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Abstract Zinc Vanadate Zn 3 (VO 4) 2 nanoplates with width and thickness 300–500 nm and 50–75 nm diameter were synthesized by the facile modified hydrothermal method. Which containing mixing of Ammonia metavanadate (NH 4 VO 3) powder with zinc acetate (Zn(CH 3 COO) 2 ·2H 2 O), in the presence of CTAB and N, N-dimethyl formamide (DMF), the pH was adjusted around 5 and white precipitates were obtained. The potential of Zn 3 (VO 4) 2 photocatalyst was investigated by degrading Congo Red (CR) and Crystal Violet (CV) dyes using a UV–visible spectrophotometer. These Zinc vanadate nanoplates (ZnVO-Nps) showed enhanced dye removal (100%) due to reduced band gap 2.68eV and high surface area (84 m2/g). The Photoluminescence measurement showed the ZnVO-Nps potential for blue/green visible optical devices. These result showed that ZnVO-Nps have higher photocatalytic degradation due to the large surface area and porosity; it is proposed that the ZnVO-Nps demonstrated the high-level application for the degradation of organic pollutants under visible light irradiation. Graphical abstract Image 1 Highlights • First time Zn 3 (VO 4) 2 with nanoplates morphology reported for the degradation of dyes. • Zn 3 (VO 4) 2 nanoplates showed excellent visible light driven photocatalytic activity. • Crystal violet and Congo red dyes degraded within 60 and 150 mints, respectively. • Interface of catalyst and dye is a promising factor for photocatalytic degradation. • This method provides a simple and cost economical manufacturing process. [ABSTRACT FROM AUTHOR]

In this work, two new N-annulated perylene-based organic sensitizers ( PY-1 and PY-2 ) have been developed for dye-sensitized graphitic carbon nitride (g-C 3 N 4 ) to remarkably enhance photocatalytic hydrogen production under visible-light irradiation (420 nm ≤ λ ≤ 780 nm). The results showed that the H 2 production rates of the PY-1 /g-C 3 N 4 /Pt and PY-2 /g-C 3 N 4 /Pt were up to 5508.1 μmol h −1 g −1 and 11,855.4 μmol h −1 g −1 , respectively, which were 8.98 and 19.3 times higher than that of the g-C 3 N 4 /Pt, respectively. Specifically, an impressive record apparent quantum efficiency (AQY) of 27.16% for PY-2 /g-C 3 N 4 /Pt system was achieved at λ = 550 nm monochromatic light irradiation. Moreover, the formation of amide bonds between dye molecules and g-C 3 N 4 was firstly confirmed by FTIR spectrum and theoretical calculation. The amide bonds provided the electron transfer channels to significantly improve interface charge transfer and separation, thus resulting in a more efficient hydrogen production. More importantly, PY-1 /g-C 3 N 4 /Pt and PY-2 /g-C 3 N 4 /Pt displayed good stability under long-term irradiation and was favorable and significant for practical application. Our work indicated that dye sensitized g-C 3 N 4 to form an amide bond is a promising strategy to realize the effective conversion of solar energy to hydrogen energy through molecular engineering. [ABSTRACT FROM AUTHOR]

Abstract Photocatalysis, a green technique is widely applied in the fields of environmental remediation for the removal of many pollutant constituents. It is known that major problems related to the present photocatalytic system, which significantly limit their photocatalysis efficiency, are low-usage of visible light, fast recombination and also the low migration ability of the photo-generated electrons and holes. To solve the problem associated with conventional photocatalytic systems, recently hybrid photocatalysts containing carbon quantum dots (CQDs) have been proposed. The tunable photocatalytic characteristics of CQDs are widely mentioned. Moreover, the excellent photocatalytic activity of CQDs alone and in combination with photoactive species in the photo-degradation of organic pollutants was confirmed in the many reports. This work presents a comprehensive view of the application of CQDs to improve conventional photocatalytic systems in those studies which considered organic dyes as sample pollutants. In addition to providing detailed information regarding important roles of CQDs in photocatalytic activity enhancement, this review provides the comprehensive details about findings of the photocatalytic degradation of dyes using CQD-based photocatalysts and the best CQD-based composites photocatalysts are highlighted. Highlights • Combination of CQDs/conventional photo-catalysis systems improved their performance. • Multifunctional roles of CQD in photo-catalysis ate extensively elucidated. • CQD-based photo-catalysis degradation of organic dyes is comprehensively reviewed. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Vanadium oxide improved the photocatalytic activity of four different supports. • Brønsted acid sites concentration on V 2 O 5 /ZM5 and V 2 O 5 /TiO 2 is higher than V 2 O 5 /SBA. • Remarkable photocatalytic activity was observed on V 2 O 5 /ZM5 under visible light. • V4+ species and Brønsted acid sites improved the photocatalytic degradation of Eosin Y. • V 2 O 5 supported on TiO 2 and zeolite ZM5 are highly efficient to eliminate organic dye pollutants. Abstract SBA, zeolite-ZM5, TiO 2 and P25, used as dispersant agents of vanadium oxide, were synthesized. The supports (SBA, Zeolite-ZM5, TiO 2 and P25) were loaded with 3 wt.% of V 2 O 5. V 2 O 5 /ZM5, V 2 O 5 /P25 and V 2 O 5 /TiO 2 showed high photocatalytic activity for the degradation of Eosin Y employing a visible light source (450 nm). The photocatalysts were characterized by X-ray diffraction, XPS, UV-vis, S BET , SEM, TEM, and FTIR (surface acidity). Under visible light, the photocatalytic degradation rate displayed the following order V 2 O 5 /TiO 2 (93%) > V 2 O 5 /P25 (81%) > V 2 O 5 /ZM5 (70%) > V 2 O 5 /SBA (55%). This behavior is in conjunction attributable to the oxidation state of the vanadium species V4+ and the presence of Brønsted acid sites. The structure and properties of the TiO 2 play an important role during the photodegradation of the Eosin Y. Results here obtained give new insights for the water treatment processes using visible light over vanadium photocatalysts. [ABSTRACT FROM AUTHOR]

In this study ZnO/ZnS/CuS heterostructure have been controllably synthesized through a microwave-assisted synthesis and cation exchange. The compounds ZnO, ZnO/ZnS and ZnO/ZnS/CuS were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), ultravioletvisible (UV-vis) and Raman. It is found that the crystal structures obtained were Hexagonal Wurtzita for ZnO, hexagonal Wurtzita for ZnS, and hexagonal covellina for CuS. In comparison of ZnO and ZnO/ZnS the results show that ZnO/ZnS/CuS heterostructure has a higher photocatalytic activity under visible light, because its photocatalytic properties increase, helping to separate the electron-hole. These ZnO/ZnS/CuS efficiently decompose organic dyes such as methyl orange and methylene blue upon visible light conditions. Degradation rates can reach 31% and 71% during 240 min of treatment, respectively. The experiments revealed that the ZnO/ZnS/CuS decomposes methylene blue much faster than methyl orange. [ABSTRACT FROM AUTHOR]

