 min−1, respectively. A diffusion-enhanced model is developed and validated to explain the experimental observations. This work provides meaningful insights into degradation enhancement and kinetic analysis for heterostructured photocatalytic systems. [ABSTRACT FROM AUTHOR]

[Display omitted] • 80% of Ni from MLCCs is leached within 180 min using chloride solutions containing cupric ions at pH = 5.0. • Pure metallic nickel is utilized for process optimization before its application to real matrices. • A shrinking spherical particle model is adopted to analyse experimental data. • Mild conditions allowed efficient Cu and Ni separation via leaching, selective photodeposition, and precipitation. • The Cu photodeposition occurs within 150 min, while Ni in the form of Ni(OH) 2 is obtained by adjusting the solution pH up to 10. • Potential benefits: non-toxic chemicals, mild temp and pH, and solar light utilization. The depletion of primary metal sources and the extensive use of nickel necessitate its extraction from secondary resources. In this study, we employed a chloride-based solution containing cupric ions (NaCl/CuCl 2) to enable a straightforward recovery process for nickel from Ni-containing waste materials. Prior to application in real systems, we evaluated different operating conditions using metallic nickel particles, including chloride and cupric ion concentrations, system temperature, and pH. Optimal efficiency was achieved at T = 60 °C, pH = 5.0, [Cu(II)] 0 = 5.0 × 10−3 M, and [Cl] 0 = 6.0 M, resulting in complete dissolution of metallic Ni (58 ppm) within 180 min. This optimized leaching system was then applied to exhausted nickel-containing multilayer ceramic capacitors (MLCCs) matrixes, leading to 80% Ni recovery. FESEM-EDX and XRD analysis characterized both synthetic and real matrixes. Additionally, we proposed a viable route for selective metal recovery through precipitation and photodeposition on titanium dioxide. Complete copper photodeposition occurred after 150 min, while Ni precipitation as Ni(OH) 2 was achieved by adjusting the solution pH to 10. Experimental data from runs with the synthetic matrix were analyzed using a shrinking spherical particle model. [ABSTRACT FROM AUTHOR]

Soon after the publication of the first pioneering works on heterogeneous photocatalysis, the number of papers on this topic continuously increased. This intriguing field of research is very complex as it endows with an interdisciplinary overview that involves different aspects of chemistry, physics, material and environmental sciences. Even if photocatalytic applications in real processes are often difficult to be implemented and scaled-up, investigations at laboratory scale are easy to be performed, and in some cases they may give rise to misconceptions. For this reason, the present work aims to sum up most of the common experimental techniques and procedures generally used in heterogeneous photocatalysis and to highlight the guidelines and the rules that a rigorous analysis and study of a photocatalytic system must follow. The paper focuses on the importance of standardization of photocatalytic experiments with special attention on the possibility to compare results obtained under different experimental conditions. [ABSTRACT FROM AUTHOR]

Perimidines are a particularly versatile family of heterocyclic compounds, whose properties are exploited in several applications ranging from industrial to medicinal chemistry. The molecular structure of perimidine incorporates a well-known efficient fluorophore, i.e.: 1,8-diaminonaphthalene. The high fluorescence quantum yield shared by most naphthalene derivatives, has enabled their use as stains for bio-imaging and biophysical characterizations. However, fluorescence is dramatically depressed in perimidine as well as in the few of its derivatives analysed so far to this respect. The use of perimidine-like molecules in life sciences might be notably fostered by enhancement of their fluorescence emission. Even more excitingly, the concomitance of both biologically active moieties and a fluorophore in the same molecular structure virtually discloses application of perimidines as drug compounds in state-of-art theranostics protocols. However, somewhat surprisingly, relatively few attempts were made until now in the direction of increasing the performances of perimidines as fluorescent dyes. In this work we present the synthesis and spectroscopic characterization of four perimidine derivatives designed to this aim, two of which result to be endowed with fluorescence quantum yields comparable to 1,8-diaminonaphthalene. A rationalization for such improved behaviour has been attempted employing TD-DFT calculations, which have unravelled the interrelations among bond structure, lone pair conjugation, local electron density changes and fluorescence quantum yield. [ABSTRACT FROM AUTHOR]

