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In the present work, we have synthesized sulfone-bridged tetraphenyl porphyrin, 2D polymer 'P' (C44H28N4OySx)n through a one-pot reaction of tetra(p-bromophenyl) porphyrin, S with sulfur powder in DMF. The polymer 'P' has been further reacted with erythrosine B for the fabrication of composite photocatalyst, C (C65H37N4NaOySx)n using donor– acceptor conjugation protocol. Herein, both compounds (P & C) have been well characterized by MAS 13C-NMR, XPS, IR, powder XRD, TGA, SEM-EDX, UV-Vis spectra, and Cyclic Voltammetry. Due to the low HOMO-LUMO band gap energy, the applicability of the composite photocatalyst (C, 2.1 eV) has been studied in terms of oxidation of sulfide to sulfoxide. The present work shows a promising route for the development of sulfone-bridged 2D porphyrin covalent organic framework (COF) and its composite photocatalyst as well as its usage in photocatalytic sulfoxidation reaction. [ABSTRACT FROM AUTHOR]

A series of novel fluoro‐containing hypervalent iodane (III) reagents was designed and synthesized. By employing these novel hypervalent iodane (III) reagents, an efficient visible‐light‐triggered radical cyclization of alkynoates to diversely 3‐fluoroalkylated coumarins was developed under metal free condition. It provided an alternative and environmental friendly approach for the installation of 3‐fluoroalkyl motif into synthetically valuable building block coumarins. [ABSTRACT FROM AUTHOR]

Energy serves as the fundamental assurance for human survival. Within the realm of energy, the C 1 chemical conversion stands out as a crucial process that has safeguarded the evolution of human society. With the introduction of the "double carbon" objective, the focus has shifted towards energy conservation, emission reduction, and environmental friendliness in the domain of C 1 catalytic conversion research. In recent times, the attention of researchers has been captivated by photo-driven C 1 chemical conversion, a method through which C 1 small molecules can be converted into diverse value-added products under ambient conditions. Layered double hydroxides (LDH) have emerged as key players in photo-driven C 1 chemical conversion, thanks to their unique 2D layered structure. This review delves into the most recent advancements in nano-state LDH-based materials for photo-driven C 1 chemical conversion. The exploration encompasses three key aspects: Layered double hydroxides (LDH) precursors functioning as catalysts, LDH derivatives serving as catalysts, and LDH playing the role of a catalyst carrier for photothermal catalytic CO 2 hydrogenation and CH 4 reforming & coupling. The review concludes by highlighting potential challenges that may be encountered in this field in the future. By scrutinizing and discussing the aforementioned research endeavors, this article aim to provide researchers with insights and inspiration for advancing the field of photo-driven C 1 chemistry. [Display omitted] • A review based on layered double hydroxide (LDH) nanomaterials. • LDH as catalysts, LDH derivatives serving as catalysts and as catalyst carrier explored. • CO 2 and CH 4 conversion to useful chemicals via thermal and photo-catalytic routes. • Challenges and prospective in applications of LDH as photocatalysts are summarized. [ABSTRACT FROM AUTHOR]

A visible light‐induced radical ipso‐difluoromethylation of N‐arylpropiolamides to synthesize 3‐difluoromethyl spiro[4.5]trienones was developed for the first time. In this transformation PhI(O2CCHF2)2 was used as difluoromethylation reagent and PhI(OAc)2 was employed as oxidant. Due to the cheap and readily accessible reagents and oxidant as well as the mild reaction conditions, this method is as an efficient and practical strategy for the synthesis of difluoromethyl‐substituted spiro[4.5]trienones. [ABSTRACT FROM AUTHOR]

• Pioneering utilization of nitric acid as a photo-catalyst. • Successful conversion of mesitylene to 3,5-Dimethylbenzaldehyde. • we identify an optimal HNO 3 concentration of 0.2 M for maximizing the yield of 3,5-dimethylbenzaldehyde, highlighting the importance of reaction parameters in photo-catalytic processes. • Mechanistic studies employing scavenger assays suggest the involvement of hydroxyl radicals in the formation of aldehydes. • Synergistic effect with phosphorus corrole photosensitizers. Nitric acid (HNO 3) has garnered attention as a versatile acid reagent in laboratory and industrial settings, primarily known for its role in explosives and fertilizer production. Recent studies have explored its application in catalytic processes, particularly in electro- and photo-catalysis, including its involvement in nitrogen fixation and oxidation. This study investigates the photo-catalytic performance of HNO 3 in the conversion of mesitylene to 3,5-dimethylbenzaldehyde, an industrially significant compound. Our results reveal successful conversion under irradiation conditions, with systematic optimizations indicating an optimal concentration of 0.2 M HNO 3. Mechanistic studies employing scavenger assays suggest the involvement of hydroxyl radicals in the formation of aldehydes. Furthermore, synergistic effects between HNO 3 and phosphorus corrole photosensitizers enhance catalytic performance. Subsequent optimization of reaction conditions yields a maximum yield of 45 % for 3,5-dimethylbenzaldehyde. Expansion of the scope to include toluene derivatives demonstrates varying yields, influenced by substituent effects. Notably, the combination of HNO 3 with the corrole catalyst leads to improved yields compared to HNO 3 alone. These findings underscore the potential of HNO 3 as a photo-catalyst and highlight opportunities for novel catalyst design in practical applications. Mesitylene to 3,5–dimethylbenzaldehyde transformation is successfully conducted via nitric-acid-based photo-catalysis with facile operation. The cooperative synergistic effect is achieved by combining HNO 3 and molecular phosphorus corrole hybrid photo-catalytic system. This work will shed light into new practical applications of HNO 3 industries. [Display omitted] [ABSTRACT FROM AUTHOR]

Crystalline Barium substituted Sr1-xBaxTiO3 (x =0.0, 0.04, and 0.08) system nanomaterials were successfully prepared via modified sol-gel citrate precursor technique at 800°C temperatures. A comparative study of the structural, morphological, optical properties and catalytic activity is reported. Synthesized nanomaterials were analyzed by X-ray diffraction and FTIR. Pristine SrTiO3 compound found to be cubic structure. On substitution of Ba in Sr-site, the slight distortion in XRD diffraction peaks were observed. Photo-catalytic efficiency using UV-Visible Spectroscopy was investigated by photo-degradation of synthetic dye in Laundry wastewater employing solar light, and found to be promising photo-catalysts. The catalytic potentiality was also explored for the synthesis of dihydropyrimidinone using Biginelli reaction and the product was found to increase upto 20% for Sr0.2Ba0.8TiO3 with the highest concentration of Barium. [ABSTRACT FROM AUTHOR]

