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Surface catalyzed reactions can be a convenient way to deactivate toxic chemical warfare agents (CWAs) and remove them from the contaminated environment. In this study, pure titanium oxide, magnesium hydroxide, and their composites TiO2/Mg(OH2) were prepared by thermal decomposition and precipitation of the titanium peroxo-complex and/or magnesium nitrate in an aqueous solution. The as-prepared composites were examined by XRD, XPS, HRTEM, and nitrogen physisorption. Their decontamination ability was tested on CWA surrogates and determined by high-performance liquid chromatography (HPLC) and gas chromatography coupled with mass spectrometry (GC-MS). Dimethyl methyl phosphonate (DMMP) was used as a G simulant for the nerve agents sarin (GB) and soman (GD) while 2-chloroethyl ethyl sulfide (2-CEES) and 2-chloroethyl phenyl sulfide (2-CEPS) were used as surrogates of sulfur mustard (HD). The activity of the as-prepared composites was correlated with acid–base properties determined by potentiometric titrations and pyridine adsorption studied by in situ DRIFTS. The mixing of Ti and Mg led to an increase of the surface area and the amount of surface –OH groups (with an increasing amount of Ti) that caused improved degradation of DMMP.

A series of titania-tin oxide binary nanosized mesoporous materials with various composition were successfully obtained by template assisted hydrothermal technique. They were characterized by nitrogen physisorption, XRD, TEM, XPS, UV-Vis, FTIR of adsorbed pyridine and Raman spectroscopes. The reduction properties of the composites were studied by TPR with hydrogen. Two environmental feasible processes, such as total oxidation of ethyl acetate as representative VOCs and decomposition of methanol as hydrogen source, which are also sensitive both to the surface and redox properties of the solids, were used as catalytic tests. On the base of detailed analyses of the data from the complex physicochemical study and comparison with the reference samples, obtained by homogeneous precipitation with urea, a possible mechanism of the formation of TiO2-SnO2 binary materials was proposed and discussed in a view of catalyst design control.

Solar light-induced photodecomposition of organophosphorus warfare agent simulant dimethyl methylphosphonate (DMMP) on the surfaces of TiO2/graphene oxide (GO) nanocomposites was studied by in situ DRIFT spectroscopy. Nanocomposites containing 1 and 2 wt% GO, respectively, were prepared by two different aqueous methods. All nanocomposites were shown to effectively adsorb and partly dissociate DMMP as shown by the formation of surface coordinated methoxy groups. Solar light illumination induced rapid decomposition of the adsorbed species to yield various ionic and surface coordinated formate and carbonate species as the main intermediate products. Both the kinetics of adsorbed species decomposition and the formation of various intermediates were strongly affected by the presence of GO, as compared to pure TiO2 nanoparticles. The two synthesis routes yielded nanocomposites with different degrees of reduction of GO that correlated with their reactivity towards DMMP adsorption and photodegradation. Upon illumination, rapid depletion of water was observed on the TiO2/GO nanocomposites and was attributed to a water splitting reaction, which competed with the DMMP photo-oxidation reaction.

Surface catalyzed reactions can be a convenient way to deactivate toxic chemical warfare agents (CWAs) and remove them from the contaminated environment. In this study, pure titanium oxide, magnesium hydroxide, and their composites TiO

ZnO*ZnO2 mixture was prepared by thermal hydrolysis of a zinc peroxo-complex precursor in presence of Sn2+ and Sn4+ ions. The effect of different tin valence states on structure and photocatalytic properties of the resulting products was investigated. All samples before annealing contained ZnO2 and except one sample also SnO2. Microstructural analysis showed a difference in morphology between the two sets of samples. A difference was also observed for the specific surface area. The photocatalytic decolorization of Orange II dye was employed to determine the photocatalytic activity of the samples; Sn2+ doped samples were more active than Sn4+ doped ZnO samples. Temperature 600 °C was optimal for annealing - the sample ZnP150Sn2 annealed at 600 °C had the highest rate constant (0.0730 min−1) among the samples. Additional increase of Sn2+ amount led to further increase in rate constant (0.0937 min−1 for the sample ZnP200Sn2) up to a certain point.

Two water-based methods were used to produce TiO2/graphene oxide (GO) nanocomposites with 1 and 2 wt.% GO. Both procedures exclude the use of organometallic precursors, as well as the high-pressure and high-temperature treatments, which facilitate pure and energy efficient synthesis amenable for larger scale synthesis. Nanocomposites with narrow (

Template assisted hydrothermal and homogeneous precipitation with urea techniques were used for the preparation of TiO2-ZrO2 binary oxides with wide range variation of their composition. Low temperature nitrogen physisorption, XRD, SEM, HRTEM, XPS, UV–vis, FTIR, FTIR of adsorbed pyridine and Raman spectroscopy were used for the characterization of the obtained samples. Their catalytic properties were tested in total oxidation of ethyl acetate as a representative VOCs and methanol decomposition as hydrogen carrier. It was established that the template assisted hydrothermal technique provoked preparation of materials with good crystallinity, high BET surface area and well developed mesoporous structure, while the homogeneous precipitation with urea method facilitated the formation of more highly dispersed in wide Zr/Ti region samples. The degree of incorporation of Zr4+ ions into titania lattice could be controlled by the samples composition and the preparation method used, which revealed good opportunity for effective and simple regulation of their catalytic properties.

