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A visible light driven 1D/2D-NiMoO4/BiOI nanocomposite photocatalyst was constructed by single step solvothermal method. Here, various composition of NiMoO4/BiOI nanocomposites were prepared by loading different amounts of NiMoO4 (1, 2, 3 wt %) to the BiOI. Among the as-prepared photocatalysts, 1 wt % of NiMoO4 on BiOI (NMBI-1) showed superior photocatalytic activity (92.7 %) under visible light irradiation. On analysis, the optimized NMBI-1 exhibited a lower bandgap energy value of 1.64 eV and also found to show around 2 and 3.7-times higher degradation ability for the removal of MB than the pure NiMoO4 and BiOI respectively. In addition, the optimized NMBI-1 nanocomposite photocatalyst exhibited excellent photostability and recyclability properties. The charge carriers on the interface of the NiMoO4 and BiOI enabled the easy transfer via the newly formed heterojunction, thereby increasing the photocatalytic performance. Additionally, the radical scavengers such as h+ and .OH were found to be the major species in the removal of MB under visible light illumination. Therefore, the 1D/2D-NiMoO4/BiOI nanocomposite photocatalyst materials could possibly be considered for the wastewater remediation processes.

In this research literature, a tungsten disulfide/iron cobaltite (WS

Amine-functionalized ZnO nanorods@graphene oxide (ZnO-NR/NH2/GO) nanocomposites prepared by a facile solution route have been investigated through X-ray diffraction, diffuse reflectance spectra, Raman spectra, scanning electron microscopy and transmission electron microscopy. The amine-functionalized ZnO-NR/NH2/GO-2 nanocomposite exhibits very strong visible light absorption. Dye-sensitized solar cell (DSSC) made of ZnO-NR/NH2/GO-2 nanocomposite (with optimum 2 wt % GO) photoanode delivers a power conversion efficiency (PCE) of 3.76% which is much higher than the efficiency of unmodified ZnO-NR/GO photoanodes based DSSC (2.27%). The enhancement of PCE is primarily caused by the increased current density, attributed to the incorporation of aminosilicate and GO on the surface of ZnO-NRs which facilitates rapid transfer of electron from conduction band of ZnO to conducting surface of FTO. This diminished recombination of photogenerated electrons and holes improve the electron transfer at the photoanode/electrolyte interfaces.

Supercapacitors are progressively being utilized for storage systems in sustainable nanotechnologies. A NiCoS nanostructure was synthesized on nickel foam by an in situ one-pot hydrothermal method at different reaction temperatures (80, 100, and 120 °C) keeping other reaction parameters such as pH and reaction time constant for supercapacitor applications. The SEM report revealed a plate-like nanostructures of NiCoS on nickel foam (NiCoS/NF). The electrode prepared at 100 °C exhibits better electrochemical activities compared to electrodes prepared at 80 and 120 °C. The integrated binder-free NiCoS/NF electrode for supercapacitor, optimized at 100 °C, manifested a large specific capacitance of 3309 mF cm−2 at a current density of 1 mA cm−2 with a notable rate capability of 427 mF cm−2 even at 10 mA cm−2. The asymmetric supercapacitor fabricated with optimized NiCoS/NF prepared at 100 °C exhibited an exceptionally high energy density of 2.04 mW h cm−3 at a power density of 42.64 mW cm−3.

A series of ternary ZnO hollow sphere/carbon quantum dots/reduced graphene oxide (ZnO/CQDs/r-GO) nanocomposites were successfully prepared via solvothermal technique in the presence of the polyethylene glycol 400 (PEG 400) as a solvent. The structural details of as-prepared ZnO/CQDs/r-GO nanocomposites were characterized by powder X-ray diffraction analysis. The morphological properties of the composite were analyzed using field emission scanning microscopy (FE-SEM). The visible light absorption ability of the as-prepared pristine and ternary nanocomposites was examined using UV–visible (UV–Vis) spectrophotometry. The photocatalytic activity of ZnO, ZnO/CQDs, ZnO/r-GO, and ZnO/CQDs/r-GO nanostructures were evaluated for the degradation of organic pollutants such as methylene orange (MO), rhodamine B (RhB), and methylene blue (MB). The different composites with various amounts of reduced graphene oxide (r-GO) and carbon quantum dots (CQDs) were synthesized to enhance photocatalytic activity. The ZnO/CQDs/r-GO composites showed excellent potential for photocurrent generation compared with ZnO, ZnO/CQDs and ZnO/r-GO under-stimulated sunlight. The effect of various parameters such as the effect of reaction temperature, catalyst concentration, pH, and concentration of MB dye has been also studied. The photo-assisted catalytic degradation properties of the catalyst after five cycles exhibit high stability.