Silicon, an earth‐abundant material with mature technology, low‐cost manufacturing, and high stability, holds promise to enable the sustainable exploitation of solar energy resources currently under utilized at the world‐scale. Apart from traditional interest in the photovoltaic industry, recent years have seen increasingly large activity in the study of Si‐based photo‐electro‐chemical (PEC) cells for water splitting and CO2 reduction. This research established an exciting area with the potential to address the present environmental crisis originating from unregulated CO2 emission levels. In this review, the recent work on Si‐based PEC devices for large scale production of hydrogen via water splitting, and carbon‐negative technologies for the solar‐driven reduction of CO2 into chemical fuels of industrial interest are summarized. Bias‐assisted and bias‐free PEC architectures are discussed, highlighting the motivations, challenges, functional mechanisms, and commenting on the perspectives related to this field of research both as a science and engineering. [ABSTRACT FROM AUTHOR]

Technologies that cause the least harm to nature from global warming standpoint are becoming called-for. In this regard, photo-catalysis which uses the solar energy for chemical transformations of substances is of great interest for studying possible mechanisms of such processes. At the same time, the use of photo-catalysis significantly expands capabilities of the synthesis of new organic and inorganic materials. Charge phototransfer is always at the heart of photochemical transformations. Such processes can be considered from the point of view of quantum mechanics, and the probability of various mechanisms of the passing processes can be calculated using the apparatus of Green's functions. Analytical expressions for kinetic parameters of the charge transfer process between polyatomic particles in non-regular condensed medium and expressions for the extinction coefficient for appropriate processes of charge photo-transfer are obtained. Based on the analysis of obtained analytical expressions of dark and optical charge transfer processes, correlations between kinetic parameters of these processes are obtained. A methodology for determining kinetic parameters of the charge photo-transfer process on the basis of the shape of light absorption curve by means of the system functioning as the frequency of absorbed photons in various systems is presented. In this respect the general methodology has been applied to various specific processes. A methodology for determining the kinetic parameters of the charge phototransfer process from the shape of the light absorption curve by the system as a function of the frequency of absorbed photons in various systems is presented. The general methodology presented has been applied to various specific processes. [ABSTRACT FROM AUTHOR]

Zinc oxide is recently being used as a magnetic semiconductor with the introduction of mag- netic elements. In this work, we report phase pure synthesis of Mg and Ni co-substituted ZnO to explore its structure, optical, magnetic and photo-catalytic properties. X-ray diffraction analysis reveals the hexagonal wurtzite type structure having P63mc space group without any impurity phase. UV-Vis spectrophotometry demonstrates the variation in bandgap with the addition of Mg and Ni content in ZnO matrix. Magnetic measurements exhibit a clear boosted magnetization in Ni and Mg co-doped compositions with its stable value of bandgap corroborating the structural stability and magnetic tuning for its advanced applications in modern-day spintronic devices. Photo-catalytic measurements performed using methyl green degradation demonstrate an enhanced trend of activity in Mg and Ni co-doped compositions. [ABSTRACT FROM AUTHOR]

The present work is focused on the synthesis of morphology-controlled vertically aligned Zinc oxide (ZnO) nanosheets (NSs) using a high power low-temperature sonochemical process. The synthesis process is a facile and low-temperature process, which can be able to produce large-area, homogeneously-grown, vertically-aligned ZnO NSs with high surface to volume ratio. Also, using the same process, we have developed a low-temperature in-situ method of the magnesium (Mg), doped ZnO NSs with identical structure and morphology. The process is versatile, scalable and can be adopted for synthesizing various other doped morphology controlled nanosheets synthesis. The morphology and structure were confirmed using X-ray diffraction technique, FESEM, TEM/HRTEM while surface composition, bonding and doping were confirmed using XPS and UV–VISIBLE spectroscopy. We obtained 2D few layered thick ZnO nanosheets of flake size 2–5 μm with bandgap ∼3.38 eV, which was increased to ∼3.7 eV due to the Mg doping. Furthermore, we demonstrated the comparative photocatalytic activity of the as-synthesized pristine and doped ZnO nanosheets and found that Mg-doping promotes the faster catalytically active redox reaction, hence; the dye degradation time was 15 min faster compared to the pristine ZnO NSs under identical conditions. We believe that the rate-enhancement in photocatalytic dye degradation of Mg-doped ZnO NSs is obtained due to the faster hole transport properties and low recombination rate. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Decrease in a refinery wastewater generation by reuse has been explored. • Solar light-assisted AOPs have been applied to decrease the energy consumption. • Photo-Fenton process showed best performance as secondary and tertiary treatment. • Biodegradability, toxicity and final TOC and COD values were improved. • Fe concentration in photo-Fenton process has been decreased to discharging limits. Abstract To undertake a better water management in Oil&Gas sector, it is essential to decrease the wastewater generation by increasing the current reused water rates. Focused on this motivation, this study presents the performances of solar-assisted photo-Fenton and heterogeneous photo-catalysis on refinery wastewater treatment for reuse purposes with the aim of zero discharge. While initial tests were made on synthetic refinery wastewater, real case studies were performed with two types of refinery effluent in order to test the feasibility of using AOPs either as a secondary or tertiary treatment. Even though heterogeneous photo-catalysis and a combined process showed promising results for the treatment of the refinery effluents, photo-Fenton treatment revealed a superior effectiveness for application in both secondary and tertiary treatment, considering the improvements on TOC removal, toxicity and biodegradability. Photo-Fenton as secondary treatment resulted as efficient as the biological treatment, reaching final TOC values ca. 20 mg/L and 88% of COD removal presenting values lower than those achieved after the biological treatment. Moreover, a marked increase in the BOD 5 /COD ratio from 0.38 to 0.83 was obtained. Furthermore, as a tertiary treatment, photo-Fenton process either with H 2 O 2 /COD = 10 and H 2 O 2 /Fe2+ = 50 or H 2 O 2 /COD = 4 and H 2 O 2 /Fe2+ = 10 provided a final TOC value <4 mg/L. This result reveals the possibility to reuse the effluent in the refinery plant, thus increasing the sustainability. [ABSTRACT FROM AUTHOR]

Presently, photocatalytic hydrogen generation from water splitting has attractive limelight research towards accomplish green globalization (zero CO2 emission) and considered as fuel source of the future due to their high energy content. Heterogeneous semiconductor/metal hybrid structures are receiving increased attention because of their advanced optical, electrical, and catalytic properties, which result from synergic effects. Herein, we developed an approach to fabricate interwoven Cu core nanowires (Cu NWs) decorated with different weight of ZnO nanorods (ZnO NRs) for photocatalytic applications. The bandgaps of the prepared hybrid structures were calculated by using UV-Vis spectra, their crystalline nature was examined with XRD, the morphology of nanostructures was studied by SEM, and their elemental composition and oxidation states were analyzed by XPS. Their photocatalytic activity was investigated for the production of hydrogen and dye (Rhodamine B) degradation. The Cu NW-ZnO NR hetero-assemblies were found to exhibit high photocatalytic properties, due to the synergetic effects of the unique semiconductor/metal heterojunction. The optimized CuZ2 composite exhibited 7.2 times H2-production and 6.2 times degradation of RhB greater than pure ZnO, respectively. Moreover, ZnO-nanorods can harvest solar light to generate photoelectrons, with subsequent electron transfer through the Cu NWs that might favor photocatalytic processes for many energy applications. [ABSTRACT FROM AUTHOR]