• A 2D covalent organic framework Por-PD-COF as selective adsorbent and photocatalyst was designed and synthesized. • Por-PD-COF could selectively and competitively adsorb MB from the mixed organic dyes aqueous solution. • Por-PD-COF could photodegrade MB effectively under visible light. • Por-PD-COF can be recycled and reused after absorption or photocatalysis. In this work, amide bonds linked 2D porphyrin-based covalent organic framework (Por-PD-COF) was designed and synthesized through condensation reaction between meso -tetrakis (p -carboxyphenyl) porphyrin (TCPP) and para -phenylenediamine (PD). Large surface area, abundant active sites and good stability of Por-PD-COF made it can quickly and efficiently absorb methylene blue (MB) selectively and remove it from aqueous solution. More importantly, in different mixture of organic dyes including RhB and MB, MB and MO, Por-PD-COF can selectively adsorb MB with a large adsorption capacity (328.57 mg·g−1), while a little MO and hardly RhB because of the unique charge selectivity and specific pore size. Especially in the mixture solution of MO and MB, compatitive adsorption appeared, MB can substitute the adsorbed MO on the active sites in the channel of Por-PD-COF. Furthermore, with the band gap narrow to 1.02 eV, Por-PD-COF could be used as efficient photocatalyst to degrade MB (99%, 180 min) directly under visible light irradiation, and can be reused for four times with almost no absorptive and photocatalytic capacity losing. The possible adsorption and photocatalytic mechanisms of Por-PD-COF were also proposed. As a result, with the uncomplicated preparation, effective and selective adsorption and reusability, Por-PD-COF was a promising specific adsorbent and photocatalyst for further application in specific organic molecules separation and organic waste removal from aqueous solution. [ABSTRACT FROM AUTHOR]

Cerium oxide nanoparticles, synthesized by microwave mediated hydrothermal method, was characterized by using XRD, FT-IR, SEM, TEM, XPS, DR/UV–vis, and BET analyzer and applied for simultaneous adsorption/ photocatalytic decolourisation of two commonly used organic dyes namely Alizarin red S (ARS) and Eriochrome black-T (EBT). Powder XRD pattern coupled with SEM/TEM revealed the formation of single cubic phase spherical CeO 2 nanoparticles with average particle size of ∼15 nm. The sample showed moderate specific surface area (47.73 m 2  g −1 ) and relatively lower band gap (2.78 eV) than bulk CeO 2 . XPS study confirmed the existence of both Ce 4+ and Ce 3+ in the prepared sample. Batch adsorption studies without light irradiation showed significant adsorption of both the dyes on CeO 2 nanoparticles with monolayer adsorption capacity (Q o ) values 44.1 and 57.8 mg g −1 for ARS and EBT, respectively. Under visible light irradiation, the overall decolourisation (adsorption/photo-degradation) of both the dyes increased substantially and the optimum amount of CeO 2 required for complete decolourisation of ARS (100 mg L −1 ) was 0.80 g L −1 while relatively lesser dose of catalyst (0.60 g L −1 ) was required for the same concentration of EBT. Suitable mechanisms were proposed for the decolourisation of dyes under visible light based on GC–MS/LC–MS data of the degraded products/intermediates. [ABSTRACT FROM AUTHOR]

Bi2WO6 loaded g-C3N4 composites with excellent photocatalytic activity for degradation rhodamine B (RhB) and tetracycline hydrochloride (TCH) was successfully synthesized via a facile and high-yield solvothermal route. The results showed that well-crystallized Bi2WO6 particles were loaded on sheet-like g-C3N4 and formed the heterojunction by chemical change of C, N and O. It was showed that loading g-C3N4 improved the as-prepared composites to own more effective electrical conductivity and narrower band gap, which can enhance the separation and migration of photogenerated electron-holes as so to enhance the photocatalytic activity. Hence, Bi2WO6/g-C3N4 exhibited great photocatalytic activities for degradation of RhB (99.6%, 75 min) and TCH (73.0%, 105 min). In addition, it was determined that the optimal mass of g-C3N4 addition was 0.05 g. This work provided a high-efficiency principle method to synthesize Bi2WO6 loaded g-C3N4 composites with the excellent photocatalytic performance for actual produce. [ABSTRACT FROM AUTHOR]

In this work, for the first time, magnetic NiFe2O4@ZnO nanocomposite was synthesized using tragacanth gel by the novel sol-gel method. NiFe2O4@ZnO magnetic nanocomposite was investigated using powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), vibrating sample magnetometer (VSM), Transmission electron microscopy (TEM), Field emission scanning electron microscopy (FESEM) and energy dispersive X-ray analysis (EDX). The NiFe2O4@ZnO MNCs exhibit ferromagnetic behavior at room temperature, with a saturation magnetization of 15.22 emu/g and a coercivity of 150 Oe. XRD results show that NiFe2O4@ZnO nanocomposite corresponds to the hexagonal wurtzite of ZnO and the spinel cubic structure of NiFe2O4. The present magnetic nanocomposite displays high photocatalytic activity for the removal of direct blue 129 dye and reactive blue 21 dye under irradiation with visible light. The results demonstrated that the catalyst can degrade ca. 98% of the direct blue 129 and ca. 96% of the reactive blue 21 dyes. The current nanocomposite can be separated from the reaction mixture using an external permanent magnet and its high performance saved even after recycling fifth times. [ABSTRACT FROM AUTHOR]

Solvothermal reaction in tren/tatda mixed polyamines produced a transition metal (TM) thiostannate [Mn(tren)(H 2 O)][Mn(baen)] 3 Mn 4 Sn 6 S 20 ∙9H 2 O ( 1 ) containing a novel T3 supertetrahedral nanocluster [Mn 4 Sn 6 S 20 ] 8− . The T3 cluster was constructed by SnS 4 and MnS 4 tetrahedra via corner-sharing with the SnS 4 tetrahedra occupying four corners of the T3 cluster. It has different TM/Sn ratio from the traditional T3 cluster [TM 5 Sn 5 S 20 ] 10− (TM = Zn, Co) prepared by extraction method using alkali cations as the counter ions. Compound 1 is the first T3 cluster of the TM-Sn-Q phase prepared by solvothermal method and stabilized by TM-amino complex counter ions. The same solvothermal reaction with Se instead of S afforded a selenidostannate [Mn(baen)] 2 Sn 2 Se 6 ( 2 ) containing a dimeric [Sn 2 Se 6 ] 4− anion. Compound 1 exhibits selective photocatalysis in photodegradation of organic dyes. It has higher photocatalytic effect in the photodegradation of crystal violet (CV) than rhodamine B (RhB) under visible light irradiation at room temperature. [ABSTRACT FROM AUTHOR]

The photocatalytic activity of ZnO:Mo/GCN (ZnO:Molybdenum/g-C 3 N 4 ) thin films deposited using a simple cost-effective jet nebulizer spray pyrolysis technique with different Mo doping concentrations (1,2 and 3 at.%) was studied. The photocatalytic degradation test was carried out against Methylene blue (MB) and Rhodamine B (RhB) dyes under visible light. It is found that thin film of ZnO:Mo/GCN with 1 at.% of Mo exhibits superior photocatalytic efficiency compared with the other samples. The degradation rate constant of this sample is 0.0727 and 0.0268 min −1 for the tested MB and RhB dyes, respectively which are nearly two times and four times greater than the respective rate constant values of pristine ZnO. The mechanism involved in the enhanced photocatalytic activity is addressed with the help of obtained results. The properties of the deposited samples are correlated appropriately with the photocatalytic efficiency of the samples. The photostability of the prepared catalysts is tested experimentally. [ABSTRACT FROM AUTHOR]