ZSM-5:CeO2 nanocomposites were prepared by two-step hydrothermal method in combination with the wet impregnation method. The synthesized nanocomposites were characterized by XRD, FESEM, TEM, EDX, elemental mapping, FTIR and UV–vis analysis. The bandgap investigations were done using tauc plot and the bandgap of ZSM-5 has been reduced from 3.90 to 3.15 eV upon CeO2 loading. The synthesized nanocomposites were tested for photocatalytic activity under a halogen lamp and the effect of CeO2 loading on ZSM5 has been examined. Among the various nanocomposites synthesized, ZSM-5:CeO2 25 wt% exhibited better methyl orange degradation of about 95.6% with an initial dye concentration of 10 mg/l, pH 7, 100 mg of photocatalyst under halogen lamp for 75 min. Additionally, the effect of various reaction parameters like dye concentration (10–25 mg/l), photocatalyst dosage (25–125 mg), and pH (3–9) was probed to get better performance. Tapping experiments were conducted with various radical scavengers to get insight into the key active species responsible for the photodegradation of methyl orange. The result portrays the importance of hydroxyl radical for the degradation of methyl orange dye. Cycle test and stability studies showed that the photocatalyst was stable even after four cycles. In summary, ZSM-5:CeO2 nanocomposites can be a suitable photocatalyst for numerous applications in the field of photodegradation of organic contaminants.

Bismuth sulfide (Bi2S3) nanorods have been prepared using a simple and low-cost reflux method. This method is easy to handle and opens up a way to manufacture photocatalytic pigment at a low cost. The Bi2S3 catalyst was subjected to X-ray diffraction (XRD), UV–Visible spectroscopy (UV–Vis), scanning electron microscope, high-resolution transmission electron microscopy, FT-IR spectroscopy, thermogravimetric analysis (TG/DTA), and X-ray photoelectron spectroscopy. The structures of the Bi2S3 nanorod have been investigated and were seen to be orthorhombic. The electron microscopic observations showed that surfactants greatly affect the morphologies of the as-prepared Bi2S3 samples. The XRD and TEM results confirmed that the Bi2S3 nanorods have a high surface area and are good crystallinity. TEM measurements revealed that the average breadth and length is 75 nm and 385 nm for Bi2S3 nanorods prepared using NaOH. The uniform one-dimensional Bi2S3 nanorods are due to the presence of NaOH which controls the nucleation and growth process of Bi2S3 nanorods. The photocatalytic activity of the Bi2S3 nanocrystallites has been estimated by the degradation of methylene blue (MB) under the irradiation of halogen light. It was noted that the absorption peak corresponding to MB reduced indicating the photocatalytic nature of the sample. In these conditions, the maximum degradation of the dye was achieved within 140 min for KOH added Bi2S3 samples and the photodegradation efficiency is 87.98%. A possible photocatalytic reaction mechanism of the Bi2S3 samples has also been proposed.

Hexagonal phase zinc oxide (ZnO) nanostructures were synthesized via hydrothermal method and annealed at different temperatures viz., 200, 400, 600, 800 and 1000 °C. The prepared nanostructures were characterized by XRD, FTIR, FESEM, HR-TEM, UV-DRS and XPS techniques. The crystallite sizes of the prepared nanomaterails were calculated by Williamson–Hall plots method. The ZnO annealed at 200 °C showed a crystallite size of 18.7 nm while the ZnO annealed at °C showed a 46.2 nm. It is observed that when increasing the annealing temperature the crystallite sizes were increased due to induced growth of crystallites during annealing process. Moreover, the band gaps of the ZnO annealed at different temperatures showed a decreasing trend with increasing annealing temperatures. The photocatalytic performances were studied by analyzing the degradation of methylene blue in an aqueous solution. ZnO annealed at 1000 °C exhibited better photocatalytic activity (94%) due to enhanced crystallinity, comparatively lower bandgap and high oxygen vacancy.