X‐ray emission spectroscopy (XES) and X‐ray absorption spectroscopy (XAS) provide a unique opportunity to probe both the highest occupied and the lowest unoccupied states in matter with bulk sensitivity. In this work, a combination of valence‐to‐core XES and pre‐edge XAS techniques are used to determine changes induced in the electronic structure of titanium dioxide doped with nitrogen atoms. Based on the experimental data it is shown that N‐doping leads to incorporation of the p‐states on the occupied electronic site. For the conduction band, a decrease in population of the lowest unoccupied d‐localized orbitals with respect to the d‐delocalized orbitals is observed. As confirmed by theoretical calculations, the N p‐states in TiO2 structure are characterized by higher binding energy than the O p‐states which gives a smaller value of the band‐gap energy for the doped material. The modification of the titanium dioxide valence band by insertion of N p‐states is observed with simultaneous dumping of unoccupied d‐orbitals of titanium. [ABSTRACT FROM AUTHOR]

Phosphorus-modified copper ferrite (P–CuFe 2 O 4) nanoparticles were prepared by a simple sol-gel auto-combustion process and used for the photocatalytic ozonation of lomefloxacin (LOM). The morphology, crystallinity, and structure of the synthesized CuFe 2 O 4 and P–CuFe 2 O 4 nanoparticles were investigated using various techniques. The high-performance liquid chromatography (HPLC) analysis revealed that the degradation of LOM achieved a 99% reduction after a duration of 90 min in the photocatalytic ozonation system. In accordance with the charge-to-mass ratio, four intermediates were proposed with the help of their fragments obtained in LC–MS/MS. The degradation kinetics of lomefloxacin followed a pseudo-first order reaction, and the degradation mechanism was proposed based on the results. P 0.035 Cu 0.965 Fe 2 O 4 showed the highest total organic carbon (TOC) removal with 20.15% in 90 min, highest specific surface area and the highest fluoride and ammonium production using the ion chromatography (IC). The experimental results obtained from the electron paramagnetic resonance (EPR) analysis indicated that the modified P–CuFe 2 O 4 samples exhibited significantly elevated levels of superoxide (. O 2 −) production compared to the CuFe 2 O 4 samples. The findings of this study demonstrate that the introduction of phosphorus modification into the copper ferrite photocatalyst led to an augmentation of both the specific surface area and the total pore volume. Furthermore, the incorporation of phosphorus served to promote the efficient separation of electron-hole pairs by effectively trapping electrons in the conduction band, hence enhancing the degradation efficiency. [Display omitted] • Phosphorus Modified Copper Ferrite (P–CuFe 2 O 4) nanoparticles were successfully synthesized using a sol-gel auto-combustion method. • Phosphorus modification showed interesting improvements over parent materials. • Photocatalytic ozonation exhibited higher efficiency than the photolysis process for the degradation of lomefloxacin. • Ions F− and NH 4 + were found and gradually built up during the reaction. [ABSTRACT FROM AUTHOR]

Two new classes of PCB metabolites were recently discovered: sulfonated-polychlorinated biphenyls (sulfonated-PCBs) and hydroxy-sulfonated-polychlorinated biphenyls (OH-sulfonated-PCBs). These metabolites, originating from PCB degradation, seem to possess more polar characteristics than their parent compounds. However, no other information, such as their chemical identity (CAS number) or their ecotoxicity or toxicity, is available so far, although more than about one hundred different chemicals were observed in soil samples. In addition, their physico-chemical properties are still uncertain since only estimations are available. Here we show the first evidence on the fate of these new classes of contaminants in the environment, producing results from several experiments, to evaluate sulfonated-PCBs and OH-sulfonated-PCBs soil partition coefficients, degradation in soil after 18 months of rhizoremediation, uptake into plant roots and earthworms, as well as a preliminary analytical method to extract and concentrate these chemicals from water. The results give an overview of the expected environmental fate of these chemicals and open questions for further studies. [Display omitted] • Environmental fate features and water analysis for sulfonated PCBs are presented. • These chemicals have smaller soil/water partition coefficients than corresponding PCBs. • Degradation in soil of these new metabolites appears to be as slow as PCBs. • Sulfonated and OH-sulfonated PCBs can accumulate in plant roots. • These chemicals move fast with soil water possibly reaching the aquifer. [ABSTRACT FROM AUTHOR]