The ability of pilot samples of destructive metal oxide sorbents to decompose a sulfur mustard-type chemical warfare agent into nontoxic products in a nonaqueous solvent was compared with that of the commercial product FAST-ACT. Additionally, samples of the destructive metal oxide sorbents were used to decompose nitrogen mustards, which are used as chemotherapeutic agents, in water, and the results were compared with those of FAST-ACT. All the prepared pilot samples exhibited stoichiometric activities, i.e., the degradation rate expressed by the rate constant, k [s–1, min–1], and the decomposition efficiencies, which are expressed by the degree of conversion d [%], higher than those of the comparative commercial product FAST-ACT. Scaling up the sulfur mustard decomposition from the laboratory conditions (reaction volume, 4 L) to quarter-operating (pilot) reaction conditions (reaction volume, 100 L) had a positive effect on the reaction and final product.

The undemanding water-based synthesis was employed for the preparation of TiO 2 /CeO 2 composites supported on Montmorillonite (MT). The prior plasma treatment of Montmorillonite led to significantly faster dispergation in water during the synthesis. The composites were used as reactive adsorbents against toxic organophosphorus pesticide parathion methyl. Efficient pillaring of the Montmorillonite layers by surface deposition of TiO 2 /CeO 2 composites reflected in a substantially improved degradation activity towards parathion methyl in non-polar (heptane) and polar solvents (acetonitrile) investigated by HPLC/DAD. Moreover, the use of plasma treated Montmorillonite in the composites resulted in a higher degradation rate than with use of pristine MT. The formation of composites and their physicochemical properties were studied by XRD, XPS, FTIR, nitrogen physisorption, SEM and HRTEM/EDS mapping. Prior plasma treatment of the MT in a simple arrangement led to an easier formation of the composites and caused further improvement of the samples activity.

Graphene oxide/MnO 2 nanocomposite was prepared by thermal hydrolysis of potassium permanganate (KMnO 4 ) and 2-chloroacetamide aqueous solutions with graphene oxide (GO) suspension. The synthesized samples were characterized by specific surface area (BET) and porosity determination (BJH), X-ray Diffraction (XRD) and high-resolution electron microscopes (HRSEM, HRTEM). These nanocomposites were used in an experimental evaluation of their adsorption activity with nerve agent simulants dimethyl methyl phosphonate (DMMP) and triethyl phosphate (TEP) in aqueous media. The nanocomposites exhibited enhanced adsorptive degradation ability compared to pure manganese oxide (MnO 2 ) and GO. The GO amount in the nanocomposites affected their degradation activity substantially. The best adsorption efficiency was observed for samples with moderate GO amount. Three methods were used to observe the mechanism of the nerve-agent simulants deactivation: Gas chromatography with mass spectrometry (GC–MS), High-Performance Liquid Chromatography (HPLC) and in situ Infrared spectroscopy (FTIR). It was shown that the hydrolysis on the surface of prepared nanocomposites yields volatile primary alcohols (methanol and ethanol) as the main hydrolysis products.

High surface area mesoporous ceria-titania binary materials with high Lewis acidity and improved reduction properties were synthesized using template assisted hydrothermal technique. The obtained materials were characterized by low temperature nitrogen physisorption, XRD, SEM, TEM, Raman, UV–vis, XPS, FTIR, FTIR of adsorbed pyridine and thermo-programmed reduction with hydrogen. Their catalytic activity was tested in total oxidation of ethyl acetate and methanol decomposition to CO and hydrogen with a potential application in VOCs elimination and alternative fuels, respectively. The structural changes in the binary materials, which could be tuned by the variation in the Ce/Ti ratio and the temperature of hydrothermal treatment, provoked significant changes in their textural, surface and redox properties, which is in close relation to the catalytic activity and selectivity in various catalytic processes. The intimate contact between the individual oxides results in the formation of different catalytic active sites and their role in the studied catalytic reactions was discussed in details.

Amino-functionalized graphene oxide was reacted with isocyanate monomer to evaluate the potential application of GO-NH2 as a functional filler for the preparation of polyurethane nanocomposites. A set of advanced techniques (XRD, FTIR spectroscopy, Raman spectroscopy, and TEM) was used to characterize the functionalized samples, together with elemental analysis and XPS, which provided valuable information on the total N content and the nitrogen (chemical) speciation, respectively. In addition, a simple and fast spectrophotometric method was developed for the estimation of accessible amino groups (functional speciation). The method is based on the interaction of NH2 groups with the anionic dye acid orange 7 under appropriate conditions (pH = 3.6) and shows good precision. It can be advantageously used for the fast evaluation of the GO-NH2 reactivity with isocyanate monomer and its applicability as the polymer filler.

The widespread use of cytotoxic drugs in the treatment of cancer has led to the production of large amounts of contaminated wastes with high exposure risk of medical staff handling cytostatics. For this reason it is essential to use a highly effective and fast decontaminating agent for the decontamination process. Currently used decontamination agents based on NaOCl and NaOH are not sufficient according to our results and also according to literature data. Therefore we have developed a new decontamination agent based on titania nanoparticles, which appears to be a very efficient and fast decontamination agent according to our research data. Anthracycline antibiotics are valuable and frequently used drugs in various chemotherapeutic schemes. They have high efficacy, but also high toxicity, e.g. myelosuppression and cardiotoxicity. They can also act as vesicants in the case of extravasation. Due to their mechanism of action, anthracycline antibiotics have mutagenic and carcinogenic effects. Long term contact, even with a trace amount, can cause changes in human health. Safe decontamination of cytotoxic drug contaminated areas with an agent, which can cause degradation to non-toxic products, is essential. High sorption ability of doxorubicin and epirubicin to titania predisposes TiO2 to become a new, effective and inexpensive agent for area decontamination and degradation of anthracycline antibiotics.