MXene is a growing class of two-dimensional layered material that has been showed promising application in various energy storage and conversion technologies, due to its unique electrical, mechanical, surface and electrocatalytic properties. One of the promising applications of MXene is, its definite role as durable catalyst support material, for fuel cell anodic/cathodic reactions. Very recently, MXene supported catalysts have been identified as potential and stable support for various Pt and non-Pt metals designed for cathodic oxygen reduction reaction and it has been proved as excellent material to enhance the oxygen reduction kinetics. This had motivated the researchers to explore MXene as catalyst support for anodic methanol/ethanol oxidation reactions. In this review, recent developments in experimental and theoretical research on MXene-based electrocatalysts for the methanol/ethanol oxidation reactions are examined and overviewed. After careful examination of the available literature, we presume that MXene supported electrocatalyst showed enhanced methanol/ethanol oxidation kinetics and therefore believed to have tremendous opportunities as durable catalyst support for alcohol fuel cells. However, researchers also consider several limitations and challenges that must be addressed for efficient application of MXenes as catalyst supports. Therefore, current research on MXenes with respect to the methanol/ethanol oxidation are discussed, with a focus on synthesis strategies, oxidation kinetics, and factors responsible for enhancing the electrocatalytic performance. Several strategies for the further development of efficient and durable MXene supported catalysts are also proposed.

Photocatalysis is one of the fascinating fields for the wastewater treatment. In this regard, the present study deals with an effective visible light active BiYO3/g-C3N4 heterojunction nanocomposite photocatalyst with various ratio of BiYO3 and g-C3N4 (1:3, 1:1 and 3:1), synthesised by wet chemical approach. The as-synthesised nanocomposite photocatalysts were investigated via different physicochemical approaches like Fourier transform infrared (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), transmission electrons microscopy (TEM), UV-vis diffuse reflectance spectroscopy (DRS), photoluminescence (PL) and photoelectrochemical studies to characterise the crystal structure, morphology, optical absorption characteristics and photoelectrochemical properties. The photocatalytic degradation ability of the prepared photocatalytic samples were also analysed through the degradation of RhB in the presence of visible light irradiation. Of all the synthesised photocatalysts, the optimised CB-1 composite showed a significant photocatalytic efficiency (88.7%), with excellent stability and recyclability after three cycles. O2.− and •OH radicals were found to act a major role in the RhB degradation using optimised CB-1 composite and it possessed ~ 1 times greater photocurrent intensity than the pristine g-C3N4 and BiYO3. In the present work, a direct Z-scheme heterojunction BiYO3/g-C3N4 with a considerably improved photocatalytic performance is reported.

A novel FeMoO4/g-C3N4-2D/2D Z-scheme heterojunction photocatalyst was prepared via wet chemical method. The observed structural morphology of FeMoO4/g-C3N4 reveals the 2D-iron molybdate (FeMoO4) nanoplates compiled with the 2D-graphitic carbon nitride (g-C3N4) nanosheets like structure. The photocatalytic activity of the g-C3N4, FeMoO4, and FeMoO4/g-C3N4 composites were studied via the degradation of Rhodamine B (RhB) as targeted textile dye under visible light irradiation (VLI). The optimal FeMoO4/g-C3N4 (1:3 ratio of g-C3N4 and FeMoO4) composite show an enhanced degradation performance with rate constant value of 0.02226 min-1 and good stability even after three cycles. Thus, the h+ and O2•－are the key radicals in the degradation of RhB under VLI. It is proposed that the FeMoO4/g-C3N4 Z-scheme heterojunction effectively enhances the transfer and separation ability of e-/h + pairs, by the way increasing the photocatalytic efficiency towards the RhB degradation. Thus, the newly constructed Z-scheme FeMoO4/g-C3N4 heterojunction photocatalyst is a promising material for the remediation of wastewater relevant to elimination of toxic effect in marine environment.