Abstract Lanthanum (La) modified TiO 2 embedded over carbon nanotubes (CNTs) to develop nanocomposite for enhanced photocatalytic hydrogen evolution from glycerol-water mixture has been investigated. The samples, synthesized by sol-gel assisted hydrothermal method, were characterized by XRD, FESEM, HRTEM, FTIR, BET, UV–Visible, Raman and PL spectroscopy. La/TiO 2 anchored CNTs has larger surface area with uniform distribution of La3+ ions. The performance of hybrid assembly was evaluated in a continuous flow slurry photoreactor system under UV–visible light irradiations. The highest H 2 evolution rate of 17265 ppm g-cat−1 h−1 was obtained over 5% La-5% CNTs/TiO 2 NRs, 1.14 folds the amount produced over 5% La-5% CNTs/TiO 2 NPs, 1.53 time than 5% La/TiO 2 and 4.10 folds than using pure TiO 2 NPs. This significant improvement in the photo-activity was obviously due to synergistic effect between La and CNTs, larger BET surface area, cleavage of glycerol by La, appropriate band structure, and hindered charges recombination rate. Among the sacrificial reagents, highest H 2 evolution was obtained using glycerol due to the presence of α-hydrogen atoms attached to carbon atoms. A correlation between BET surface area and photonic flux in terms of photocatalytic H 2 production rate was established to understand the performance of hybrid nanostructures. It was observed that BET surface area and photo-flux utilization for the generation of charge carriers with their efficient separation has significant contribution towards improved H 2 production rate. More interestingly, catalyst persisted prolonged stability with a steady H 2 production in cyclic runs. This study provides promising pathway for constructing composite of La/TiO 2 coupled CNTs for efficient H 2 production under visible light. Graphical abstract Image 1 Highlights • 1D/1D La TiO 2 NRs/CNTs composit for enhanced H 2 production under visible light. • La-CNTs/TiO 2 hybrid yielded H 2 of 17625 ppm g-cat.−1h−1, 4.1 fold higher than TiO 2. • Synergistic effect of La/CNTs promoted TiO 2 activity for dynamic H 2 production. • La-CNTs/TiO 2 prevailed stability in cyclic runs for dynamic H 2 production. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Aliphatic acids are efficient in catalyzing DEP degradation under UV irradiation. • The complexation of aliphatic acids with Fe3+ significantly improves the catalytic abilities. • Polyphenol carboxyl acids have no photocatalytic ability with or without iron coordination. • Hydroxyl substituents on aliphatic acids can improve the catalytic effects of aliphatic acids. • E LUMO significantly negatively influences photocatalytic abilities of aliphatic carboxylic acids. Abstract Diethyl phthalate ester (DEP) can be degraded in Fe3+-UV- aliphatic/phenolic carboxyl acids systems, and the degradation can be significantly influenced by different physical chemical properties of the organic acids. In this study, a density function theory (DFT) approach combined with multilinear regression analysis demonstrates that the lowest unoccupied molecular orbital energy (E LUMO) significantly negatively influenced DEP degradation. The correlation coefficient of the regression is −19.3 mM L−1 h−1. The standardized partial correlation coefficient is −0.674. The aliphatic acids group has higher catalytic ability than the phenolic carboxyl acids group, and by shifting the dominant LUMO configuration from C 3s3d to Fe 4s3d orbitals, Fe3+ significantly accelerates the catalytic reactions of the aliphatic acids/UV systems. Further analysis demonstrates that electron withdrawing hydroxyl group on the aliphatic acids increases the photo catalytic effects of aliphatic acids/UV system. This study highlights the important role of E LUMO of organic acids on their photocatalytic ability towards degradation of organic pollutants. [ABSTRACT FROM AUTHOR]

Abstract Sulfate reducing bacteria (SRB) wreaks havoc in the oil industry by being an agent for oil souring and building corrosion in pipelines and thereby degrade the quality of crude oil. Palladium nanoparticles decorated silicon carbide nanomaterial (Pd-SiC) was synthesized by a facile single step synthesis process and this nanomaterial as a photo-catalyst, as compared to pure silicon carbide (SiC) nanoparticles showed a significant enhancement in the photo-catalytic efficiency in the process of the photo-catalytic deactivation of hazardous SRB. The morphological characterization studies such as Field emission scanning electron microscopy, Transmission electron microscopy, X-ray diffraction, and Fourier transform infrared spectroscopy unambiguously revealed that SiC surface was successfully decorated with palladium (Pd) nanoparticles. Also the Pd nanoparticles decorated on the SiC surface was further substantiated by EDX and elemental mapping analysis, which clearly revealed the presence of Pd along with Si and O. The band gap energy estimated using Diffuse reflectance spectra (DRS) showed the reduction of band gap energy from 2.82 eV to 2.72 eV. The observed enhancement in the efficiency of photo-catalytic deactivation of SRB with Pd-SiC can be attributed to the significant reduction in the recombination of photo-generated charge carriers, characteristically resulting from the metal (Pd) semiconductor (SiC) junction established by this synthesis process. Graphical Abstract Unlabelled Image Highlights • Palladium decorated silicon carbide was synthesized by a single step process. • Characterization studies showed Pd is well placed on the SiC surface. • This material exhibited enhanced photo-catalytic deactivation of SRB. • The complete SRB deactivation in water was achieved in less than 6 min [ABSTRACT FROM AUTHOR]

Amorphous carbon nanotubes were synthesized using low temperature solid state reaction. The as synthesized a-CNTs were used to remove two different textile dyes, Methyl Orange and Rhodamine B from water. Two ways of removal were followed; i.e. Adsorption and UV assisted catalysis. Adsorption experiment was carried out under various conditions. Analysis of the adsorption data was performed using Langmuir, Freundlich and Temkin models. It has been shown that the as prepared samples can effectively be used as adsorbent of textile dyes. Exposure of visible or UV light can make no significant additional effect to the removal efficiency. The mechanism of the adsorption has been found to be following a pseudo 1st order mechanism with corresponding correlation factor >0.95. Also it has been shown that presence of impurities can drastically kill the performance of the sample. This detail comparative study has been reported for the first time. [ABSTRACT FROM AUTHOR]