The unusual ability of cerium oxide to cleave phosphoester bonds under relatively mild (ambient) conditions was demonstrated using thiamine pyrophosphate (TPP) and nicotinamide adenine dinucleotide (NAD) as model compounds. This phosphatase-mimetic ability can be exploited in biology or medicine, e.g., for protein design; however, it represents a potential threat to vital systems in living organisms, such as the phosphate backbone of DNA and RNA. The ability of cerium oxide to promote the cleavage of the bridging pyrophosphate group in the NAD molecule was examined for the first time; it was shown that the cleavage products differ markedly from the commonly observed products of enzymatic or non-enzymatic hydrolysis of NAD. This ability is highly specific for cerium oxide; it was not observed to a comparable extent with any of the other tested metal oxides (La2O3, Nd2O3, Pr6O11, TiO2, manganese oxide and several iron oxides). The phosphatase-mimetic ability stems from the unique properties of cerium cations and may be related to measurable and, to some extent, adjustable characteristics, such as crystallinity, surface area, Ce3+/Ce4+ ratio or the content of surface functional groups. The in-house prepared nanocrystalline cerium oxide exhibited a markedly higher phosphatase-mimetic ability than the commercial nanoceria. The interactions of the cerium oxide nanoparticles with TPP and NAD were also examined with the aid of molecular dynamics simulations.

Anthracyclines are a class of pharmaceuticals used in cancer treatment have the potential to negatively impact the environment. To study the possibilities of anthracyclines (represented by pirarubicin and valrubicin) removal, chemical inactivation using NaOH (0.01 M) and NaClO (5%) as decontamination agents and adsorption to powdered nanocrystalline titanium dioxide (TiO2) were compared. The titanium dioxide (TiO2) nanoparticles were prepared via homogeneous precipitation of an aqueous solution of titanium (IV) oxy-sulfate (TiOSO4) at different amount (5-120 g) with urea. The as-prepared TiO2 samples were characterized by XRD, HRSEM and nitrogen physisorption. The adsorption process of anthracycline cytostatics was determined followed by high-performance liquid chromatography coupled with mass spectrometry (LC-MS) and an in-situ Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) technique. It was found that NaClO decomposes anthracyclines to form various transformation products (TPs). No TPs were identified after the reaction of valrubicin with a NaOH solution as well as in the presence of TiO2 nanoparticles. The best degree of removal, 100% of pirarubicin and 85% of valrubicin, has been achieved in a sample with 120 grams of TiOSO4 (TIT120) and TiO2 with 60 grams (TIT60), respectively.

Iron-titanium binary oxides were synthesized by template-assisted hydrothermal method. The effect of the variation in the Fe/Ti ratio and the temperature of hydrothermal treatment on the phase composition, structural, textural and redox characteristics of thus obtained materials was studied by Nitrogen physisorption, XRD, SEM, HRTEM, XPS, Raman, UV–vis, FTIR and Moessbauer spectroscopy and TPR with hydrogen. The contribution of various features of the samples on their catalytic behaviour in total oxidation of ethyl acetate as a representative VOC was in the focus of the discussion. The binary materials represent a complex mixture of pure and substituted anatase and/or hematite phases with different dispersion and proportion, which can be controlled by both the variation in the Fe/Ti ratio and the temperature of hydrothermal treatment. The stabilization of finely dispersed hematite-like particles in the vicinity of Fe 3+ substituted in titania was considered as an important factor for the improvement of the catalytic activity and selectivity in total oxidation of ethyl acetate and it is favoured by the lower Fe/Ti ratio and the lower temperature of the hydrothermal treatment.

The uniform Sn-doped CuO nanoparticles were synthesized by a simple solution method at a low temperature. The prepared samples were investigated by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), electron microscopy techniques (HRSEM, HRTEM, SAED, STEM and EDS elemental mapping), atomic force microscopy (AFM), UV/Vis spectroscopy, nitrogen physisorption (BET) and by evaluation of the catalytic activity on the degradation of Rhodamine B. The tin doping had a considerable influence on the morphology of CuO. The gradual narrowing of the particles morphology in the crystallographic [010] direction was observed with increasing the dopant concentration. The plate-like, rectangularsquare and rod-like CuO nanoparticles were obtained. The mechanism of a crystal growth of CuO associated with doping is proposed. The tin doping also affected the structural and optical properties of CuO. Increasing the amount of a dopant led to a red-shift of a band gap from 1.33 to 1.18eV. The incorporation of tin into the structure of copper oxide was confirmed by XRD and distribution of tin mapped by EDS analysis. The good catalytic properties of the as-prepared doped material were demonstrated by the enhanced catalytic removal of Rhodamine B in the presence of H2O2. The undoped CuO nanosheets reached only 24% efficiency in the removal of Rhodamine B within two hours. The best result exhibited CuO_050Sn sample containing 4at.% of tin and the degradation of Rhodamine B reached 99% within the same time. We have demonstrated a simple, scalable process for the preparation of catalytically very active Sn-doped CuO nanoparticles with varying properties.