Excess sludge produced from biological wastewater treatment plant in petroleum industry is a kind of hazardous solid waste. Converting the sludge into biochar catalysts may help to reduce its environmental risk, recover resources and increase economic efficiency. However, the role of the sludge biochar in persulfate activation remains unclear, limiting its application in removing organic pollutants from water body. In this study, metal-rich petrochemical sludge was used to produce activated sludge biochar (ASC) via a two-step method of pyrolytic carbonization (400 °C-800 °C) and subsequent KOH activation (abbreviated as ASC 400-800). The physio-chemical properties of ASC 400-800 were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET) and Raman. The chloramphenicol (CAP) removal performances of ASC 400-800/peroxymonosulfate (PMS) systems were evaluated. Results showed that porous sludge biochar was successfully prepared by the two-step method. At 800 °C, the specific surface area of ASC reached the highest value of 202.92 m

The development of efficient, scalable, and economically viable electrode materials with high specific capacitance is of great significance for supercapacitor applications. Herein, α-Fe2O3 nanoparticles, α-Fe2O3/rGO, and α-Fe2O3/SnO2/rGO nanocomposite were synthesized by a one-step hydrothermal method. Different characterization techniques were used to study the physical and chemical properties of the prepared materials. The powder XRD measurement revealed that the formation of the ternary composite without any impurities. As characterized by SEM and TEM techniques, both α-Fe2O3 and SnO2 nanoparticles were embedded on two-dimensional reduced graphene oxide sheets. The electrochemical properties of the prepared electrode materials were studied by cyclic voltammetry and galvanostatic charge/discharge, and impedance spectroscopy techniques in a 6 M KOH electrolyte solution. All the electrode materials exhibit Faradic reaction peaks in CV curves which imply the pseudocapacitive nature of the prepared materials. The ternary α-Fe2O3/SnO2/rGO nanocomposite demonstrated the enhanced specific capacitance of 821 Fg−1 at 1Ag−1 than that of α-Fe2O3 nanoparticles (373 Fg−1 at 1Ag−1), and α-Fe2O3/rGO (517 Fg−1 at 1Ag−1) nanocomposite with excellent cyclic retention (98.7%) after successive 10,000 cycles. This improved electrochemical performance of ternary α-Fe2O3/SnO2/rGOnanocomposite is mainly attributed to the surface properties of nanostructures of metal oxides and an excellent conductive network. Moreover, the asymmetric supercapacitor (ASC) device was fabricated using the ternary α-Fe2O3/SnO2/rGOnanocomposite as the anode material and rGO as the cathode material. The ASC device showed an energy density of 17 Wh Kg−1 at a power density of 3585 W kg−1 and retains 94.52% capacitance after successive 5000 cycles at a current density of 10Ag−1.

Nitrobenzene (NB) is toxic even at low concentrations and hence, its contamination in the environment is a pervasive concern. The electrochemical techniques have emerged as rosy method to sense and degrade NB and graphitic carbon nitride (g-C3N4) catalysts are found to be promising for this. In this study, silver nanoparticles (AgNPs) decorated N-[3-(trimethoxysilyl)propyl]ethylenediamine (EDAS) modified graphitic carbon nitride nanocomposites (EDAS/(g-C3N4-Ag)NC) having various silver concentrations are prepared through a facile method and applied for the electrochemical sensing of NB derivatives. UV-vis absorption edge at 430 nm together with a broad surface plasmon resonance (SPR) peak at 450 nm indicates the existence of AgNPs on the g-C3N4 nanosheets. FT-IR spectra endorse the presence of g-C3N4 nanosheets in the composite. The presence of Ag in EDAS/(g-C3N4-Ag)NC is confirmed by transmission electron microscopy, energy dispersive X-ray analysis and cyclic voltammetry (CV). The nanocomposite prepared with 2 mM Ag+ shows superb electrocatalytic activity towards the reduction of nitrobenzene and its derivatives. Sensitivity of the modified electrode and limit of detection (LOD) for NB assessed by square wave voltammetry are found to be 0.594 A M− 1 cm− 2 and 2 µM, respectively, in the linear range of 5–50 µM.

ZnO hexagonal tube and ZnO/r-GO nanocomposites were synthesized by hydrothermal method and the nanostructures were characterized by XRD, UV-DRS, PL, FTIR, FESEM, and TEM techniques. The main violet emission peak of the synthesized nanostructures is due to the transition between interstitial zinc and hole (valence band) of ZnO. The potential of ZnO/r-GO nanocomposite was evaluated using methyl orange (MO) and rhodamine-B (RhB), and the results were compared with the activity of synthesized ZnO nanostructures. More than 95% of MO and RhB were by ZnO/r-GO nanocomposite and it was found to be higher than that of ZnO hexagonal tube. The degradation MO and RhB were found to follow first-order kinetics and it has a rate constant of 7.68 × 10−2and 7.83 × 10−2 min−1, respectively. These results are mainly due to the enhanced charge transport property. Trapping experiments show that superoxide radical anion and hydroxide radicals are chief species responsible for the degradation of MO and RhB. The chemical stability of the nanocomposite was evaluated by cycle test experiments and it reveals that the catalyst can be reused up to few cycles without considerable loss of photocatalytic activity. This work affords a simple stratagem to integrate ZnO hexagonal tubes and r-GO nanosheets to construct effective catalysts for the degradation of organic compounds.