Photocatalysis and photocatalytic ozonation under visible light have been applied for the purification of a complex aqueous matrix such as the grey water of Masdar City (UAE), by using N-doped brookite-rutile catalysts. Preliminary runs on 4-nitrophenol (4-NP) solutions allowed to test the reaction system in the presence of a model pollutant and to afford the relevant kinetic parameters of the process. Subsequently, the remediation of grey water effluent has been evaluated in terms of the reduction of total organic carbon (TOC) and bacterial counts. The concentration of the most abundant inorganic ionic species in the effluent has been also monitored during reaction. Photocatalytic ozonation under visible light allowed to reduce the TOC content of the grey water by ca. 60% in the optimized experimental conditions and to reduce the total bacterial count by ca. 97%. The extent of TOC mineralization reached ca. 80% when the photocatalytic ozonation occurred downstream to a preliminary electro-membrane bioreactor (eMBR). Coupling the two processes enhanced the global efficiency. In fact, the eMBR treatment lowered the turbidity and the organic load of the effluent entering the photocatalytic ozonation treatment, which in turn enhanced the extent of purification and disinfection. [ABSTRACT FROM AUTHOR]

Abstract: Multiphase TiO2 was stably modified by vacuum treatment for a dramatic improvement in visible‐light absorption and photocatalytic reactivity. The samples were made of rutile‐brookite, bare or N doped, and were grown on reduced graphene oxide. The stable introduction of Ti3+ species and oxygen vacancies resulting in mitigated electron–hole recombination was identified as the main responsible factor, along with a change in surface charges. [ABSTRACT FROM AUTHOR]

The presence of impurities within multiwalled carbon nanotubes (MWCNTs) have major, but as-yet-unrecognized, effects on the electrochemical behavior of MWCNTs in vanadium redox flow batteries. We show that MWCNTs constitute a high-surface-area, electrically conductive, inactive carbon matrix that acts as a bridge between and a support for carbonaceous impurities that are highly active toward the VO 2+ /VO 2 + redox couple. We use freestanding sheets of MWCNTs, either purified and subsequently not modified with impurities (pure) or purified and subsequently contaminated with carbonaceous impurities (impure), as electrodes to eliminate the need for a substrate and thus undesired mixed kinetics. Electrodes fabricated with pure MWCNTs show low activities; attributed to relatively inactive basal sites. In contrast, impure electrodes show high activities due to the increased number of defects and edge sites resulting from the presence of the impurities. Functionalization of pure MWCNTs surface with oxygen-containing groups substantially improve the activity of the electrodes. However, functionalization is not as effective when carbonaceous impurities are present. The carbonaceous impurities form a continuous debris layer over the nanotube fibers, which reduces the effect of the oxidation treatment. Our results indicate that the impurity content of MWCNTs should be considered in studies of their activity and functionalization. [ABSTRACT FROM AUTHOR]

• CFD model implements radiation field, species transport, and reaction kinetics. • Model was employed to predict both dark adsorption and photocatalytic oxidation. • Model enables estimation of adsorption and apparent kinetic constant (RSS < 0.03). • CFD model revealed elimination of mass transfer limitations in the kinetic regime. An improved multiphysics computational fluid dynamics (CFD) model, which couples radiation field modeling, species transport, and kinetics was developed to determine the dark adsorption–desorption (k ads,m k ads,n , k des,m , k des,n) and apparent reaction rate (k app) constants for the photocatalytic oxidation of diclofenac amide (DCFA) in a recirculating thin-film micro-slit reactor. The photocatalytic oxidation of DCFA under UV irradiation was investigated by changing the initial concentration (C o) (0.73–1.7 ppm) and recirculation flow rate (Q) (0.15–3.73 L h−1). The ratio of estimated adsorption–desorption rate constants by fitting the CFD model to experiments were k ads,m /k ads,n = 0.45, and k des,m /k des,n = 1.5, and k app varied from 1.08 to 1.68 × 10-3 mmol m-3 h−1(W m−2)-0.5 with Q (0.15–3.73 L h−1). The CFD model unveiled the switch from mass transfer to kinetics-controlled oxidation of DCFA. The proposed CFD model can be employed as a rapid and flexible tool for the determination of intrinsic kinetic constants in photocatalytic thin-film MRs in the reaction kinetics regime. [ABSTRACT FROM AUTHOR]

In this work, we report for the first time a unique configuration of N-doped and Cu-doped TiO 2 bilayer. The activity of TiO 2 was improved by combining Cu- and N-doping in a layered thin-film structure. The impact of the stacking order was studied, pointing out how the best arrangement is by far the one with Cu-TiO 2 as the top layer. The results reveal a unique and simple way to enhance the photocatalytic response of TiO 2 in the visible domain. [ABSTRACT FROM AUTHOR]