Direct titration with NaOH was used to quantify the acidic functional group content in graphene oxide (GO). Three different methods were used to evaluate the experimental data: the first derivation of the titration curve, Gran linearization and an empirical approach suggested by Ritchie and Perdue for the evaluation of the titration data for humic substances. Two types of acidic functional groups were identified and classified, more or less arbitrarily, as being either carboxylic or phenolic. Typically, the carboxylic acid group contents ranged from ca. 0.80 to 1.70 mmol/g, except for the carboxylated GO prepared by the reaction with chloroacetic acid, which contained significantly more carboxylic acid groups. The titration results are consistent with those obtained by instrumental methods such as X-ray diffraction (XRD), infrared spectroscopy (IR), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). For modelling purposes (proton binding and metal binding), a bimodal continuous distribution model was proposed, and its parameters were estimated from the titration data.

The study reported herein describes for the first time a method for producing defect-free graphene directly from its mineral ore. This was achieved by treating graphite ore in an ionic liquid containing biphasic solvent system, applying pressurized intense cavitation ultrasound. Without any graphite ore pre-treatment, large few layer thick graphene sheets, as well as micrometric layered crumpled graphene structures, were produced. This opens new opportunities for the development of graphene-based technologies.

A graphene oxide-mesoporous birnessite-type δ-MnO 2 nanocomposite (GO-MnO 2 ) was prepared by thermal hydrolysis of suspension potassium permanganate (KMnO 4 ), 2-chloroacetamide and with graphene oxide (GO) in aqueous solution. The prepared nanocomposites samples were characterized by Brunauer–Emmett–Teller surface area (BET) and Barrett–Joiner–Halenda porosity, X-ray Diffraction (XRD), high-resolution scanning electron microscopy (HRSEM) and high-resolution transmission electron microscopy (HRTEM) with energy dispersive x-ray spectroscopy (EDS) for create the map of elements. The degradation activity of the prepared samples was assessed from the kinetics of the stoichiometric degradation of parathion methyl (PM) in the polar solution (acetonitrile). It was shown that prepared samples were effective in decomposition of PM by cleavage of the P-O-aryl bond in the pesticide molecule. The degradation mechanism for PM on the GO-MnO 2 surfaces was proposed.

Here we report a novel method of intercalation of a quaternary ammonium salt bearing a polymerizable group in between graphite galleries. By the exfoliation of the intercalate during its subsequent polymerization with n-butyl methacrylate, a polymer membrane with homogenously dispersed graphene nanostructures was obtained.

Hydrothermally obtained mesoporous ceria-titania mixed oxides with different composition are modified with copper using incipient wetness impregnation and “chemisorption-hydrolysis” techniques. Their catalytic properties in methanol decomposition as a source of hydrogen and total oxidation of ethyl acetate as representative volatile organic pollutant are investigated. The effect of support composition and modification method on the formation of catalytic active sites is studied. The obtained results show that the catalytic behavior is determined by the activity of finely dispersed CuO crystallites and facile electron transfer in the “conjugated” Ti Ce Cu redox centres in the interface layer. The mechanism of the formation of the interface layer and the growth of CuO crystallites during different modification procedures are discussed in details. The mesoporous Cu Ce Ti oxides demonstrate excellent catalytic activity in total oxidation of ethyl acetate. Their catalytic behavior in methanol decomposition is strongly influenced by the reductive transformations, which are provoked by the reaction medium.

Irena R Štenglová Netíková,1 Luboš Petruželka,2,3 Martin Štastný,1,2 Václav Štengl1 1Department of Oncology, 1st Faculty of Medicine, Charles University and General University Hospital in Prague, Prague, Czech Republic; 2Department of Material Chemistry, Institute of Inorganic Chemistry ASCR v.v.i., Rež, Czech Republic; 3Faculty of Environment, J.E. Purkyne University in Ústí nad Labem, Ústí nad labem, Czech Republic Introduction: Macrocrystalline oxides of alkaline earth metals (Mg and Ca) or light metals (Al and Ti) can respond to standard warfare agents such as sulfur mustard, soman, or agent VX. In this paper, we compared the decontamination ability of sodium hydroxide (NaOH) and sodium hypochlorite (NaClO) for nitrogen mustards (cyclophosphamide [CP] and ifosfamide [IFOS]) with a new procedure using a destructive sorbent based on nanocrystalline and nanodispersive titanium dioxide (TiO2) as a new efficient and cheap material for complete decontamination of surfaces.Methods: Titanium (IV) dioxide nanoparticles were prepared by the homogeneous hydrolysis of titanium(IV) oxysulfate (TiOSO4) with urea. The as-prepared TiO2 nanoparticles were used for the fast and safe decontamination of cytostatics from the nitrogen mustard family (CP and IFOS) in water. The adsorption–degradation process of cytostatics in the presence of TiO2 was compared with decontamination agents (0.01 M solution of sodium hydroxide and 5% solution of sodium hypochlorite). The mechanism of the decontamination process and the degradation efficiency were determined by high-performance liquid chromatography with mass spectrometry.Results: It was demonstrated that a 0.01 M solution of sodium hydroxide (NaOH) decomposes CP to 3-((amino(bis(2-chloroethyl)amino)phosphoryl)oxy)propanoic acid and sodium hypochlorite formed two reaction products, namely, IFOS and 4-hydroxy-cyclophosphamide. IFOS is cytotoxic, and 4-hydroxy-cyclophosphamide is a known metabolite of CP after its partial metabolism by CYP/CYP450. IFOS degrades in the pres¬ence of NaOH to toxic IFOS mustard. Titanium(IV) dioxide nanoparticles adsorbed on its surface CP after 5 minutes and on IFOS after 10 minutes. The adsorption–degradation process of CP in water and in the presence of TiO2 led to 4-hydroxy-cyclophosphamide and IFOS, respectively, which decayed to oxidation product 4-hydroxy-ifosfamide.Conclusion: Nanodispersive TiO2 is an effective degradation agent for decontamination of surfaces from cytostatics in medical facilities. Keywords: cyclophosphamide, ifosfamide, ifosfamide mustard, titanium(IV) dioxide, degradation, decontamination agents