A visible light driven BiOBr/Bi

Correction for ‘green synthesis of silver nanoparticles using plant extracts and their antimicrobial activities: a review of recent literature’ by Chhangte Vanlalveni et al., RSC Adv., 2021, 11, 2804–2837, https://doi.org/10.1039/D0RA09941D.

A new probe 4-bromo-2-((E)-((Z)-((5-bromo-1H-indol-2-yl) methylene) hydrazono) methyl) phenol (BHPL) has been developed and successfully employed for the detection of Al3+/Zn2+/F-ions in DMSO: H2O (9:1) system. The photophysical evaluation of BHPL with cations/anions were rationalized by UV-visible and fluorescence spectroscopy. The stoichiometric binding mode of BHPL with Al3+/Zn2+/F- ions were confirmed by Job’s plot analysis and strongly supported by1H NMR titration,19F NMR analysis and electrospray ionization mass spectroscopy (ESI-MS) techniques. The optimized geometries of BHPL with their complexes and ground state energy levels were gauged via DFT calculations. In the biological environment, BHPL could perform as an obvious fluorescent chemical tool to detect Zn2+ionsin HeLa cells and fluorescence imaging analysis in Zebrafish embryos.

Novel hollow sphere morphologied zinc sulphide@carbonaceous aerogel (ZnS@CA) composites with different ZnS content were fabricated using a simple hydrothermal carbonization treatment following by a facile in situ growth method. The fabricated composites were used as catalysts for chemical degradation of the methylene blue (MB) and for hydrogen evolution. Our photocatalytic studies are found, from the photocatalytic results obtained by different ZnS@CA materials, that 55 wt%ZnS@CA exhibits the excellent photocatalytic performances for MB degradation and the highest rate of hydrogen production that are correspondingly 1.7- and 8.1-fold higher than that of pure ZnS. This improved photocatalytic performance could be mainly attributed by unique 3D catenulate carbon networks, which can be highly favorable to disperse of ZnS on the surface of CA. An synergetic properties between CA and ZnS could be highly beneficial to the photo-generated electron–hole separation. The hollow microsphere structured ZnS nanoparticles allow multi-reflections of light within the interior cavity and increases the capture efficiency of visible light. A possible photocatalytic mechanism of the main active radicals has also been proposed. This work opens up the new prospects for a low-cost biomass-based sulfide photocatalysts used for the environmental purification and hydrogen generation.

Identification of electrode materials with excellent specific capacity and energy density are significant factors for the development of high-performance supercapattery device. Transition metal tungstate is an emerging electroactive material for supercapattery due to its excellent electrical conductivity and electrochemical properties. Herein, the mesoporous Ni(1−x)Co(x)WO4 nanomaterials were synthesized by a one-step hydrothermal method as an anode material for supercapattery. The apparent discrepancy in mesoporous structures was incited by varying the stoichiometric ratio of Ni/Co in the Ni(1−x)Co(x)WO4 system which lead to an increase in the electrochemical properties. Among the synthesized electrode materials, Ni0.5Co0.5WO4 electrode material delivers the high specific capacity of 634.55 Cg−1 at 1 Ag−1 with an excellent rate capability of 92% after 10,000 cycles at 10 Ag−1. The solid-state supercapattery constructed with Nio.5Co0.5WO4 and reduced graphene oxide as positive and negative electrodes, respectively. The device exhibits the maximum specific capacity of 134.70 Cg−1 at 0.5 Ag−1 and energy density of 56.12 Wh kg−1 at 500 W kg−1 with long-term cyclic stability (90% capacity retentively after 20,000 cycles). The high performance of this electrode material has been attributed to the synergetic effect between bimetallic (Ni and Co) redox centers, a mesoporous structure that provides a larger redox cites, rich electrical conductivity, shorter diffusion length, and faster electrochemical kinetic rates for electrochemical reactions.