The synthesis of a novel Cu(II) bifunctional ( N,O,O′ ) coordination polymer, the Cu(PzHP) compound, has been carried out by coupling Cu(II) salts and the newely synthesized H 2 (PzHP) organic linker ( H 2 (PzHP) = 1-[4-(1 H ) -pyrazolyl]-2-methyl-3-hydroxy-4(1 H )-pyridinone). Despite to the numerous attempts done for the growth of suitable single crystals and to the synthetic trials carried out to ameliorate the crystallinity of the Cu(PzHP) coordination polymer, its diffraction pattern was always characterized by a discouraging, less-than-ideal , crystallinity. Notwithstanding the extended disorder, leading to a higher than required space group symmetry, we succeeded in the description of its relevant structural features by following an unconventional route to ab-initio structure solution. In this process consideration on the coordination ability of the ligand and on the space group symmetry have been taken into account to ‘manually’ achieve the initial structural model, highlighting that, in some cases, it is still possible to ascertain by PXRD the crystal structure of a material that shows challenging , broad, PXRD pattern. [ABSTRACT FROM AUTHOR]

Bis-dehydroxycurcumin tert-butyl ester (K2T23) is a derivative of the natural spice curcumin. Curcumin is widely studied for its multiple therapeutic properties, including photosensitized cytotoxicity. However, the full exploitation of curcumin phototoxic potential is hindered by the extreme instability of its excited state, caused by very efficient non radiative decay by means of transfer of the enolic proton to the nearby keto oxygen. K2T23 is designed to exhibit a tautomeric equilibrium shifted toward the diketo conformers with respect to natural curcumin. This property should endow K2T23 with superior excited-state stability when excited in the UVB band, i.e., in correspondence of the diketo conformers absorption peaks, making this compound an interesting candidate for topical photodynamic therapy of, e.g., skin tumors or oral infections. In this work, the tautomeric equilibrium of K2T23 between the keto-enolic and diketo conformers is assessed in the ground state in several organic solvents by UV-visible absorption and by nuclear magnetic resonance. The same tautomeric equilibrium is also probed in the excited-state in the same environments by means of steady-state fluorescence and time-correlated single-photon counting measurements. These techniques are also exploited to elucidate the excited state dynamics and excited-state deactivation pathways of K2T23, which are compared to those determined for several other curcuminoids characterized in previous works of ours. The ability of K2T23 in photosensitizing the production of singlet oxygen is compared with that of curcumin. [ABSTRACT FROM AUTHOR]

SiliaCat Au, a nanoscale gold sol-gel hybrid material, was employed in the selective oxidation of alcohols under solvent-free conditions with oxygen as the primary oxidant. The catalyst is recyclable, and a thorough structural investigation, which included thermogravimetric analysis coupled to mass spectrometry, revealed structural details that will be useful in the development of new applications for this functional material to other areas of catalysis, analytical chemistry, bioimaging, and photonics. [ABSTRACT FROM AUTHOR]

Exemestane, a 3rd-generation aromatase inhibitor, is clinically used in the treatment of breast cancer in postmenopausal women. The key step of the industrial synthetic process, i.e. , a dehydrogenation to introduce the Δ 1 -unsaturation, is normally performed with quinones such as p -chloranil or DDQ. We observed the formation of two different hexacyclic by-products, depending on the quinone used in the oxidation step. These compounds arise from an initial [4+2] cycloaddition between the precursor 6-methylenandrost-4-ene-3,17-dione and the quinone reagent, followed by a twofold dehydrohalogenation (with p -chloranil) or dehydrogenation (with DDQ). The structures of these unprecedented hexacyclic adducts were determined by a combination of mass spectrometry, NMR techniques and crystallographic analysis. [ABSTRACT FROM AUTHOR]

The photocatalytic partial oxidation of 4-methoxybenzyl alcohol (MBA) and 4-nitrobenzyl alcohol (NBA) to corresponding aldehydes or acids was performed in water under simulated solar light at different pH’s by using Pt, Au, Pd and Ag loaded Degussa P25 TiO 2 catalysts, prepared by photoreduction. Bare Degussa P25 TiO 2 was also used as a reference. The metal loaded TiO 2 photocatalysts were characterized by XRD, TEM, ESEM and DRS techniques. The best activity and selectivity results were obtained with Pt loaded TiO 2 . The reactivity results show that metal loading on Degussa P25 sharply promotes the photoactivity and product selectivity towards aldehydes. Moreover, at low pH’s very high aldehyde selectivities were determined for both alcohols. MBA oxidation rate was very high at low pH’s, whereas an opposite trend was observed for NBA, due to the difference of the substituent group. Only from NBA a significant amount 4-nitrobenzoic acid (ca. 50%) was obtained at high pH values. [ABSTRACT FROM AUTHOR]