This paper describes a novel set-up for characterization of the performance of membranes designed for purification of water. It involves a recirculatory system, with continuous monitoring of the concentration in the water of a representative pollutant (Methylene Blue). Pressures, flow rates and temperatures are also measured. Results, in the form of rate constants for reduction in pollutant concentration, are presented for three different types of membrane, all of which incorporate relatively high surface areas of titania and have permeability values in a range making them suitable for this type of processing (∼10 −11 m 2 ). These results are rationalized in terms of the surface areas of the membranes, and the likely water flow characteristics within them. It is concluded that all of the titania surfaces within them have similar efficiencies for photo-catalytic oxidation of pollutants, but there are significant differences in the ways that the water is exposed to these surfaces, and hence in the pollutant oxidation rates. These points are relevant to the optimization of membrane design for this purpose. [ABSTRACT FROM AUTHOR]

Photo-induced CO 2 reforming of CH 4 in the presence of H 2 O over La-modified TiO 2 nanoparticles in a continuous flow photoreactor has been investigated. The structure and properties of the catalyst samples, synthesized by a sol-gel method, were systematically characterized by XRD, Raman, SEM, TEM, CO 2 -TPD, TGA, N 2 -sorption, XPS, UV–Vis DRS and PL spectroscopy. The crystallite size was reduced while, BET surface area and basicity were increased due to the presence of La 2 O 3 . The La-modified TiO 2 nanocatalysts were tested under different catalyst loading, irradiation time, reaction temperature and type of reductants. The main products detected over La/TiO 2 catalysts during photo-induced CO 2 -CH 4 reaction system were CO, H 2 and C 2 H 6 . The amount of CO produced over 5 wt.% La/TiO 2 was 9.6 fold more the amount of CO produced by pure TiO 2 . When H 2 O was added to the CO 2 -CH 4 reaction system, the yield of CO increased 37 fold higher over 5 wt.% La/TiO 2 compared to TiO 2 . The enhanced photocatalytic performances can be attributed to the synergistic effect of La 2 O 3 for CO 2 adsorption with hindered charge recombination rate by La 3+ and appropriate redox potentials. The photocatalytic turnover productivity (PTOP), calculated for the first time, presented amounts of products evolved with the photon energy consumption. The highest PTOP number achieved for CO production using the CO 2 -CH 4 -H 2 O reaction system was 3.83 fold higher than PTOP achieved in CO 2 -CH 4 reaction system. However, PTOP for the production of H 2 and C 2 H 6 in CO 2 -CH 4 system was 1.2 and 2.1 fold higher than the CO 2 -CH 4 -H 2 O reaction system, respectively. The stability test revealed prolonged life time of La/TiO 2 in cyclic runs for dynamic CO 2 -CH 4 conversion to fuels in the presence of H 2 O than using only CO 2 -CH 4 reaction system. Therefore, CO 2 -CH 4 could efficiently be converted to fuels over a La/TiO 2 catalyst while the addition of H 2 O could promote both photoactivity and stability. [ABSTRACT FROM AUTHOR]

As a promising structure in enhancing the photo-catalytic performance of the materials, hollow-shell structure still faces the great challenge of constructing an effective architecture for catalytic application. Herein, multi-shelled hollow microspheres of the visible-light photo-catalyst Bi 2 WO 6 with shells up to the triple (BWO-MSH), have been synthesized by using a facile and effective carbonaceous template route. Intriguingly, the photo-catalytic reaction rate constant of BWO-MSH sample is nearly 16 times higher than the Bi 2 WO 6 prepared through solid-state reaction (BWO-SSR). The single-, double-shelled Bi 2 WO 6 microspheres (Broken) could only be synthesized with lower quality (synthesized with many broken species), and their photo-catalytic performance was nearly the same poor as the BWO-SSR sample. Furthermore, multi-shelled hollow microsphere of Bi 2 O 3 /Bi 2 WO 6 (BO/BWO-MSH) composite was also synthesized. The present work not only extends the scope of high-performance complex mixed metal oxides with multi-shelled microstructures, but also brings a good reference to engineer other impressive photo-catalyst. [ABSTRACT FROM AUTHOR]

In this paper, cyanide degradation (at pH12) using S, N-TiO2 photo-catalyst, synthesized by sol-gel method, stabilized on glass microbeads and scoria stones were investigated. The main raw materials were thiourea (Tu) as a source of S and N and tetra butyl orthotitanate (TBOT). The effects of S and N amount, visible and sun light, irradiation time and different initial cyanide concentrations (50, 100, 200 and 300 mg/L) on destruction of cyanide were studied. The S, N-TiO2 film with 0.25 g thiourea showed the best cyanide destruction in visible light. The results showed that cyanide (50 mg/L) was destructed up to 94% in visible light and approximately 100% in sun light by S, N-TiO2/glass microbead. The results also indicated 85% and 94% destruction in visible and sun light respectively by S, N-TiO2/scoria stone within 4 h. Finally, the S, N-TiO2 stabilized on glass microbeads can be effectively implemented as a new method for treatment of wastewater containing free cyanide under sun light. [ABSTRACT FROM AUTHOR]

We propose g-C 3 N 4 nano-sheets and a graphene three-dimensional (3D) gel system composed of two metal free nano-sheets of g-C 3 N 4 and graphene via the stacking effect of two-dimensional (2D) nano-sheets and the π-π conjugated at low temperature. This material has self-regeneration and containing only C and N, which confirms the ability to efficiently remove chromium (VI) (Cr(VI)) via the synergistic effect of adsorption and photo-catalysis. The graphene sheets offer surface adsorption in the composite, which can lead to the adsorption of Cr (VI) with high adsorption capacity and fast speed. The g-C 3 N 4 nano-sheets have high photocatalytic activity in situ for composite to absorb the high toxicity of Cr (VI). This was rapidly reduced to Cr (III). The adsorption and photocatalytic degradation synergized to achieve self-regeneration. The results showed that 80% Cr (VI) (30 mg/L) can be adsorbed by composite in 30 min, and the removal of Cr (VI) reached 100% in 120 min under visible light irradiation via adsorption and photo-catalysis. The low concentrations (2 mg/L) of Cr (VI) can be achieved via a degradation rate of almost 100% that was maintained for more than 26 h. At the same time, there was a large quantity of hydrogel in the pore space network and micron level structure in the composite. This offers 99% recycling and reuse via a stainless steel filter (pore size 38 μm) without the need to rely on a complex separation system. This solves the difficult problems of powder catalyst recovery. [ABSTRACT FROM AUTHOR]