Design and usage of efficient visible light photocatalytic systems for wastewater treatment and degradation of organic dyes are of remarkable interest in the fields of environmental protection. In this study, magnetic ZnFe 2 O 4 , ZnFe 2 O 4 /ZnO, Tannin/ZnFe 2 O 4 and Tannin/ZnFe 2 O 4 /ZnO nanocomposites with interfacial contact have been synthesized. The photocatalytic efficiencies of as-obtained samples are analyzed by the degradation of indigo carmine in aqueous solution under UV and visible-light. The degradation ratios of IC are 82% and 99% of IC over the Tannin/ZnFe 2 O 4 /ZnO under the both of UV light and visible light for 90 min, respectively. And after five times recycling, the photocatalytic performance of IC presence the Tannin/ZnFe 2 O 4 /ZnO can even reach nearly 89.79%. The results demonstrate that the Tannin/ZnFe 2 O 4 /ZnO exhibits great photocatalytic efficiency for indigo carmine (IC) compared to their constituent photocatalysts and easy separation from dye solution by magnet. The synergistic interactions between ZnFe 2 O 4 , tannin and ZnO prolonged lifetime of photoexcited carriers leading to greater absorption in both UV and visible light. This nanocomposite was beneficial for separating the photogenerated charge carriers and facilitating electron transfer. Tannin has a decisive role for increasing the photocatalytic performance of ZnFe 2 O 4 due to the abundant units of phenolic groups in tannin molecules. ZnFe 2 O 4 makes the Tannin/ZnFe 2 O 4 /ZnO magnetically separable in a system. This work presents new insights that tannin molecules function as great modifier to improve very impactful tannin-modified magnetic photocatalysts in removing environmental contamination. [ABSTRACT FROM AUTHOR]

A synthesis of aminothiazoles from various 1,3-dicarbonyls and thioureas without a leaving group has been developed. The reaction is photocatalyzed by tetraiodofluorescein, an organic dye. Under irradiation with green LEDs, a sulfur radical is generated in situ from thiourea, followed by addition to the enol tautomer, forming the aminothiazole backbone. This novel strategy provides a greener alternative to the traditional leaving group protocols, with excellent atom economy. [ABSTRACT FROM AUTHOR]

Photocatalytic degradation of organic dyes in wastewater using visible light illumination is a green technology which requires efficient visible-light driven active catalytic material. For this, we have reported a novel visible light active Eu/WO 3 system with variation in europium contents (0, 2%, 4% and 6% Eu), which demonstrated enhanced photocatalytic activity for the degradation of various organic dyes including methylene blue (MB), methyl orange ((MO) and rhodamine B (RhB). Scanning electron microscopy (SEM), X-ray diffractometer (XRD), energy dispersive X-ray (EDX), UV–visible spectroscopy and photoluminescence (PL) spectroscopy were used for the characterization of nanostructures. The results showed that Eu has effective role in modifying the structural, morphological and optical properties of WO 3 photocatalyst. Moreover, the photocatalytic performance of WO 3 was improved due to incorporation of Eu. From results, it was seen that photocatalytic activity increases with increasing Eu concentration upto 4%, however, further increase in Eu concentration (6%) has decreased the performance under these condition for all dyes. The enhanced photocatalytic efficiency could be attributed to suppressed recombination of charge carriers and enhanced visible light absorption and increased BET surface area due to Eu doping into WO 3 photocatalyst. The as-synthesized nanostructures will be considered as a promising photocatalytic materials for the future research in this field. [ABSTRACT FROM AUTHOR]

Titania (TiO2) is considered to have immense potential as a photocatalyst, the anatase phase in particular. There have been numerous attempts to push the limits of its catalytic activity to higher wavelengths to harness the visible electromagnetic radiation. Most of the investigations till date have been restricted to fine-tuning the bandgap by doping, control of defect chemistry at the surface and several to first principle simulations either with limited success or success at the cost of complexities in processing. Here, we report a simple and elegant way of preparing ceramics through precursor chemistry which involves synthesis of macroporous and mesoporous nanocomposites with in situ formation of TiO2 nanocrystals into a robust and protecting SiOC matrix. The in situ nanoscaled TiO2 is anatase of size 9-10 nm, which is uniformly distributed in an amorphous SiOC matrix forming a new generation of nanocomposites that combine the robustness, structural stability and durability of the SiOC matrix while achieving nanoscaled TiO2 functionalities. The stabilization of the anatase phase even at temperature as high as 1200 °C was evident. With an average pore size of 6.8 nm, surface area of 129 m²/g (BET) and pore volume of 0.22 cm³/g (BET), mesoporosity was achieved in the nanocomposites. The composites exhibited visible light photocatalytic activity, which is attributed to the Ti--O--C/TiC bonds resulting in the reduction of band gap by 0.2 to 0.9 eV. Furthermore, the heterojunction formed between the amorphous SiOC and crystalline TiO2 is also expected to minimize the recombination rate of electron-hole pair, making these novel nanocomposites based on TiO2 extremely active in visible wavelength regime. [ABSTRACT FROM AUTHOR]

The copper(II) coordination polymer [Cu 2 (bix)(sdc) 2 ] n ( 1 ) was synthesized by the hydrothermal method (bix = 1,4-bis(2-methyl-imidazol-1-ylmethyl)benzene, sdc = 2,5-thiophenedicarboxylate). The copper(II) atom of 1 shows unsaturated square-pyramidal configuration. 1 exhibits the 2-fold interpenetrating three-dimensional pcu network based on the [Cu 2 (COO) 4 ] dimers. 1 is an efficient and universal photocatalyst for the degradation of the organic dyes methylene blue (MB), rhodamine B (RhB) and methyl orange (MO) under visible light irradiation, and is very stable and can be reused. [ABSTRACT FROM AUTHOR]

Synthesis and characterization of the pristine NiO, Bi 2 O 3 and composite NiO–Bi 2 O 3 (NBO) nano material systems with the modified surface morphology is reported. The NBO and pure oxide materials are thoroughly characterized with various spectroscopic methods such as XPS, p-XRD, FTIR, Raman, UV–vis-DRS, PL, FESEM and HRTEM analysis. XRD results showed the formation of a new γ-phase of Bi 2 O 3 after incorporating Ni on its surface. XPS and EDX analysis confirmed the presence of both Ni2+ and Bi3+ in the nanoparticles. HRTEM analysis showed NiO nanospheres on Bi 2 O 3 nanorods with 13–18 nm nanoparticle sizes Furthermore, as a result of composite phase formation, a substantial decrease in bandgap from 3.28 to 2.62 eV is found, which was captivating to study the visible light energy induced photodegradation of methylene blue (MB), methyl orange (MO) dyes and agricultural soil pollutants (ASP). The effect of pH, dosage, and scavenger's studies are investigated to establish the mechanism of the active species of the photodegradation process and which is supported by photocurrent and EIS studies. Under the optimal framework, the photocatalytic degradation efficacy of the MB, MO dyes and ASP degradation with NBO was 95, 90 and 94% respectively. Additionally, HPLC analysis of initial and final samples of dyes was studied and TOC analysis for ASP examined. NBO catalyst was recovered and reused umpteen times with marginal change in photocatalytic efficiency. NBO nano composite material act as photocatalyst for photodegradation of MB and MO dyes and agricultural soil pollutants under visible light treatment because of electron-hole pair recombination is low. [Display omitted] • Preparation of pure NiO, Bi 2 O 3 and new NiO–Bi 2 O 3 composite nanomaterials by wet-impregnation method and thoroughly characterized. • Photodegradation of organic dye pollutants such as methylene blue, methyl orange under visible light irradiation. • Photodegradation of agricultural soil pollutants was investigated and identified with LC-MS data. • Mechanistic studies established that the active species are hydroxy radials via several foragers studies. [ABSTRACT FROM AUTHOR]