COUNTERFOG is a new, rapid response system for collapsing all kinds of dispersed agents (smoke, fog, spores, etc.) by using a fog made of a solution that could eventually contain any kind of neutralizing component. It will be a permanent installation in large public buildings like railway stations or critical infrastructure but also a portable COUNTERFOG for use outdoors, used to counteract a CBRN attack in its earliest stages, greatly reducing the number of potential fatalities. In fact, COUNTERFOG uses the same “weapon” as a CBRN attack: a dispersed state with a large surface/volume ratio. Under certain conditions, it can penetrate all the intricate holes CBRN agents are able to infiltrate. As it needs a minimum quantity of decontaminant, it is intrinsically an environment-friendly and electric-compatible system. It has several benefits: firstly, to neutralize and collapse the CBRN cloud quickly limiting its extension and, secondly, to rapidly decontaminate all the affected area and any equipment. Prototypes have been developed and tested with agent surrogates in a specifically developed Fog Dynamics Laboratory. The results show that COUNTERFOG is effective against chemical, biological, and radiological surrogates and has a potential to be used both to counteract and to decontaminate. This work has been funded by FP7-SEC-2012-1 program of the EU Commission under grant number 312804.

Manganese(IV) oxide used for degradation of toxic organophosphorus compounds was prepared by homogeneous hydrolysis of potassium permanganate (KMnO4) with 2-chloroacetamide. The prepared sample was characterized by X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy, and nitrogen physisorption. The degradation efficiency was determined with parathion methyl (PM) as representative of organophosphate pesticides using high-performance liquid chromatography. For a comparison, the commercially obtained product and the two synthesized manganese(IV) oxides prepared by direct reaction of manganese(II) sulfate (MnSO4·H2O) and potassium permanganate (KMnO4) and potassium permanganate (KMnO4) with urea in aqueous solution were tested. The sample prepared by homogeneous hydrolysis of KMnO4 with 2-chloroacetamide showed the highest degradation efficacy. The reaction half-time in non-polar organic solvent (n-heptane) was around 0.9 min with the degradation efficiency of about 90 % within 2 h. It was shown that comparative samples of manganese(IV) oxides were variously effective in decomposition of PM by cleavage of the P–O-aryl bond in the pesticide molecule. The degradation mechanism for PM on the MnO2 surfaces was proposed.

New composite nanomaterials of cellulose, chitin, and chitosan modified with titanium or nickel nanoparticles were developed and tested for removal of 137Cs, 85Sr, 60Co, and 152+154Eu from aqueous solutions. The composite nanomaterials were characterized by X-ray diffraction, high-resolution scanning electron microscopy, infrared spectroscopy, and nitrogen adsorption–desorption isotherms. The influencing factors of metal adsorption were investigated, including contact time, pH, and metal ions concentration. Freundlich and Langmuir models were applied to fit the Sr(II) equilibrium adsorption data. All Ti modified biopolymers are promising adsorbents for 85Sr, 60Co, and 152+154Eu removal from radioactive wastewater.

A series of multi-component materials on the base of titania doped with niobium, copper and/or cobalt oxides was prepared and tested as catalysts for the total oxidation of ethyl acetate. The obtained materials are characterized by a complex of various physicochemical techniques, such as atomic absorption spectroscopy, nitrogen physisorption, XRD, UV–Vis, FTIR, temperature programmed reduction with hydrogen and compared with the corresponding analogues supported on conventional silica. Both TiO2 and TiO2–Nb2O5 supports improve the synergistic effects in copper and cobalt bi-component modifications as compared to the conventional silica support, which is induced by their strong interaction with loaded active species.

Two series of ceria zirconia mixed oxide samples with wide variation in the composition were synthesized using homogeneous precipitation with urea and template-assisted hydrothermal procedures. The samples were characterized by nitrogen physisorption, XRD, SEM, Raman, XPS, UV-vis, FTIR, pyridine-FTIR and TPR techniques. The catalytic activity in ethyl acetate total oxidation as a representative of VOCs was tested. The effect of preparation procedure on the texture, structure, morphology, acidic and redox properties was discussed in details in close relation with mixed oxides composition and possibilities for fine tuning of their catalytic activity. As compared to urea procedure, the hydrothermal treatment provides more homogeneous insertion of Zr ions within cubic ceria lattice even at high Zr content. As a result higher degree of distortion of the cubic lattice, creation of Ce3+ and oxygen vacancies and an increase in both Lewis acidity and redox ability is observed and these properties are not affected by the presence of template during the synthesis. The differences in the redox and surface acidic properties of both series of materials probably promote the realization of the catalytic process by various reaction pathways and thus influence in a complex way the catalytic activity and selectivity. (C) 2015 Elsevier B.V. All rights reserved.