A mechano-/photo- bi-catalyst of piezoelectric-ZnO@photoelectric-TiO 2 core-shell nanofibers was hydrothermally synthesized for Methyl Orange (10 mg L −1 ) decomposition. The mechano-/photo- bi-catalysis in ZnO@TiO 2 is superior to mechano- or photo-catalysis in decomposing Methyl Orange, which is mainly attributed to the synergy effect of the piezoelectric-ZnO core’s mechano-catalysis and the thin photoelectric TiO 2 shell’s photo-catalysis. The heterostructure of the piezoelectric-ZnO@photoelectric-TiO 2 core-shell interface, being helpful to reduce electron-hole pair recombination and to separate the piezoelectrically-/photoelectric ally- induced electrons and holes, may also make a great contribution to the enhanced catalysis performance. The mechano-/photo-bi-catalysis in ZnO@TiO 2 core-shell nanofibers possesses the advantages of high efficiency, non-toxicity and tractability and is potential in utilizing mechanical/solar energy to deal with dye wastewater. [ABSTRACT FROM AUTHOR]

The development of new classes of photo-active porous materials is of specific interest in photocatalysis and light harvesting applications. Metal organic frameworks (MOFs) provide an excellent platform through which to develop photo-active materials as the large pores can serve as hosts for photo-active guests. Here the photophysical properties of [Ru(1,10-phenanthroline) 3 ] 2+ (RuPhen) encapsulated within a polyhedral Zn(II)-trimesic acid metal organic framework material, hereafter, USF2, are reported. Encapsulation alters the photophysical properties of the RuPhen exhibiting a biphasic decay of the triplet metal to ligand charge transfer state ( 3 MLCT) with lifetimes of 142 ns and 966 ns at 20 °C relative to 320 ns for RuPhen in deaerated ethanol solution. In addition, the encapsulated RuPhen displays a hypsochromic shift in the steady state emission relative to RuPhen in ethanol from 586 nm to 579 nm. These results are quite distinct from the corresponding RuBpy@USF2 and it is suggested that RuBpy and RuPhen encapsulate within different cavities of the USF2 framework. [ABSTRACT FROM AUTHOR]

Low temperature pure anatase Carbon Doped Titanium Dioxide (C-TiO2) is successfully synthesized by using starch as an effective, economical, and nonhazardous carbon source. The synthesized C-TiO2 has been further characterized by X-Ray Diffraction, SEM, TEM, BET, XPS and UV- DRS techniques, which reveal that the particles are crystalline with spherical morphology, high surface area and an optical band gap of 2.79eV for C-TiO2 calcined at 400°C. Furthermore photocatalytic degradation of Rhodamine B dye was carried out using as-prepared C-TiO2 under visible light irradiation. Prepared C-TiO2 calcined at 200°C and 400°C show higher degradation efficiency (85% and 100% in 120min respectively) as compared to that of undoped TiO2 and commercial Degussa P-25. Result shows that the C-TiO2 containing lower carbon percentage has higher photocatalytic activity. Thus enhanced photocatalytic activity of C-TiO2, may be due to synergic effect of carbon doping and [101] facet enhanced synthesis of anatase C-TiO2. [ABSTRACT FROM AUTHOR]

Using TiO 2 on slides to facilitate photo-catalysis of silver nano-particles (AgNPs) is a simple and versatile way of making silver based solid SERS substrates. However, due to the difficulty of getting optimal surface AgNPs structure, it is difficult to reach optimal enhancement factor or measurement uniformity with this method. In this research, production conditions and setups, ranging from dip-coating to photo-catalysis are investigated. Spectral analysis show that some conditions, such as time of calcination and the purity of UV light used in photo-catalysis, affect the resulting SERS substrates more significantly. The overall performance of substrates made using this method is increased; sensitivity is increased so that the limit of detection for Rhodamin 6G (R6G) is as low as 10 −8 M, and the signature peak of R6G at 1650 cm −1 measured from different spots on substrates has a standard deviation of less than 20%. [ABSTRACT FROM AUTHOR]

In this study, we prepared a new visible light induced photo-catalyst Ag/FeOOH/SBA-15 using a facile deposition–photo-reduction method. Transmission electron-microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and N 2 adsorption–desorption isotherm techniques were used to study the morphology form, structure and the valence state of the nano-materials. According to UV–vis absorption spectra, Ag/α-FeOOH/SBA-15 had a better response to visible light than α-FeOOH/SBA-15. Phenol of 20 mg/L was used as a representative organic pollutant to evaluate the photo-catalytic efficiency of Ag/α-FeOOH/SBA-15 and α-FeOOH/SBA-15 catalysts in visible light (λ > 400 nm), 93% and 78% of phenol degradations could be achieved over Ag/α-FeOOH/SBA-15 and FeOOH/SBA-15 catalysts with 5 mmol/L H 2 O 2 in 4 h. Moreover, the mechanism suggested that the high photo-catalytic activity is due to the charge separation, the surface plasmon resonance of metallic Ag particles in the region of visible light and generation of hydroxyl radical. This work is of importance in theory research and practical application of complex nano-composite. [ABSTRACT FROM AUTHOR]

Bismuth selenide (Bi 2 Se 3 ) and nickel (Ni) doped Bi 2 Se 3 were prepared by a solvothermal approach to explore the photo-catalytic performance of the materials in degradation of malachite green (MG). The presence of nickel was confirmed by X-ray photoelectron spectroscopy (XPS) measurement in doped Bi 2 Se 3 . The results showed that the nickel doping played an important role in microstructure and photo-catalytic activity of the samples. Nickel doped Bi 2 Se 3 sample exhibited higher photo-catalytic activity than that of the pure Bi 2 Se 3 sample under visible-light irradiation. The photo-catalytic degradation followed first-order reaction kinetics. Fast degradation kinetics and complete (100% in 5 min of visible light irradiation) removal of MG was achieved by nickel doped Bi 2 Se 3 in presence of hydrogen peroxide (H 2 O 2 ) due to modification of band gap energies leading to suppression of photo-generated electron-hole recombination. [ABSTRACT FROM AUTHOR]

One of the shortcomings of solar disinfection of water (SODIS) is the absence of a feedback mechanism indicating treatment completion. This work presents the development of an automated batch-process water disinfection system aimed at solving this challenge. Locally sourced materials in addition to an Arduinomicro processor were used to control the algorithm of the water disinfection system. A comparison of solar radiation sensing accuracy of the system to the Campbell Stokes instrument using student's t-test showed no significance difference between the two data sets at p=0.05. Test conducted with Escherichia Coli spiked water shows that a 6 log reduction in CFU/ml was achieved within 15 minutes for an average global solar irradiance of 400 W/m2. The system disinfected 11 litres of water in a day for solar radiation of 8.5 MJ/m²/day and Escherichia coli concentration not exceeding 106 CFU/ml. [ABSTRACT FROM AUTHOR]