Heterojunction with nano-level interfacial contact has an advantage in improving the transfer capacity of photongenerated carriers. In consequence, a heterojunction composite with nano-level interfacial contact was developed by establishing CdSe/Al 2 TiO 5 heterojunction composites. The heterojunction composite was established by combining Al 2 TiO 5 and CdSe nanocrystals. They provided superior nano-level interfacial contact. The photocatalytic activity of heterojunction composites were illustrated to be significantly improved compared to that of pure Al 2 TiO 5 and CdSe nanocrystals. Moreover, the photocurrent intensity of heterojunction composites displays a several times enhancement, implying the promotion of photocatalytic activity was owned to the nano-level interfacial contact with ideal photogenerated electron-hole pairs transfer behavior. [ABSTRACT FROM AUTHOR]

The microwave-assisted synthesis of graphene-Bi8La10O27-Zeolite (G-Bi8La10O27-Z) nanocomposite is reported here for the first time. In this investigation, a novel route is taken for the synthesis, interaction, kinetics, and mechanism of a hybrid G-Bi8La10O27-Z nanocomposite using a microwave-assisted method. The photocatalytic activities of the as-obtained catalysts were assessed based on the degradation of Rhodamine B (RhB), Methylene Blue (MB), and Texbrite (TXB) under visible light irradiation. The results show that the G-Bi8La10O27-Z nanocomposite exhibited more stable photoresponse degradation performance under the Visible light radiation than pure G-Bi8La10O27-Z; and that the synthesized G-Bi8La10O27-Z can be used as a high performance catalyst for dye wastewater. The detailed photocatalytic mechanism of the photodegradation process is also discussed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ag 6 Mo 10 O 33 /g-C 3 N 4 1D-2D heterojunction was prepared via chemical deposition. • Ag 6 Mo 10 O 33 /g-C 3 N 4 consists of Ag 6 Mo 10 O 33 nanowires and g-C 3 N 4 nanosheets. • It is highly efficient for degradation of organic dyes under visible light. • Superoxide radical anions and photogenerated holes are main active species. The construction of heterojunctions is an effective way to improve the activity of photocatalysts. Most heterojunction photocatalysts are portrayed by the deposition of semiconductor nanoparticles on other semiconductor supports (often 3D particles or 2D sheets), but 1D-2D hybridized heterojunctions portrayed by the supporting of semiconductor nanowires onto semiconductor nanosheets are rare. Herein, we report a novel Ag 6 Mo 10 O 33 /g-C 3 N 4 1D-2D hybridized heterojunction with highly enhanced visible-light-driven photocatalytic activity. Ag 6 Mo 10 O 33 nanowires were in situ loaded onto g-C 3 N 4 nanosheets by controlling the pH value (∼2) of the synthesis mixture. The resulting Ag 6 Mo 10 O 33 /g-C 3 N 4 heterojunction was found to be much more active than pristine Ag 6 Mo 10 O 33 , g-C 3 N 4 , or a mechanical mixture of both in the photocatalytic degradation of methyl orange (MO), Rhodamine B (RhB), and methylene blue (MB) under visible light irradiation. Through relevant characterization, the high activity of Ag 6 Mo 10 O 33 /g-C 3 N 4 heterojunction was mainly attributed to the efficient separation of photogenerated charge carries. Superoxide radical anions (O 2 −) and photogenerated holes (h+) were found to be the main active species. [ABSTRACT FROM AUTHOR]

The organic-dye-catalyzed visible-light-induced iodoperfluoroalkylation of unactivated terminal alkenes and alkynes was explored. This process was found to be effective for the simultaneous introduction of iodide and various perfluoroalkyl groups (including difluoroacetate) to alkenes and alkynes possessing a variety of functional groups. A possible reaction mechanism is proposed. This reaction provides a new, metal-free, green method for the synthesis of perfluoroalkylated compounds. [ABSTRACT FROM AUTHOR]

Herein, we demonstrate a facile way of fabricating visible-light-active lanthanum and nitrogen – co-doped SrTiO 3 – TiO 2 heterostructured macroporous monolithic materials with bicontinuous morphology by impregnating strontium and lanthanum ions into a preformed porous TiO 2 gel in aqeuous solution containing urea followed by heat treatment in NH 3 atmosphere. The SrTiO 3 macroporous monolithic materials were formed by a solid-state reaction between the TiO 2 gel phase and precipitated SrCO 3 , while Sr 2+ was partially substituted with La 3+ ions. The SrCO 3 was precipitated within the TiO 2 wet gel by the reaction between impregnated Sr 2+ and CO 2 , which was produced by hydrolysis and decarbonation of a chelating agent in the TiO 2 wet gels and by hydrolysis of urea at 60 °C. X-ray powder diffraction studies showed that the incorporation of strontium, lanthanum, and nitrogen could effectively retard the phase transformation of TiO 2 from anatase to rutile and growth of crystallites. XPS analysis confirmed that lanthanum atoms were incorporated into the SrTiO 3 lattice by substituting strontium atoms, and nitrogen was incorporated in the TiO 2 lattice (i) substitutionally forming Ti – N-bonds and (ii) interstitially. The resultant lanthanum and nitrogen – co-doped SrTiO 3 - TiO 2 heterostructured monolithic materials retained a narrow macropore size distribution at the diameter ∼1.7 μ m. [ABSTRACT FROM AUTHOR]

Metal organic frameworks (MOFs), a new class of porous crystalline materials have attracted attention because of potential applications in environmental remediation. In this work, an Fe-based MOF, FeBTC (BTC = 1,3,5-tricarboxylic acid), was successfully modified with Amberlite IRA-200 resin to yield a novel heterogeneous photocatalyst, A@FeBTC. The modification resulted in higher photocatalytic activity than FeBTC under the same conditions. After 60 min of visible light illumination (λ ≥ 420 nm) 99% of rhodamine B was degraded. The modification lowers the zeta potential, enhancing charge-based selective adsorption and subsequent photocatalytic degradation of cationic dye pollutants. The composite also improved catalyst stability and recyclability by significantly reducing loss of iron leaching. Photoluminescence studies show that introduction of the resin reduces the recombination rate of photogenerated charge carriers thereby improving the photocatalytic activity of the composite. Finally, a plausible photocatalytic reaction mechanism is proposed. [ABSTRACT FROM AUTHOR]

Photodegradation of organic pollutants using metal oxides has shown extraordinary promise owing to the catalytic efficacy, low cost, less noxiousness, and good chemical constancy. In this research, pure and transition metal ions (Cu)-doped V 2 O 5 nanosheets were synthesized and investigated for their photocatalytic efficiency using methyl blue (MB) and rhodamine B (RhB) organic dye pollutants under visible light irradiation. The orthorhombic crystal phase was confirmed by XRD analysis, which exhibited a stable phase upon incorporating Cu dopant ions. Optical properties were examined using optical absorption spectroscopy, while a reduced band gap was observed in the doped V 2 O 5 nanosheets over the undoped sample. EIS analysis confirmed lower charge resistance in doped V 2 O 5 nanosheets. The Cu dopant incorporation into the host matrix considerably enhanced photodegradation efficiency for MB and RhB impurities under light illumination. The improvement in catalytic efficacy is attributed to dopant ions that can separate photoinduced charge carriers and the quick movement of the charge. Moreover, comparatively lesser crystalline size, improved specific surface area, and hydroxyl group onto the catalyst surface are quite advantageous to offer better photocatalytic activity of Cu-doped V 2 O 5 nanosheets. [Display omitted] • Pure and Cu-doped V 2 O 5 nanosheets were synthesized using hydrothermal method. • XRD analysis confirmed orthorhombic crystal phase of synthesized materials. • Photodegradation of MB and RhB pollutants were examined under visible light. • Doped V 2 O 5 catalyst shows 95.4% and 91.2% degradation of MB and RhB. • · O 2 −, OH · species played a major contribution in the removal toxic pollutants. [ABSTRACT FROM AUTHOR]