Titania-iron mixed oxides with various Ti:Fe ratio were prepared by homogeneous hydrolysis of aqueous solutions of titanium(IV) oxysulphate and iron(III) sulphate with urea as a precipitating agent. The synthesized samples were characterized by X-ray diffraction, Raman and infrared spectroscopy, scanning and transmission electron microscopy, XRF analysis, specific surface area (BET) and porosity determination (BJH). These oxides were used for degradation of organophosporus pesticide parathion methyl. The highest degradation efficiency approaching

We present a new, simple, quick and ecologically friendly method of exfoliating graphite to produce graphene. The method is based on the intercalation of a permanganate M2MnO4 (M = K, Na, Li), which is formed by the reaction of a manganate MMnO4 with an alkali metal hydroxide MOH. The quality of exfoliation and the morphology were determined using X-ray photoelectron spectroscopy, X-ray diffraction and microscopic techniques, including transmission electron microscopy and atomic force microscopy. We observed that a stable graphene suspension could be prepared under strongly alkaline conditions in the presence of permanganate and ultrasound assistance. The use of only an alkaline environment for the direct preparation of graphene from graphite structures has not been previously described or applied. It was found that such a method of preparation leads to surprisingly high yields and a stable product for hydrophilic graphene applications.

Nanostructured TiO{sub 2} and mixed oxides of Ti and Fe, Hf, In, Mn or Zr -were prepared by homogeneous hydrolysis of aqueous solution of metal sulphates with urea. The oxides were characterised by X-ray powder diffraction (XRD), scanning electron microscopy, particle size distribution, surface area and porosity. The oxide materials consists of a few nanometre primary crystals (mainly anatase) arranged in a few micrometre regular spherical agglomerates with specific surface area 133–511 m{sup 2} g{sup −1}. The FTIR diffuse spectroscopy was used for monitoring chemical degradation of trimethylphosphate (TMP) as a surrogate for organo-phosphorus pesticides under ambient and higher temperatures. Undoped TiO{sub 2} and Ti,Mn-mixed oxide were most active in cleavage (hydrolysis) of CH{sub 3}O from TMP at room temperature and 100 °C. Cleavage of CH{sub 3}O in the other studied mixed oxides was not complete until temperature exceeds the boiling point of TMP.

Natural raw mineral tungstenite (WS2) was exfoliated to single-layer sheets using high intensity ultrasound. Exfoliation of bulk layered materials, such as WS2 by ultrasound is an attractive way to a large-scale preparation of mono- or few-layered crystals. To evaluate the quality of delamination, X-ray diffraction, Raman spectroscopy and microscopic techniques (TEM and AFM) were employed. The obtained exfoliated product served as a precursor for quantum dot preparation using simple refluxing in ethylene glycol. The synthesized WS2 quantum dots were characterized by photoluminescence spectroscopy and AFM microscopy. Exfoliated WS2 can thus join the group of similarly prepared single-layers of MoS2 or graphene.

Zinc–bismuth oxide–peroxide (ZnO∗ ZnO 2 ∗ Bi 2 O 3 ) nanorod-like particles were prepared for photocatalytic application by the thermal hydrolysis of a zinc–peroxyl-complex precursor. Bi 3 + doping has a strong effect on the morphological structure of the resulting product: lower Bi 3 + concentrations preferentially form nanorods, whereas higher Bi 3 + concentrations preferentially form a flower-like morphology. The synthesised samples of zinc–bismuth oxide–peroxides were examined by X-ray diffraction, Raman spectroscopy, UV–Vis diffuse reflectance spectroscopy, scanning electron microscopy and nitrogen adsorption–desorption isotherm analysis. Electron spin resonance (ESR) was used to monitor the hydroxyl radicals HO on the zinc surfaces. The photocatalytic activity of the prepared samples was determined under the photocatalytic decomposition of Orange II dye in an aqueous slurry under UV or visible light irradiation. The best photocatalytic activity was achieved for the sample denoted ZnP175Bi_400, which includes 45.4 wt.% Bi 2 O 3 . The annealing of the samples at 400 °C increased the photocatalytic activity, mainly in the visible region.

Synthesis The method of homogeneous hydrolysis of Fe, Co, Cr, Ni, Mn, Ti, Al, and Zn salts with urea in aqueous solutions in the presence of substrates (kaolin, metakaolin and mullite) was used for the preparation of composite pigments. In these composites individual kaolinite platelets were covered by a thin layer of hydroxide or oxy-hydroxides of selected metals, which were transformed into a metal oxide layer strongly bond to the aluminosilicate surface by heat treatment. An analogous method, homogeneous hydrolysis of thioacetamide in the presence of Cd and Zn salts was used for pigments based on sulphides. Characterization The mineralogical composition of the pigments was identified by X-ray powder diffraction (XRD), the particle morphology was studied by transmission electron microscopy (TEM) and the color was characterized in CIEL*a*b colours coordinates. Results The kaolin and metakaolin coated with layer of metal oxides are interesting new composite materials, obtained by a very simple preparation process at a low cost.