N-doped brookite-rutile catalysts were prepared using the sol-gel method with different nitrogen precursors, namely urea (CH 4 N 2 O), propionitrile (C 3 H 5 N), ammonium hydroxide (NH 4 OH), ammonium nitrate (NH 4 NO 3 ) and ethylene diamine (C 2 H 8 N 2 ). Testing the photoactivity of the prepared catalysts with 4-nitrophenol revealed that ammonium nitrate was the best doping agent with a nominal N-content of 0.8% (w/w), yielding a 5-fold increase in the pseudo-first order constant of 4-nitrophenol disappearance and a 3-fold increase in the pseudo-first order constant of TOC disappearance, with respect to undoped TiO 2 , when irradiated with LED visible light (>425 nm). In the same experimental conditions, commercial catalysts such as Evonik P25 and mixtures of commercial rutile and brookite failed to work. XRD allowed to identify two crystal phases, i.e. brookite and rutile, and to show that the most active catalyst had the highest brookite and lowest amorphous content, along with the largest rutile crystallites. Through HRTEM, the morphology and crystallinity were further investigated: brookite particles were much smaller and roundish with respect to rutile and the intimate contact between the two phases was also well highlighted. N-doping did not produce oxygen vacancies as shown by Raman spectroscopy; thus, the doping can be considered interstitial rather than substitutional. Surface hydroxylation did not promote oxidation ability, as revealed by TGA-DTA: the most reacting catalyst is the least hydroxylated one. BET revealed that the samples are partially mesoporous (type IV hysteresis), although no template/surfactant was used, and the pore size and volume seemed to affect their activity. UV-vis DRS allowed to extrapolate the band gaps, only slightly narrower for N-doped samples, which, however, showed a pronounced absorption of visible radiation compared to undoped TiO 2 . Photoluminescence showed that the emission due to electron-hole recombination decreases with the N-loading, eventually reaching a minimum plateau for doping amounts just above the optimal one. [ABSTRACT FROM AUTHOR]

Perimidines are extensively studied for their different therapeutic properties, including antiulcer, antifungal, antimicrobial, immunosuppressive and anticancer activities. Moreover, their heterocyclic structure embodies the naphthalene moiety, exploited in bio-imaging and biomolecules staining due to its high fluorescence. In this work we present the spectroscopic characterization of a family of perimidine derivatives, in order to obtain information potentially useful for the design of compounds combining biological activity and detectable fluorescence in physiological environment. [ABSTRACT FROM AUTHOR]

TiO 2 and Cu-TiO 2 thin films were deposited by e-beam evaporation and then annealed at 350 and 500 °C. Their structure, surface morphology and optical properties were studied by X-ray diffraction, scanning electron microscopy, cross-sectional TEM, UV–vis, FT-IR spectroscopy and X-ray absorption spectroscopy. A single-phase source material was used for the first time in the deposition process, thus avoiding preferential evaporation of Cu with respect to TiO 2 , and resulting in an even concentration of Cu in the doped films. The photocatalytic activity was evaluated by degradation of pre-adsorbed methylene blue (MB) in dry conditions and gaseous 2-propanol in oxygen atmosphere under visible and simulated solar light, respectively. Results suggested that high surface hydroxylation of the as-deposited films is an important factor for MB oxidation occurring through a dye-sensitized mechanism activated by visible light absorption. Conversely, the rate of photodegradation of 2-propanol is enhanced in annealed samples due to the greater crystallinity and less electron-hole recombination, with the TiO 2 annealed at 500 °C being the most efficient photocatalyst. However, Cu-doped samples resulted the most active samples during the degradation of MB under visible radiation. Finally, the performance at increasing thickness (250, 500, 1000, up to 2000 nm) was tested for the most reactive films revealing a marked rise in photocatalytic activity up to 1000 nm. [ABSTRACT FROM AUTHOR]

Herein, the first multi-purpose antifouling and foul-release photocatalytic coating based on ORMOSIL thin films doped with nanoflower-like Bi2WO6 is described. Irradiation with visible light of the new films immersed in water produces significant amounts of H2O2 by photocatalytic oxidation of water, and allows the degradation of (bio)organic pollutants at the outer surface of the xerogel film. [ABSTRACT FROM AUTHOR]