Hierarchical Ag 2 CO 3 /Bi 2 O 2 CO 3 microflowers were synthesized at room temperature using a facile solution method. The as-prepared composite was composed of numerous two-dimensional nanosheets with oriented terminal arrangement. The photocatalytic activities of Bi 2 O 2 CO 3 , Ag 2 CO 3 and Ag 2 CO 3 /Bi 2 O 2 CO 3 were evaluated through the photodegradation of wastewater which contains organic dyes of rhodamine B (RhB), methyl orange (MO), methylene blue (MB), or their mixture under visible light irradiation (λ ≥ 420 nm). Results showed that the photocatalytic activity of Ag2CO3/Bi2O2CO3 was much higher than that of single phase Bi2O2CO3 or Ag2CO3. In addition, the Ag2CO3/Bi2O2CO3 photocatalyst also showed good photostability and recyclability. The excellent photocatalytic efficiency of the Ag2CO3/Bi2O2CO3 photocatalyst could be ascribed to the improved light absorption ability and the reduced recombination of photo-generated electron-hole pairs during photocatalytic reactions. Moreover, the possible transferred and separated behavior of electron-hole pairs and photocatalytic reaction mechanism on the Ag2CO3/Bi2O2CO3 photacatalyst are illustrated in detail. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) are considered as suitable materials for various applications in the area of photocatalysis. On the other hand, 2D BiOBr materials are efficient for the photodegradation of organic dyes under visible light illumination. In this work, BiOBr/NH2-MIL-125(Ti) composite photocatalysts with different NH2-MIL-125(Ti) content were prepared by incorporating NH2-MIL-125(Ti) with BiOBr using a co-precipitation method. A series of characterizations confirmed the strong synergistic effect between BiOBr and NH2-MIL-125(Ti). In rhodamine B (RhB) degradation experiments, the composite photocatalyst with a mass percent of 7 wt% NH2-MIL-125(Ti) exhibited an improved photocatalytic activity compared to pristine BiOBr and NH2-MIL-125(Ti). Furthermore, the enhanced photocatalytic performance under visible light illumination could be attributed to the Ti3+–Ti4+ intervalence electron transfer and synergistic effect between NH2-MIL-125(Ti) and BiOBr, and also resulted in a separation efficiency of photo-generated electron–hole pairs during the photocatalytic reaction. This study can open up numerous opportunities for the development of various MOF-based visible light photocatalysts when combined with 2D bismuth oxyhalide materials for applications in environmental cleaning. [ABSTRACT FROM AUTHOR]

The present work demonstrates a facile hydrothermal synthesis of Plasmonic Au–TiO 2 nanocatalyst followed by its successful application for complete photocatalytic dye degradation (oxidation) in batch and continuous flow process under natural sunlight as well as visible and UV light. The Au-TiO 2 nanocatalyst was synthesized by a hydrothermal method at basic pH conditions. It was meticulously analyzed by a variety of spectroscopic (UV-Vis, Raman, FTIR, PL, Powder XRD, ED-XRF, XPS), microscopic (FE-SEM with elemental mapping, TEM), and thermal (DSC) techniques. The characterization results showed that monodisperse Plasmonic Au(0) nanoparticles with a mean diameter of 12 ± 1 nm are homogeneously deposited on Anatase TiO 2 crystals. The nanocatalyst showed complete photocatalytic degradation of various dye compounds (Eosin Yellowish, Indigo Carmine, Methyl Orange, Methylene Blue, and Rhodamine B) under visible light or sunlight as confirmed through UV-Vis spectra, mass spectral study, and TOC analysis of dye solutions. A continuous flow process using a specially designed photoreactor was accomplished with a long catalyst lifespan, easy processibility, and low cost. Easy synthesis of the catalyst, its very detailed characterization, and its efficient catalytic studies to completely degrade various dye molecules under visible light source in the absence of any added oxidizer (O 2 , H 2 O 2 , KMnO 4 , Organic peroxides) and the demonstration of continuous flow process are significant highlights of the present work. A plausible mechanistic pathway is also presented in line with the previous literature reports and presently observed phenomenon. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel (1 T/2H)-MoS 2 /CoFe 2 O 4 heterojunction was successfully constructed. • Sample MC-2 exhibits the best photocatalytic activity. • The remarkable ferromagnetic property ensures it easy to be separated. • A feasible photocatalytic mechanism is proposed by the analyses on the energy bands and the trapping experiments of active species. The formation of heterostructures is an effective way to tune the band structure and photocatalytic property. Herein, an efficient (1T/2H)-MoS 2 /CoFe 2 O 4 heterojunction was prepared via a facile green hydrothermal method and performed well in the photocatalytic removal of organic dyes. By varying the molar ratio of MoS 2 versus CoFe 2 O 4 , the photogenerated electron-hole separation can be enhanced in the heterojunction. The MoS 2 /CoFe 2 O 4 composite with a 2:1 M ratio of MoS 2 to CoFe 2 O 4 (MC-2) shows the best photocatalytic performance, where 91.9 % of methyl blue (MB) is degraded within 60 min and its apparent rate constant is 5.94 and 25.43 times higher than those of pure MoS 2 and CoFe 2 O 4. In addition, MC-2 maintains high photocatalytic performance even in an aqueous environment similar to wastewater, where some different inorganic ions (e.g. , NO 3 –, CO 3 2– and SO 4 2–) are present. Further, the remarkable ferromagnetic property of MC-2 at room temperature ensures that the composites were easy to be separated from the wastewater. Meanwhile, the as-synthesized composites exhibit good reusability. A possible mechanism for photodegradation of MB is proposed for (1T/2H)-MoS 2 /CoFe 2 O 4 heterojunction by the analyses of the energy bands and the trapping experiments of active species. [ABSTRACT FROM AUTHOR]

[Display omitted] • MOF materials such as NH 2 -UiO-66 was decorated for the first time with FeOOH QDs. • The prepared NH 2 -UiO-66/FeOOH QDs photocatalyst was used for water remediation. • Photo-Fenton activity of photocatalyst was found greater than individual MOF and QDs. • Transfer of photo-excited e- from MOF to FeOOH QDs resulted to charge separation. • Both h+ and •OH were responsible for efficient degradation of pollutants. Coupling of inexpensive and easily synthesized FeOOH quantum dots (QDs) with metal–organic frameworks (MOFs) is an outstanding subject in photocatalysis field, which no research works have been reported in this regard so far. For this purpose, a novel photocatalyst was prepared by in-situ formation of different amounts of FeOOH QDs (5, 10 and 15 wt%) in the presence of NH 2 -UiO-66 as visible light-harvesting MOF. HR-TEM analysis revealed uniform decoration of NH 2 -UiO-66 with 2–5 nm sized FeOOH QDs. Photo-Fenton behavior of the resulted NH 2 -UiO-66/FeOOH(10 %) composite in the degradation of methyl violet (MV) was found to be higher than other composites with different loadings of FeOOH QDs. The effect of H 2 O 2 and photocatalyst dosage were also investigated and the best degradation efficiency of 82.2 % was achieved at optimal reaction conditions. It was observed that both FeOOH QDs and NH 2 -UiO-66 demonstrated poor photocatalytic activity individually, but their composite resulted in outstanding photo-Fenton activity because of effective electron transfer from photo-excited NH 2 -UiO-66 to FeOOH QDs. Scavenging experiments indicated that hydroxyl radicals and photo-generated hole are the main species responsible for photo-Fenton degradation of water contaminants. [ABSTRACT FROM AUTHOR]