Monolayer nanosheets of h-BN and h-BCN were prepared by high intensity ultrasound in a pressurized batchreactor. Exfoliation of bulk layered materials using ultrasound is an attractive route to large-scale preparation ofmonolayer crystals. To evaluate the quality of exfoliation and structural properties, XRD, XPS, SAED, BET andporosity, and microscopy techniques (HRTEM, AFM) were employed. The diffuse IR and Raman spectroscopywere used to determine spectral properties. Thus, the prepared monolayer nanosheets served as a precursor forthe synthesis of strong luminescent quantum dots. The BN Quantum Dots (BN-QDTs) and BCN Quantum Dots(BCN-QDTs) were characterized by AFM, photoluminescence spectroscopy and AFM particle size analysis.Our easy preparation lead to the production of very strong blue–green luminescent quantum dots.KEYWORDS: Ultrasound, Exfoliation, BN, BCN, Quantum Dots. 1. INTRODUCTION Mechanicalexfoliation,calledthe‘Scotchtapemethod,’ 1 was the first method used for the preparation of single-layer graphene from natural graphite. By this princi-ple other layered materials similar to graphene weresubsequently exfoliated, so-called inorganic analogues ofgraphene (IAG), such as MoS

Cerium dioxide was used for the first time as reactive sorbent for the degradation of the organophosphate pesticides parathion methyl, chlorpyrifos, dichlofenthion, fenchlorphos, and prothiofos, as well as of some chemical warfare agents-nerve gases soman and O -ethyl S -[2-(diisopropylamino) ethyl] methylphosphonothioate (VX). CeO 2 specimens were prepared by calcination of basic cerous carbonate obtained by precipitation from an aqueous solution. The CeO 2 samples containing certain amounts (1 wt.%-5 wt.%) of the neighboring lanthanides (La, Pr, Nd) were prepared in a similar way from pure lanthanide salts. It was shown that ceria accelerated markedly the decomposition of parathion methyl causing the cleavage of the P-O-aryl bond in the pesticide molecule. A similar reaction mechanism was proposed for the degradation of other organophosphate pesticides and nerve agents. The degradation times (reaction half-times) were in an order of minutes in the presence of CeO 2 , compared to hours or days under common environmental conditions. The reaction in suitable organic solvents allowed conversions of about 90% for parathion methyl loading of 20 mg pesticide/g CeO 2 within 2 h with a reactant half-life in the order of 0.1 min. The key parameter governing the degradation efficiency of CeO 2 was the temperature during calcination. At optimum calcination temperature (about 773.15 K), the produced ceria retained a sufficiently high surface area, and attained an optimum degree of crystallinity (related to a number of crystal defects, and thus potential reactive sites). The presence of other lanthanides somewhat decreased the reaction rate, but this effect was not detrimental and permitted the possible use of chemically impure ceria as a reactive sorbent. A fast organophosphate degradation was demonstrated not only in non-polar solvents (such as heptane), but also in polar aprotic solvents (acetonitrile, acetone) that are miscible with water. This opens new possibilities for designing more versatile decontamination strategies. The cleavage of phosphate ester bonds is of a great importance not only for the degradation of dangerous chemicals (chemical weapons, pesticides), but also for interactions of ceria (especially the nano-sized one) in biologically relevant systems.

Highly photoactive anatase and rutile modifications of titania were prepared by annealing the product of thermal hydrolysis of titania peroxo-complexes under different atmosphere (hydrogen, nitrogen, and oxygen) at 950 °C. The prepared samples were characterized by X-ray powder diffraction, X-ray photoelectron spectroscopy, Raman spectroscopy, electron spin resonance, scanning electron microscopy, and Brunauer–Emmett–Teller surface area and porosity measurement. The individual samples differ with phase composition (ratio of anatase and rutile) and color that determines the rate of reduction of TiO2 and is for reduced form of TiO2 characterized. The UV/Vis diffuse reflectance spectroscopy was employed to estimate band-gap energies. Annealed samples were deposited as a 300 μm thick layer on a glass plate (10 cm × 15 cm) for assessment of the kinetics of a photocatalytic degradation of butane in a gas phase.

An environmentally benign synthesis method was used to prepare a nearly uniform dispersion of TiO2 nanoparticles modified by bismuth for photocatalytic purposes. The role of bismuth in the catalyst structure was evaluated using numerous methods such as XRPD, HTXRPD, TEM and HRTEM, and XPS, as well as Raman, FTIR, and UV–Vis spectroscopy. The bismuth doping significantly improved the photocatalytic performance of azo dye RB5 discoloration due to the formation of surface Bi3+ species and the abundant hydroxylation of the catalyst surface. The great advantage of this procedure lies in the low temperature preparation under ambient pressure without use of the titanium organometallic precursors. Therefore, this developed synthesis procedure could be easily adapted to the industrial scale.

A new, advanced graphene oxide based material modified with the extremely stable o-carboranoyl 1,2-C2B10H11 unit was created. The carboranoyl-functionalized graphene oxide was synthesized from Li[1,2-C2B10H11] and COCl-functionalized graphene-oxide, which was prepared by converting the graphene oxide –COOH groups to COCl with SOCl2. The carboranoyl-functionalized graphene oxide was characterized using infrared and X-ray photoelectron spectroscopy. The morphology was investigated via transmission, scanning electron, and atomic force microscopies. The electrochemical properties of o-carboranoyl functionalized graphene oxide was studied using cyclic voltammetry, electrochemical impedance spectroscopy and electric force microscopy. This new graphene-based material could in future be used as a precursor for conductive self-assembled monolayers.

This work describes a straightforward procedure for the preparation of graphene by opening multi-walled carbon nanotubes (CNT), using ionic liquids (IL) as lubricating and stabilizing agents. The sequential application of vacuum and sonication allows the successful opening and unrolling of the CNT, and the final nanocarbon morphology is IL-dependent. This enabled the preparation of epoxy-based nanocomposites with morphologically distinct carbon nanofillers. The CNT–IL mixtures and nanocomposites obtained were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), atomic force microscopy (AFM) and Raman spectroscopy.