The design of switchable hybrid systems to control the catalytic activity using stimuli-responsive polymers have a great significance in the precise manipulation of the oxidation reactions. Herein, we proposed a novel and facile approach for the synthesis of a dual-responsive silica nanohybrid catalyst by combining the temperature-responsive poly N-isopropylacrylamide (PNIPAM) and pH-responsive poly 4-vinylpyridine (P(4-VP)) with MCM-41 as integrated support via free radical polymerization. The prepared switchable material was decorated with silver nanoparticles (AgNPs) through the co-reduction approach. The X-ray photoelectron spectroscopy (XPS) data confirmed the existence of AgNPs in the zero oxidation state while the dynamic light scattering (DLS) measurements revealed that the material exists in maximum swelling confirmation at low temperature (

Correction for ‘A review of the recent progress on heterogeneous catalysts for Knoevenagel condensation’ by Jimmy Nelson Appaturi et al., Dalton Trans., 2021, 50, 4445–4469, DOI: 10.1039/d1dt00456e.

Aluminium-containing spherical mesoporous silica nanoparticle (AlSMSN) materials were synthesized for the first time using cetyltrimethylammonium bromide (CTMABr) as a structure-directing agent under nonhydrothermal conditions at room temperature. The effect of the nature of the Al source on the synthesis of the AlSMSN materials was investigated using a variety of Al sources. The effect of higher Al ion incorporation on the structural and textural properties of the AlSMSN materials was evaluated by varying the nSi/nAl ratios, and an efficient chemical treatment method was developed for the removal of superficial octahedral Al ions from the surface of the AlSMSN materials. The synthesized AlSMSN materials were characterized using ICP-AES, XRD, N2 adsorption, 27Al & 29Si MAS NMR, FTIR, TEM, and FE-SEM techniques. ICP-AES results revealed incorporation of a high Al ion content (nSi/nAl = 24) into the spherical mesoporous silica nanoparticle materials. For all of the calcined AlSMSN materials, the XRD reflection peaks shifted to lower angle with increasing Al ion content, resulting in an increase of the unit cell parameter. The textural parameters of the AlSMSN materials, except for the surface area, found from nitrogen adsorption measurements, increase with an increase in the amount of aluminium isopropoxide in the synthesis gel. The location and coordination of Al ions on the walls of the AlSMSN materials and the amount of Al ions incorporation were determined from the 27Al MAS NMR measurements. TEM and FE-SEM images demonstrated that the AlSMSN materials comprise spherical particles with hexagonally packed uniform mesoporous channels. Furthermore, the AlSMSN(20) with a higher Al content exhibits better hydrothermal stability than the AlSMSN(100) congener with a lower Al content. Catalyst recyclability studies showed that the washed catalyst (W-AlSMSN(20)) exhibited exceptional catalytic activity during t-butylation of phenol with 95.4% 4-t-butylphenol (4-TBP) selectivity due to removal of superficial octahedrally coordinated Al ions on the surface of active sites.

The incessant formation of chain-like IBN-4 mesoporous silica (ICMS-N) with long channels running along the length of hexagonal rods have been directly achieved by the co-condensation of 3-aminopropyltriethoxysilane (APTES) and tetraethylorthosilicate as the silica source in the presence of Pluronic P123 and fluorocarbon (FC-4) surfactants as structure directing agents. The newly synthesized materials were successfully characterized using SAXS, N2-physisorption, FT-IR, XPS, 29Si NMR, TEM, SEM and elemental analysis. TEM images confirmed the chain-like morphologies, whereas SEM studies showed that the synthesized ICMS-N particles possess length >10 μm. Moreover, the as-formed material was tested for the removal of oxyanions such as arsenate and chromate, and it exhibited the maximum adsorption capacity of 55 and 35 mg g−1 for ICMS-N15, respectively. The formation of quaternary species of amine on the surface of the ICMS-N enhanced the adsorption capacity towards arsenate and chromate under acidic pH and the adsorption isotherm fits with Langmuir monolayer adsorption. Naturally, existing anions such as nitrate, sulfate, phosphate and chlorides with 1 × 10−2 M have no significant effect on the adsorption of heavy metal ions; moreover, reusability tests were also carried out.