Photocatalysis by visible light is important for a wide range of applications. In this work, graphene oxide (GO) based hybrid photocatalyst ZnO/(Fe 3 O 4 @SiO 2 )/rGO (GZF) composites were prepared via microwave synthesis by introducing ZnO nanoparticles (ZnO NPs) and Fe 3 O 4 @SiO 2 onto the surface of reduced GO (rGO). GZF composites possess magnetism therefore easy to separate from the solution simply by a hand-held magnet. They exhibit excellent photo-catalysis for the oxidative degradation of methylene blue, which is 3.6 times higher under visible light when compared to the ZnO NPs. The surface defects in the ZnO nanoparticles before and after graphene hybridization were studied. The optical results show that the visible emission consists of violet, blue and green regions, attributed to the zinc interstitial, zinc vacancy and oxygen vacancy defects. After hybridization with the graphene the vacancy sites in the ZnO nanoparticles were significantly decreased, oxygen vacancies were healed, albeit oxygen interstitial defect (O i ) levels appeared as a new defect. The superoxide and hydroxyl radicals are responsible for the photocatalytic reaction. The present results are important for exploring graphene based magnetic photocatalysts for various applications. [ABSTRACT FROM AUTHOR]

Atrazine is one of the most extensively used herbicides. Being non-biodegradable in nature, it has a long half-life in water and hence it is prone to contaminate the water bodies and even seeps into the ground to pollute underground water. In this study, we developed a photocatalytic method for the degradation of Atrazine in water samples. Highly ordered mesoporous Ag-WO 3 /SBA-15 composites were tested as photocatalysts for the degradation of atrazine in water. It was found that 40% WO 3 loading rendered an optimum surface area and material content in the SBA-15 template and hence favored the enhanced photocatalytic degradation of atrazine in water. The further addition of Ag onto the WO 3 /SBA-15 composite not only made this catalyst very effective in the most sought visible region due to solar energy harvesting, but also significantly reduced the electron hole recombination as evidenced by photoluminescence studies to enhance the degradation efficiency. As a result, the Ag-WO 3 /SBA-15 composite the photo-catalytic degradation of atrazine in water under visible radiation was significantly enhanced. [ABSTRACT FROM AUTHOR]

A series of Mn x Cd 1−x S (MCS) solid solutions hollow spheres (x=0.0, 0.20, 0.33, 0.50 and 0.67) have been synthesized with the assistance of l -Glutathione (GSH) by a simple hydrothermal route for the first time. Different characterization techniques, including X-Ray diffraction (XRD), atomic absorption spectroscopy (AAS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer-Emmett-Teller surface area (BET), UV–vis and diffuse reflectance spectra (DRS) are performed to investigate the structural and optical properties of the as-prepared samples. The experiment of rhodamine B (RhB) decoloration indicates that all the MCS samples show higher photo-catalytic activities than commercial CdS under visible light irradiation. Among them, the Mn 0.33 Cd 0.67 S exhibits the highest photo-catalytic activity. The superior photo-catalytic activity of MCS samples may be attributed predominantly to the synergistic effect of the appropriate band-gap structure as well as the special hollow spherical morphology which makes MCS samples have the ability to harvest exciting visible-light due to multiple scattering within the interior space. Furthermore, the Mn 0.33 Cd 0.67 S shows well stability, the photo-catalytic activities do not decrease significantly after six recycles. The work may open a novel strategy to fabricate multi-component chalcogenide solid solutions hollow spheres. [ABSTRACT FROM AUTHOR]

The aim of this work was to study the photocatalytic degradation of Methylene Blue and phenol by nano-particles coated on diatomite as a new nano-composite catalyst. Titanium dioxide (Degussa P25) was immobilized on diatomite powder at different compositions by a very simple and low cost technique. Diatomite powder (also called Kieselguhr) is an Algerian substance with a snow-white color and porosity greater than 72%. High porosity allowed the diatomite powder to float on the surface of water providing a means for the treatment process that enabled separation from water without any need for pumping as well as the exposure to solar radiation when supported beneath titanium dioxide (TiO2) during photocatalysis. The morphology characterization of the prepared catalysts was carried out by X-ray diffraction analysis, scanning electron microscopy and infrared spectroscopy (IR). Photocatalytic activity was initially tested in a single reactor followed by pH, conductivity and absorbance analyses. Photocatalytic treatment of synthetically polluted water with Methylene Blue and phenol showed good performance for the two new nano-composites using immobilized TiO2on diatomite. [ABSTRACT FROM PUBLISHER]

Four novel [2Fe2S] model complexes ( 1 – 4) had been synthesized and characterized by IR, 1 H NMR, elemental analysis and single crystal X-ray crystallography (for 2 ). The key parameters affecting H 2 evolution of title compounds ( 1 – 4) were optimized by constructing homogeneous photo-catalytic system consisting of title compounds ( 1 – 4) as catalyst, erythrosin B sodium salt (EBS 2 − ) as photo-sensitizer (PS) and triethylamine (TEA) as sacrificial reagent in CH 3 CN/H 2 O solution under the irradiation of visible light. The maximum H 2 evolution was separately 211.4 ± 6.5 μmol (52.9 ± 1.6 TON vs. 4) , 199.4 ± 13.5 μmol (49.9 ± 3.4 TON vs. 1 ), 124.8 ± 7.6 μmol (31.2 ± 1.9 TON vs. 3 ) and 34.9 ± 6.9 μmol (8.7 ± 1.7 TON vs. 2 ) under the optimal conditions with catalyst of 2 × 10 −4 mol·L −1 , EBS 2 − of 4 × 10 −4 mol·L −1 , TEA of 10% (v/v) and pH 12 in CH 3 CN/H 2 O (1/1, v/v) solution. Furthermore, the structural effect and mechanism of electron transfer in the present system was carefully discussed by fluorescence spectra and cyclic voltammetry (CV) measurements. [ABSTRACT FROM AUTHOR]