Photocatalysis can be a potential technique for decomposing antibiotics contaminants from water. In this study, g-C 3 N 4 modified Bi/BiOBr nanosphere were prepared by a simple microwave solvothermal method, and the structure-properties relationships of the Z-scheme heterojunction were evaluated in degrading organic dyes. Various characterization techniques were then applied to elucidate the structure-performance relationships of the resulting heterojunction photocatalysts in degrading CIP. Compared with pristine g-C 3 N 4 or Bi/BiOBr, the g-C 3 N 4 @Bi/BiOBr nanocomposites showed heightened property in photocatalytic degradation of CIP. The photocatalytic efficiency of CIP decomposition over the Z-scheme of g-C 3 N 4 @Bi/BiOBr heterojunction was about 2.38 and 1.35 times homologous to those of original g-C 3 N 4 and Bi/BiOBr. The enhancement in photocatalytic activity of g-C 3 N 4 @Bi/BiOBr could be described by the Z-scheme pathway and the SPR effect of Bi0, which broadened visible light absorption and promoted the separation of photoinduced carriers. In addition, the effect of typical water matrix factors, such as pH, anionic, and cationic on photodegradation rate were evaluated. Furthermore, results of scavenging experiments showed that ·OH, ·O 2 −, and h+ all participate in the degradation of CIP. Based on the band structure and scavenging measurements, a possible photocatalytic mechanism for the as-synthesized g-C 3 N 4 @Bi/BiOBr composites was proposed. • Prepared g-C 3 N 4 @Bi/BiOBr composites by one-step microwave solvothermal method. • The introduction of g-C 3 N 4 effectively improved the separation of photogenerated carriers. • The high concentration of H+ inhibits the formation of ·O 2 −. Zn2+ and CO 3 2− inhibit the photocatalytic process most. • The ternary composites showed good practicability under sunlight. A reasonable photocatalytic mechanism was proposed. [ABSTRACT FROM AUTHOR]

Photocatalysis is one of the effective methods to alleviate the urgent pressure on energy shortage and environmental pollution in modern world, for which TiO 2 has attracted great attention due to its excellent photocatalytic activity, high stability, non-toxicity and low cost. However, the wide band gap (about 3.2 eV), easy recombination between photogenerated electrons and holes, as well as easy agglomeration and difficult recycling of traditional nanomaterials limit its wide application. Herein, novel (N,F)-co-doped TiO 2-δ nanofibers were successfully prepared simply by thermally treating electrospun nanofibers under Ar atmosphere using polyacrylonitrile as the reductive agent, tetrabutyl titanate as the titanium source and trifluoroacetic acid as the fluorine source. The resultant product can be directly used as photocatalysts for degrading environmental pollutants, which can remove 27.2% of rhodamine B, 40.9% of methylene blue and 31% of Cr(VI) within 60 min under visible light irradiation from a 5 W LED lamp, being almost 11.8, 3.2 and 2.8 times those over its commercially available TiO 2 counterpart, respectively. The present work will provide a simple strategy to feasibly prepare various high-performance photocatalysts. [Display omitted] • Novel (N,F)-co-doped TiO 2-δ nanofibers. • Facile and highly efficient synthesis method based on electrospinning. • High efficient solar-driven photocatalysts for environmental remediation. • Mechanism for improved photocatalytic activity. [ABSTRACT FROM AUTHOR]

Selective functionalization of C(sp 3 ) H bonds is one of the final frontiers of synthetic chemistry. The employment of organic dyes (ODs) as visible light photocatalysts to approach these reactions has been of current interest mainly due to their lower cost and the avoidance of toxic heavy metals. In this digest, we outline the recent advances in organic dye-catalyzed C(sp 3 ) H functionalization reactions. [ABSTRACT FROM AUTHOR]

To design and synthesise highly efficient photocatalysts by a facile, environmental friendly, and economical method has become of vital importance in the photocatalytic field. With the assistance of a simple microwave treatment for 40 min, the reduced graphene oxide/Ag3PO4 (rGO/Ag3PO4) visible-light-response photocatalyst can be rapidly synthesized under the atmosphere. TEM results show that the irregular Ag3PO4 particles are distributed on the surface of the rGO sheet. In the photo-degradation process of methyl orange (MO), the optimum photocatalytic activity of rGO (1.5%)/Ag3PO4 under simulated daylight is almost 2 times higher than pure Ag3PO4. Obviously, this facile method paves a convenient way to prepare visible-light-response Ag3PO4-based composites with high photocatalytic efficiency in a large scale and also to reduce the high cost of Ag3PO4 for practical uses. [ABSTRACT FROM AUTHOR]

Electrospun cellulose acetate (CA) membrane was employed as a support that provided sites for AgCl crystals in situ growth. The Ag@AgCl crystals on electrospun CA composites with exposed {1 0 0} and {1 1 1} facets were fabricated at room temperature by a double diffusion technique. The crystal structure, morphology, composition, and absorption light ability of CA supported Ag@AgCl were characterized utilizing X-ray powder diffraction (XRD), scanning electron microscopy (SEM), attenuated total reflection-infrared intensity (ATR-IR), X-ray photoelectron spectroscopy measurements (XPS), energy dispersive spectrometer (EDS) and ultraviolet–visible (UV–vis) diffuse reflectance spectra, respectively. The photocatalytic activity of the catalysts was evaluated using methyl orange (MO) as a target. The CA supported cubic Ag@AgCl catalyst exhibited much higher catalytic activity than octahedral catalyst in terms of the degradation of MO under visible light. The 10 mg CA based cubes could completely degrade MO (10 mg L −1 ) in 160 min. The photocatalyst still exhibited a good catalytic ability after three times. [ABSTRACT FROM AUTHOR]

A series of BiOCl x I y solid solutions with bifunctional properties was prepared by a hydrolysis method. When used as potential adsorbents for removal of dyes in wastewater, the as prepared samples exhibited the excellent adsorption and photocatalytic abilities, which indicated that the removal ability had been restored completely without centrifugal separating or other chemical desorption methods. Especially to the sample 301 prepared with a 3:1 M ratio of Cl to I, its adsorption capacity could reach nearly 5.0 mg g −1 within 5 min, which was at least 3 times larger than that of the individual BiOX (ca. 1.3 mg g −1 ), and its degradation efficiency of high concentration (20 mg L −1 ) methyl orange (MO) was up to 100% after 50 min of visible light irradiation. The relevant characterization results revealed that not only high specific surface area but also the electron structure of interlayer could be the key factors for the high adsorption ability. The possible mechanism was also discussed. [ABSTRACT FROM AUTHOR]