Ionic liquids immobilized onto structurally modified polyethylene glycol (PEG) were prepared through the reaction of 1-(2-hydroxyl-ethyl)-3-alkyl-imidazolum chloride and PEG-succinic acid. Elemental analysis, SEM, 13 C NMR and FT-IR showed that the immobilized ionic liquid groups were well incorporated onto the PEG support. The PEG-supported ionic liquids (PEG-IL) proved to be an effective heterogeneous catalyst for the solventless synthesis of cyclic carbonate from allyl glycidyl ether (AGE) and carbon dioxide. PEG of lower molecular weight had higher conversion of AGE. High temperature and carbon dioxide pressure and the presence of zinc halide co-catalyst were favorable for AGE conversion. PEG-IL can be reused for the reaction through up to three consecutive runs without significant loss of its catalytic activity.

In this study, various ionic liquids immobilized onto montmorillonite clay (IL-MMT) were prepared by ion-exchange reaction between the ionic liquids and ions in the clay interlayer. Tetra-alkyl ammonium chlorides were used as the ionic liquid precursors. The IL-MMTs were characterized by elemental analyses (EA), BET, XRD, 13 C NMR, FT-IR, and SEM. The surface areas and d -spacings of the IL-MMTs increased with increasing alkyl chain lengths. The IL-MMTs showed good catalytic activity for the synthesis of the cyclic carbonate from alkyl glycidyl ether (AGE) and carbon dioxide. The effects of the IL cation structure, and reaction parameters such as temperature and CO 2 pressure on the reactivity of IL-MMTs were also discussed. The catalyst could be reused in up to four consecutive runs without a significant reduction in the initial activity.

To achieve a high level of heavy metal adsorption, 1,1′,1″-(1,3,5-triazine-2,4,6-triyl)tris(3-(3-(triethoxysilyl)propyl)urea) (TTPU) was synthesized as a novel melamine precursor and incorporated on the silica surface of periodic mesoporous organosilica (PMO). The melamine modified PMOs (MPMOs) were synthesized under acidic conditions using TTPU, tetraethylorthosilicate (TEOS) and Pluronic P123 as a template and the modified PMOs were characterized using the relevant instrumental techniques. The characteristic materials were used as adsorbents for the adsorption of Fe(III) ions. Fe(III) adsorption studies revealed MPMO-7.5 to be a good absorbent with higher adsorption efficiency than other MPMOs.

Polyimide(PI)/graphene oxide(GO) nanocomposite films were prepared by chemical cross-linking using small amounts of divalent Mg ions. The PI/GO nanocomposites showed enhanced tensile properties compared to pristine PI due to the presence of exfoliated GO in the PI matrix as well as crosslinking between poly(amic acid) (PAA), which is a precursor of PI, and GO by Mg ions. The hydrogen bonds between PAA and GO suppressed the phase separation between PI and GO, and small amounts of Mg ions can bond between the oxygen functional groups and carboxylate groups of GO and PAA.

Well hexagonally ordered CrSBA-15 catalysts synthesized by different hydrothermal methods were used, for the first time, for the selective synthesis of benzophenone (BP O) by liquid-phase oxidation of diphenylmethane (DPM) under various reaction conditions. To investigate the leaching of chromium species on the surface of silica networks, the results of original and reusable Cr-containing mesoporous silica catalysts were correlated and compared, and the catalytic activity of washed CrSBA-15(8) was also demonstrated. Based on the all catalytic results for this reaction, CrSBA-15(8) was found to be a highly active and an environmentally friendly solid catalyst and has superior catalytic activity than other Cr-containing mesoporous catalysts.

Mesoporous CrSBA-15 catalysts synthesized with a variety of n Si / n Cr ratios by pH-aDH method were used in the production of enones by the liquid-phase oxidation of benzylic compounds. To investigate the leaching of chromium species on the silica surface, CrSBA-15(8) was chemically treated with ammonium acetate solution while the Cr-containing mesoporous silica catalysts used for these reactions were regenerated by washing and calcinations. The treated catalysts such as washed CrSBA-15 and regenerated CrSBA-15 catalyst were used/reused in these reactions to find their catalytic activities. Furthermore, the influences of various reaction parameters such as temperature, time, ratios of reactant and solvents on the synthesis of tetraline (T O) have been systematically investigated. Based on the catalytic investigations, CrSBA-15(8) catalyst is found to be a highly active, recyclable and promising heterogeneous catalyst for the selective synthesis of enones, and it has superior catalytic activity in the oxidation of benzylic compounds than CrMCM-41.