A heterojunction thin film consisting of n-type titanium dioxide (TiO) and p-type cuprous oxide (CuO) was fabricated on an FTO conducting glass. The TiO films were grown on the FTO glass by sol-gel and spray pyrolysis methods, and CuO was deposited on it via the hydrothermal method. The morphology, crystalline structure, and optical absorption characteristics were studied by scanning electron microscopy, X-ray diffraction, and ultraviolet-visible diffuse reflectance spectrum, respectively. The results show that the surface of the CuO/TiO film was composed of net and large grains, which contributed to a large specific surface area. The crystal phase of the TiO in the CuO/TiO film remained anatase. The crystal phase of the CuO could not be detected as it is found in traces. The CuO/TiO film had a stronger optical absorption ability than the pure TiO film. To investigate catalytic activity, a photocatalytic degradation experiment of the CuO/TiO film was performed in a homemade thin-layer micro-reactor. The photocatalytic degradation of methylene blue increased with increasing amounts of deposited CuO until a maximum limit was reached. The photocatalytic activity might have declined with an increase in CuO content. The metallic oxide has the potential to screen other photocatalysts from the UV source. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the photo-catalytic properties of nitrogen-doped titanium dioxide nano-particles supported on polymer membranes in the photo-reduction of Fe3+ and Pb2+ from synthetic wastewater. The morphology of the prepared N-TiO2 nanoparticles was evaluated using transmission electron microscopy. Successful grafting of methacrylic acid side chains onto poly(vinylidene difluoride) (PVDF) backbone was confirmed by Fourier-transform infrared spectroscopy. The photo-catalytic asymmetric membranes were prepared through the dry-wet phase inversion technique. The asymmetric morphology was evaluated using scanning electron microscopy. The highest Fe3+ photo-reduction efficiency (76.2%) was achieved in 6 hours using 1% N-TiO2-PMAA-g-PVDF/PAN (PMAA: poly(methacrylic acid); PAN: poly(acrylonitrile)) asymmetric membrane under solar irradiation. Increasing the photo-catalyst loading to 3% was found to negatively impact the photoreduction of Fe3+. Very high photo-reduction efficiencies were observed in the photo-reduction of Pb2+ using 1% N-TiO2-PAN, 1% N-TiO2-PMAA-g-PVDF/PAN and 1% N-TiO2-PVDF membranes (90.5%, 88.9% and 86.9%, respectively) under similar conditions. Increasing the photo-catalyst loading to 3% N-TiO2 was observed to slightly increase the photo-reduction efficiency in the removal of Pb2+ unlike in the case of Fe3+. The best support material for the N-TiO2 photo-catalyst was PMAA-g-PVDF/PAN. [ABSTRACT FROM AUTHOR]

Radiant field distribution is an important modeling issue in many systems of practical interest, such as photo-bioreactors for algae growth and heterogeneous photo-catalytic reactors for water detoxification. In this work, a simple radiant field model suitable for dispersed systems showing particle size distributions, is proposed for both dilute and dense two-phase systems. Its main features are: (i) only physical, independently assessable parameters are involved and (ii) its simplicity allows a closed form solution, which makes it suitable for inclusion in a complete photo-reactor model, where also kinetic and fluid dynamic sub-models play a role. A similar model can be derived by making use of concepts developed in the realm of stereology. The resulting equation is similar, yet not identical, to that obtained with the probabilistic approach, due to the fact that in stereology the front plane, or the focus plane, may well cut through particles, a circumstance excluded both in the probabilistic model and in actual photoreactors. The two models are compared with pseudo-experimental data obtained by means of Monte Carlo simulations, and the probabilistic model is found to give rise to the best agreement. [ABSTRACT FROM AUTHOR]

2,4-Dichlorophenoxyacetic acid (2,4-D) is the third most commonly used herbicide all over the world. There is a contradicted opinion about its toxicity and its half life in the environment. In this study the most effective method of its degradation and bioremediation has been studied. Two microbial consortia capable of utilizing 2,4-D as a sole source of carbon were isolated from the Egyptian environment. One of the microbial consortia interestingly contained a certain kind of protozoa as one of the mixed consortia members. Degradation of 2,4-D by the microbial consortia was affected by 2,4-D initial concentration, agitation, pH of the medium and temperature. The two consortia were able to degrade up to 700 mg l −1 of 2,4-D. Pre-treatment with UV radiations in the presence of photocatalyst such as TiO 2 accelerates the biodegradation process. The toxic non biodegradable concentration of 2,4-D which was found to be the 800 mg l −1 , was degraded by pre-treatment with UV/TiO 2 and a subsequent microbial inoculation. The combined treatment proved to be an efficient mean of biodegradation and detoxification of toxic non biodegradable concentrations of 2,4-D. [ABSTRACT FROM AUTHOR]

Parchment is the support of several documents kept in libraries and archives all around the world. Much of this cultural heritage is rapidly degrading due to different causes, in particular fungi, with the risk of being lost. In recent decades new methods have been tried to improve the conservation, protection and usability of library and archive materials. In this work we showed a cleaning method of old documents in parchment bio-deteriorated by fungi. This method is easy, not expensive, and respectful of the document characteristics. In particular, it was evaluated the effectiveness of gellan gum and titanium dioxide nanoparticles hydrogels in cleaning and disinfecting parchment samples contaminated by Penicillium chrysogenum and Cladosporium cladosporioides , which are two fungi notorious for their attacks to parchment cultural heritage. Results showed that the mechanical soft action of gellan gum hydrogels combined with the photo-catalytic activity of titanium dioxide nanoparticles allow an important cleaning and disinfection of parchment with a consequent preservation from further fungal colonization of samples over long time when compared to untreated ones. [ABSTRACT FROM AUTHOR]

The aim of this research was to generate titania-embedded polythene (PE) material that is photo catalytically degradable and could also serve as a photocatalysis vehicle. Titania Nanoparticles (TNPs) prepared from General Purpose TiO 2 powder, by hydrothermal method and characterized by SEM, XRD and EDX, were used to prepare pure and titania embedded (0–20%) PE composite films. Photocatalytic degradation, separately under UV and visible light, of these films was monitored for a period of 90 days. PE film weight loss, due to degradation, under UV and visible light, was found to be 60% and 33% respectively. The film deterioration was confirmed by FTIR and SEM analysis. On the other hand, the potential of the degraded titania-PE material, to photo catalytically degrade a model pollutant, Drimarene Brilliant Red (DBR) dye, was examined. For this purpose, PE films having suffered around 50% weight loss were allowed to interact with DBR dye, in a batch mode, under UV and visible light. Compared to the fresh titania-embedded films, the degraded material showed a considerable activity as regards discoloration of the dye, following zero order kinetics. The novel photocatalyst (degraded titania embedded PE films) was recovered and reused for four cycles with minor loss of activity. [ABSTRACT FROM AUTHOR]

The adsorption of chemically similar but differently oxygen reactive phenolic-acid derivatives on the Ti-nanotubes (TiNTs) surfaces to increase and/or broaden their photo-induced activity was studied using Raman and X-ray photoelectron spectroscopies combined with zeta-potential analyses. Photo-catalytic activities and stabilities of newly synthesized particles were evaluated by using high-resolution capillary electrophoresis in combination with cyclic voltammetry and spin-trapping EPR spectroscopy. The modification with caffeic acid (CA) resulted in well-oriented and dense but oxygen semi-stable thin layer (1–3 nm) of self-assembled mono-molecular and/or bi-dentate coordinated molecules on the TiNTs’ surfaces, which narrowed the band gap from 2.9 eV (for un-modified TiNTs) to 1.55 eV, but however restrict the hydroxyl radicals generation under both UV (320 nm) and VIS (450 nm) source radiations. On the other hand, the gallic acid (GA) resulted in situ polymerized GA layer through bi-dentate binding as highly-oxygen-stabilized surface structure, yielding narrower band gap of 2.25 eV and increased hydroxyl radical’s generation under both exposure lights. The third tested hydroxybenzoic acid (HA), resulted to an unstable layer bonded thorough single-hydrogen bonding mechanism. This work offers a new modification strategy for stable (oxygen and photo-induction related) and highly visible–light responded TiNTs as photocatalyst. [ABSTRACT FROM AUTHOR]