A series of 2D layered isostructural coordination complexes {[M3(L)2(H2O)6]·H2O}n (M = Mn (1), Mn0.7Co0.3 (2), Mn0.5Co0.5 (3), Mn0.3Co0.7 (4), and Co (5), respectively, H3L = 1-aminobenzene-3,4,5-tricarboxylic acid) have been synthesized under hydrothermal conditions, and applied to catalyze the reaction of degenerating organic dyes under visible light irradiation. The photocatalytic results indicate that complex 5 exhibits good photocatalytic properties in the presence of H2O2, while 1 can restrain the photodegradation of organic dyes. Remarkably, when Mn ions are gradually replaced by Co ions in the complexes, the photocatalytic activities of 1–5 turn from inhibition to promotion, which is a controllable regulation of photocatalytic properties via changing metal ions. Moreover, by using novel magnetic analysis methods and diffuse-reflectance UV/Vis spectra analysis methods, we explain the influence of central metal ions on the photocatalytic performance. [ABSTRACT FROM AUTHOR]

Novel reduced graphene oxide (RGO) enwrapped AgI nanocomposites were successfully fabricated by a facile template-free ultrasound-assisted method at room temperature. The structural, morphological, and optical studies demonstrate that the obtained nanostructures have good crystallinity and that the graphene nanosheets are decorated densely with AgI nanostructures. The photocatalytic activity of the composite was evaluated by the degradation of an organic dye, Rhodamine B (RhB), under visible-light irradiation. The results indicate that AgI with incorporated graphene exhibited much higher photocatalytic activity than the pure AgI due to the improved separation efficiency of the photogenerated carriers and that it prolonged the lifetime of the electron–hole pairs due to the chemical bonding between AgI and graphene. AgI (0.4 mg mL −1 of graphene oxide) nanocomposites displayed the highest photocatalytic degradation efficiency and the corresponding catalytic efficiencies within 70 min were ∼96%. Moreover, with the assistance of H 2 O 2 the photocatalytic ability of the as-obtained AgI-RGO nanocomposites was enhanced. The corresponding catalytic efficiencies within 30 min were ∼96.8% (for 1 mL H 2 O 2 ) under the same irradiation conditions. The excellent visible-light photocatalytic efficiency and luminescence properties make the AgI-RGO nanocomposites promising candidates for the removal of organic dyes for water purification and enable their application in near-UV white LEDs. [ABSTRACT FROM AUTHOR]

A series of Sn(Nb 1− x Ta x ) 2 O 6 solid solutions were successfully synthesized as novel visible-light-active photocatalysts. The characterizations of powder X-ray diffraction and UV–vis absorption spectrum indicate that these solid solutions possess continuous changes in the crystallography features and optical band gaps, and are therefore a group of continuous solid solutions. Their photocatalytic properties were evaluated via methylene blue (MB) photodegradation. The Sn(Nb 0.8 Ta 0.2 ) 2 O 6 sample showed the best photocatalytic performance, full mineralization ability, and an excellent stability. After 120 min of irradiation, the degradation and mineralization percentages of MB over Sn(Nb 0.8 Ta 0.2 ) 2 O 6 reached 99.5% and 98.9%, respectively; in addition, the degradation ratio remained at 97% after five-cyclic test. The further study on the active species and the theoretical calculation based on density functional theory helped to clarify the mechanism of the photodegradation reaction. On this basis, we propose the strategies to design high-performance photocatalysts employed in hole-dominated and electron-dominated photocatalytic applications, respectively. [ABSTRACT FROM AUTHOR]

Stolzite polymorph of PbWO 4 catalyst was prepared by the facile room temperature precipitation method. Structural parameters were refined by the Rietveld analysis using powder X-ray data. PbWO 4 was crystallized in the scheelite-type tetragonal structure with space group I4 1 / a (No. 88). Field emission scanning electron microscopy revealed leaf like morphology. Photoluminescence spectra exhibit broad blue emission (425 nm) under the excitation of 356 nm. The photocatalytic degradation of Methylene blue, Rhodamine B and Methyl orange dyes were measured under visible illumination. The 100% dye degradation was observed for MB and RhB dyes within 60 and 105 min. The rate constant was found to be in the decreasing order of MB > RhB > MO which followed the 1st order kinetic mechanism. Therefore, PbWO 4 can be a potential candidate for blue component in white LEDs and also acts as a catalyst for the treatment of toxic and non-biodegradable organic pollutants in water. [ABSTRACT FROM AUTHOR]

We synthesized Cu2O/BiVO4 composites by growing Cu2O nanoparticles on BiVO4 under mild condition. The optimized composite shows high photocatalytic efficiency in the simultaneous oxidation of organic dyes and reduction of Cr(VI) in neutral media. The XPS results confirm that the Cr(VI) adsorbed on Cu2O/BiVO4 was completely reduced to Cr(III). The photocatalyst can be used for the degradation of cationic or anionic dyes as well as a mixture of them under visible light irradiation. The photocatalytic activity of the composite can be ascribed to the heterojunctions between Cu2O and BiVO4, which facilitate the separation of photogenerated electrons and holes. The work demonstrates that the as-synthesized Cu2O/BiVO4 composite is a promising photocatalyst for the treatment of wastewater that contains organic dyes and Cr(VI) ions. [ABSTRACT FROM AUTHOR]

Pure and Eu-doped ZnO nanostructures with different amounts of Eu were synthesized using a simple sonochemical method. The as-synthesized samples were characterized by X-ray diffraction, scanning electron microscopy, UV–Vis spectroscopy, Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. The photocatalytic activity of as-prepared Eu-doped ZnO was investigated based on the decolorization of Acid Red 17 (AR17) under visible light irradiation. The decolorization efficiency was found to be 25.2%, 55.6%, 63.1% and 30.3% for undoped, 1% Eu-ZnO, 3% Eu-ZnO and 5% Eu-ZnO, respectively. Using 3% Eu-doped ZnO nanoparticles, the decolorization efficiency reached 100% by adding 0.1 mM S 2 O 8 2− . Response surface methodology based on five-level central composite design was applied to model and optimize the decolorization of AR17 over 3% Eu-doped ZnO/S 2 O 8 2− . Accordingly, the value of correlation coefficients ( R 2 = 0.970 and adjusted- R 2 = 0.935) obtained from analysis of variance confirmed the adequacy of fitted model. The maximum decolorization efficiency of 99% was achieved at an initial dye concentration of 5 mg/L, catalyst dosage of 1.25 g/L, S 2 O 8 2− concentration of 0.25 mM and reaction time of 150 min. The decolorization efficiency decreased only 7% after 4 repeated runs. [ABSTRACT FROM AUTHOR]

Adopting a facile one-step solvothermal method, CN/MgAl 0.80 Ce 0.20 -LDH, a lamellate composite of graphitic carbon nitride (g-C 3 N 4 , CN) and Ce-doped MgAl-layered double hydroxide (LDH), was synthesized. Profiting from the combined effect of Ce-doping and CN-LDH composition, CN/MgAl 0.80 Ce 0.20 -LDH possesses large specific surface area (52.71 m2 g−1) and high separation efficiency of photogenerated charge. When used to remove organic dye Congo red (CR), the composite exhibits enhanced efficiency which can be attributed to the synergetic performance of adsorption and photocatalysis. As a result, ~49% CR (50 mg L−1) can be adsorbed by CN/MgAl 0.80 Ce 0.20 -LDH and the CR degradation efficiency exceeds 90% within 180 min under light-emitting diode (LED) visible light irradiation, which is much higher than that of pristine CN (48.77%). The augmented surface area and proliferated active sites benefit the increase of adsorption capacity. The enhanced photocatalytic performance can be attributed to the efficient transmission of photogenerated electrons and holes between CN and MgAl 0.80 Ce 0.20 -LDH. Electrochemical impedance spectroscopy (EIS) analysis and photoluminescence (PL) analyses confirmed the effective separation of photogenerated electron-hole pairs in CN/MgAl 0.80 Ce 0.20 -LDH, while electron spin resonance (ESR) results verified the derivation of superoxide radicals (·O 2 -) species amid CR photocatalytic degradation. [Display omitted] [ABSTRACT FROM AUTHOR]

Highlights: [•] Styrene–tin (IV) phosphate nanocomposite (ST/TPNC) ion exchanger was chemically prepared by simple sol–gel method at pH 0–1. [•] ST/TPNC exhibited higher ion exchange capacity as compared to its inorganic component. [•] ST/TPNC retained about 35.5% of the initial value of ion exchange capacity after heating up to 400°C. [•] ST/TPNC was used as efficient photocatalyst for the degradation of MB dye from aqueous system in the presence of solar light. [•] The pH titrations studies confirmed the monofunctional strong cationic nature of ST/TPNC. [ABSTRACT FROM AUTHOR]

Water pollution by organic pollutants has been a growing global problem in recent years, for which there is a great demand of efficient technologies for wastewater treatment. Remediation of water by photocatalytic oxidation has several advantages over adsorption or any other conventional techniques. This study reports a easy synthesis technique of a sulfur doped hollow TiO2 nanocatalyst for photo degradation of organic dye under solar light. The hollow doped TiO2 nano catalyst has significantly high specific surface area (318.11 m2 g-1) and low band gap (2.5 eV) compared to that of solid particles (130.94 m2 g-1 and 3.2 eV respectively), as a result it acts as an efficient photocatalyst under solar light. The methylene blue dye degradation ability of this catalyst is shown to be 98.6% compared to that of standard Degussa P25 (30%) as reported before. Additionally, the catalyst is also able to degrade 71% methylene blue dye during fifth times recycling without any further treatment because of its high surface area. So our sulfur doped hollow TiO2 nanoparticles can be used as a potential photocatalyst for environmental remediation applications. [ABSTRACT FROM AUTHOR]

Highlights: [•] The combination of AgBr–Ag3PO4 and MWCNTs efficiently reduced its photocorrosion. [•] Mechanisms of enhanced photocatalytic activity of AgBr–Ag3PO4/MWCNTs were revealed. [•] Possible degradation pathways of basic fuchsin and basic red 9 were proposed. [Copyright &y& Elsevier]

[Display omitted] • The CNTC hybrids exhibited excellent photocatalytic activity. • The Ti 3 C 2 loading improved the charge mobility and catalytic sites of g-C 3 N 4. • Enhanced activity mechanism and roles of active species were elucidated. The g-C 3 N 4 has received extensive attention for its unique properties. However, g-C 3 N 4 still suffers from the intrinsic limitations, which limit its large-scale applications. Hence, it is an urgent requirement to find a high-performance g-C 3 N 4 photocatalyst possesses both a high separation rate of charge carriers and a strong light response. In this work, we have designed a 3D/2D g-C 3 N 4 /Ti 3 C 2 (CNTC) heterojunction with a 3D interconnected porous structure as high efficiency photocatalyst for the photocatalytic hydrogen evolution (Pt as co-catalyst) and contaminant degradation. Benefiting from the 3D interconnected morphology and the incorporation of Ti 3 C 2 nanosheets, the CNTC hybrids exhibit a high specific surface area (85.08 m2 g−1) and highly efficient charge migration, thus leading to excellent catalytic performance for the hydrogen generation and organic dye elimination. In addition, the mechanism of improved photocatalytic performance was analysed by characterization measurements, active species analysis and density functional theory calculations. [ABSTRACT FROM AUTHOR]

This study presents core/shell Ag/SnO2 nanowires (Ag/SnO2NWs) as a new photocatalyst for the rapid degradation of organic compounds by the light from the visible range. AgNWs after coating with a SnO2 shell change optical properties and, due to red shift of the absorbance maxima of the longitudinal and transverse surface plasmon resonance (SPR), modes can be excited by the light from the visible light region. Rhodamine B and malachite green were respectively selected as a model organic dye and toxic one that are present in the environment to study the photodegradation process with a novel one-dimensional metal/semiconductor Ag/SnO2NWs photocatalyst. The degradation was investigated by studying time-dependent UV/Vis absorption of the dye solution, which showed a fast degradation process due to the presence of Ag/SnO2NWs photocatalyst. The rhodamine B and malachite green degraded after 90 and 40 min, respectively, under irradiation at the wavelength of 450 nm. The efficient photocatalytic process is attributed to two phenomenon surface plasmon resonance effects of AgNWs, which allowed light absorption from the visible range, and charge separations on the Ag core and SnO2 shell interface of the nanowires which prevents recombination of photogenerated electron-hole pairs. The presented properties of Ag/SnO2NWs can be used for designing efficient and fast photodegradation systems to remove organic pollutants under solar light without applying any external sources of irradiation. [ABSTRACT FROM AUTHOR]

A hybrid polyoxometalate-aminoazobenzene dye compound, (C 12 H 12 N 3 ) 3 PW 12 O 40 2CH 3 CN ( 1 ) has been synthesized in CH 3 CN/H 2 O solution under conventional reaction conditions. The structure of 1 was determined by single-crystal X-ray diffraction, and further characterized by IR spectroscopy, UV–vis spectra and diffuse reflectance spectra. The absorption edge of 1 is largely red-shifted compared to the pure polyoxoanions, due to the introduction of the dye cations. Photocatalytic studies indicated that compound 1 exhibits effective photocatalytic H 2 evolution activity under visible-light. [ABSTRACT FROM AUTHOR]

• MnS/Ag 2 WO 4 NCs was prepared by chemical co-precipitation method. • The NCs showed efficient visible light photocatalytic activity than individual particles. • MnS/Ag 2 WO 4 showed potent anti-microbial activity against gram positive and gram negative microorganisms. • Experimental results demonstrated that OH• and •O2- are the major reactive species involved in dye degradation. • MnS/Ag 2 WO 4 NCs showed MB dye degradation potency of 92.3%. In this study, the novel MnS/Ag 2 WO 4 photocatalyst was synthesized via chemical co-precipitation method and investigated its physical and structural characteristics using HR-TEM, N 2 adsorption and desorption studies, FT-IR, EDAX, PL, UV–vis DRS, ESR, XPS and XRD. The estimation of photocatalytic activity of synthesized photocatalysts was done using methylene blue (organic dye) in aqueous solution. The photocatalyst efficiency was superior for MnS/Ag 2 WO 4 with degradation of 92.3% when compared with bare MnS (67.23%) and Ag 2 WO 4 (58.93%). The kinetic study reveals that higher reaction kinetic rate achieved by the MnS/Ag 2 WO 4 compared with MnS and Ag 2 WO 4. The scavenging test reveals that •OH and O2-• took the important part in the degradation process. The six cycles test reveals that the photocatalyst is highly reusable by showing similar degradation efficiency throughout the six cycles. MnS/Ag 2 WO 4 was also possessed potential broad spectrum anti-microbial activity against B. subtilis and E. coli. Hence, MnS/Ag 2 WO 4 heterostructure can be used as an excellent photocatalyst as well as an effective anti-microbial agent. MnS/Ag 2 WO 4 would be a cost-effective, highly efficient photocatalyst and a good antimicrobial agent. [ABSTRACT FROM AUTHOR]