The development of sunlight-activated and environmentally friendly photo-catalysts for wastewater treatment and air purification is an open scientific and technological challenge. In this regard, the present work reports on a Chemical Vapor Deposition route to phase-pure iron(III) oxide nanosystems [α-Fe2O3 (hematite) and β-Fe2O3 (bixbyite)]. The obtained polymorphs have been characterized in detail in their nanostructure, composition, morphology and optical properties. The synthesized supported Fe2O3 nanomaterials have also been tested in the photo-degradation of a model organic dye (methylene blue) in the liquid phase, as well as in the photo-oxidation of NO in air, both activated by simulated solar light. The obtained results, of interest for eventual use in water and air purification, are critically discussed as a function of nanosystem chemico-physical properties. [ABSTRACT FROM AUTHOR]

Generally cuprous oxide has higher photocatalytic activity in the visible region. It is widely applicable in the field of dye degradation. SrO/Cu2O nanocomposites were synthesized by sol-gel method and characterized using SEM, EDAX, AFM and particle size analyzer. SEM, EDAX, AFM and particle size analysis studies indicate that SrO/Cu2O composites are in nano-size range. The catalytic efficiency of nanocomposites was compared with commercial mixture of SrO/Cu2O photocatalyzed oxidation of diphenylamine (DPA) using UV light of wavelength 365 nm on SrO/Cu2O nanocomposites and SrO/Cu2O semiconductor mixture surfaces in ethanol yield N-phenyl-p-benzoquinonimine. The photocatalysis was examined as a function of (DPA), airflow rate and intensity of illumination. The photocatalytic studies revealed the sustainable photocatalytic efficiencies. The product formation was high with illumination at 254 nm than at 365 nm. Electron donors like triphenylphosphene, hydroquinone and tetraethylamine do not enhance the photo-oxidation. Both anionic and cationic surfactants favor photocatalysis. Vinyl monomers neither slowdown the photo-oxidation nor undergo polymerization. Singlet oxygen quencher azide ion does not suppress the photo-oxidation. Singlet oxygen generator enhances the photocatalysis. The catalytic efficiencies of nanocomposites were nearly four times higher than that of commercial mixture of SrO/Cu2O. [ABSTRACT FROM AUTHOR]

Highlights: [•] Kinetic analysis of CeO2-TiO2 materials in toluene and E. coli photo-elimination. [•] Modelling of chemical and biological degradation processes under UV and Visible light illumination. [•] The Ce-Ti systems outperforms titania (including P25) and ceria single oxide references. [•] The Ce-Ti system shows potential for general application in the elimination of pollutants. [Copyright &y& Elsevier]

Combined heterogeneous and homogenous photo-catalytic degradation of hospital wastewater was investigated. Three processes -- solar/TiO2/H2 O2, solar/Fe2+/H2O2 and solar/TiO2/Fe2+/H2 O2 -- were evaluated. The solar/TiO2 /Fe2+/H2O2 process displayed increased efficiency due to the synergetic effect of homogeneous and heterogeneous photo-catalytic reaction. The combination increased the photo process efficiency by decreasing the reaction time of the separate operations and decreased the cost of treatment. The optimal conditions enabling over 99% reduction of chemical oxygen demand (COD) were pH 7, 0.5 g/L Fe2+, 0.2 g/L TiO2 and 1.35 g/L H2O2. The effluent COD and total suspended solids concentrations were 20 and 30 mg/L, respectively, which met the discharge standard requirements. [ABSTRACT FROM AUTHOR]

In this review, we first discuss the photophysics reported in the literature for mononuclear ruthenium complexes bearing ligands with extended aromaticity such as dipyrido[3,2-a:2',3'-c]phenazine (DPPZ), tetrapyrido[3,2-a:2',3'-c:3'',2''-h:2''',3'''-j]- phenazine (TPPHZ), tetrapyrido[3,2-a:2',3'-c:3'',2''-h:2''',3'''-j]acridine (TPAC), 1,10- phenanthrolino[5,6-b]1,4,5,8,9,12-hexaazatriphenylene (PHEHAT) 9,11,20,22-tetraazatetrapyrido[ 3,2-a:2',3'-c:3'',2''-l:2''',3'''-n]pentacene (TATPP), etc. Photophysical properties of binuclear and polynuclear complexes based on these extended ligands are then reported. We finally develop the use of binuclear complexes with extended p-systems for applications such as photocatalysis. [ABSTRACT FROM AUTHOR]

Tamoxifen (TMX) is a low biodegradable non-steroidal tri-phenyl ethylene and is one of the most widely used anti-cancer drugs, which is used in various stages of treatment, inhibition, and prevention of breast cancer. TMX can end up in the water bodies in several ways such as hospital and domestic effluents, and excretion via urine and feces of the patients that use it. Among treatment methods, Advanced Oxidation processes (AOPs), photo-catalytic degradation as a practical way, is used to degrade TMX by producing nonselective free radicals (i.e. •OH). This study aimed to synthesize a novel FeCl 2 @AC@ZnO magnetic nano-composite and its efficiency for degradation of TMX as a low biodegradable carbohydrate. Artificial Neural Networks (ANN) was used to study sensitivity analysis of variables. The results of the characterization study indicated that FeCl 2 @AC@ZnO had average particle size of 56 nm, gap band ~ 3.0 and excellent morphology. According to the results, the degradation efficiency of TMX under pH 7, catalyst dose 0.005 g/L, initial concentration 10 mg/L reached 100% and the produced intermediated compounds were 2-methyl-3 H-imidazol-4-ol, 2-Oxopyrrolidin-1-yl) acetic Acid, 2-nitropropanoic-acid, 4-Heptanol, 2,4,6-trimethyl, and 3-Methyl-1-butanol. The result of sensitivity analysis revealed that the order of the parameters effect was as follow contact time ˃ pH ˃ concentration. Therefore, it can be concluded that the FeCl 2 @AC@ZnO magnetic nano-composite has a high photocatalytic activity and it can be used in full to degrade TMX from an aqueous solution. [Display omitted] • A novel FeCl 2 @AC@ZnO magnetic nano-composite was synthesized and characterized. • Tamoxifen (TMX) was completely removed under optimized photo-catalytic process. • Degradation of TMX followed pseudo-first-order kinetics. • ANN introduced contact time and pH as the most influential parameters. • The by-product formed were simple carbohydrates. [ABSTRACT FROM AUTHOR]