This study examines the photocatalytic activity of coatings produced by atmospheric plasma spraying (APS). The applied spraying tools were gas-stabilized (GSP) and water-stabilized (WSP) plasma guns. The TiO 2 –Fe 2 O 3 powder with and without Na 2 SiO 3 additive was produced as agglomerates suitable for feeding into the plasma jet. The coatings are analyzed by scanning electron microscopy, X-ray fluorescence and X-ray diffraction. Photocatalytic degradation of butane under UV and under visible light, as well as the growth kinetics of the products – carbon dioxide and carbon monoxide – is quantified for all coatings and compared with a pure TiO 2 coating. The coatings show a lamellar structure, as it is typical for this process. However, their porosity is rather high. Anatase titania from the feedstock powder is converted into rutile phase in all coatings; whereas the presence of FeTiO 3 is detected in the coating without Na 2 SiO 3 made by WSP and metallic iron in the GSP coating. The coating from powder with Na 2 SiO 3 admixture is partly amorphous. This coating is photocatalytically active especially under UV, whereas under visible light it is overcome by the WSP coating. The GSP coating has the best photocatalytic activity under both different radiations.

We report on a new method for synthesising strongly blue and green photoluminescent graphene quantum dots (GQDs). Graphene was prepared by a new feasible method using an intensive cavitation field in a pressurised ultrasonic batch reactor. The prepared graphene was quantitatively converted to graphene oxide using our modified, safer Hummer’s method. Graphene oxide was characterised by microscopic (AFM and TEM) and spectral (infrared and Raman) methods, and the thermal stability of graphene oxide was determined using thermal analysis (DTA-TG). GQDs were prepared by a one-pot reaction, refluxing graphene oxide in different solvents (ethylene glycol, polyethylene glycol, dimethylformamide, dimethyl sulfoxide and N-methyl-2-pyrrolidone) at atmospheric pressure. The synthesised GQDs were characterised by infrared, UV–Vis absorption and photoluminescence spectroscopy, X-ray photoelectron spectroscopy (XPS) and AFM microscopy.

Rutile TiO2 and Eskolaite Cr2O3 powders were mechanically mixed and fed into the plasma jet simultaneously. The influence of the ratio of components on behavior of the plasma-sprayed coatings was observed using two different compositions, both at two different feeding distances. The produced coatings were analyzed by XRD, SEM, XPS, and light microscopy. Electrical resistivity was measured at voltages from 1 to 100 V. Photocatalytic decomposition of butane on the coatings was studied using visible light together with a setup typically used for UV-light tests. For the coatings with high TiO2 content, besides rutile, low anatase content was identified. The coatings with predominant Cr2O3 exhibited lower porosity and higher hardness. All coatings are relatively efficient photocatalysts for butane decomposition. Moreover, they have good mechanical properties governed predominantly by Cr2O3 content as the harder component. It was proven that the spray process led to obtaining of robust photocatalytically active coatings.

We report on the characterization, phase stability, surface chemical andphotocatalytic properties of Zr and Y co-doped anatase TiO2 nanoparticles prepared by homogenous hydrolysis methods using urea as precipitating agent. The materials were analyzed by scanning electron microscopy, X-ray diffraction, Raman spectroscopy, BET isotherm and BJH pore size distribution measurements. It is shown that Y and Zr ions replace Ti ions in the anatase TiO2 structures up to a critical total dopant concentration of approximately 13 wt%. The co-doped particles show increased phase stability compared to pure anatase TiO2nanoparticles. The anatase to rutile phase transformation is shown to be preceded by cation segregation and dissolution with concomitant precipitation of Y2Ti2-xZrxO7 and ZrTiO4. Co-doping modifies the optical absorption edge with a resulting attenuation of the Urbach tail. The band gap is slightly blue-shifted at high doping concentrations, and red shifted at lower doping concentrations. Formic acid adsorption was used as a probe molecule to investigate surfacechemical properties and adsorbate structures. It was found that the relative abundance ofmonodentate formate compared to bidentate coordinated formate decreases with increasing doping concentration. This is attributed to an increased surface acidity with increasing dopant concentration. Photodegradation of formic acid occurred on all samples. With mode-resolved in situ FTIR spectroscopy it is shown that the rate of photodegradation of monodentate formate species are higher than for bidentate formate species. Thus our results show that the trend ofdecreasing photo-degradation rate with increasing dopant concentration can be explained by the adsorbate structure, which is controlled by the acidity of the surface.

We present a procedure for removal and detoxification of chemical warfare agents (CWA) from corrosion- sensitive components using their reactive sorption (adsorption and bond cleavage). The procedure consists of spraying a suspended sorbent over a contaminated surface followed by mechanical removal of the spent sorbent after liquid phase evaporation. The procedure was tested using a video graphics array (VGA computer card) VGA card, sulfur mustard (yperite, HD agent, bis(2-chloroethyl)sulfide), and Zr 4+ -doped TiO2 sorbent obtained by homogeneous hydrolysis. After 60 min of interaction with a suspension of the reactive sorbent with the contaminated VGA card, 99.3% of the sulfur mustard was removed, while the VGA card retained its functionality. The procedure does not require specialized instrumentation. This is feasible for electronic devices, as they do not need corrosive and electrically conducting agents or nonvolatile solvents that would harm electronic circuits. The method would be applicable to decontamination of a broad range of CWAs and pesticides.

Metal oxides have very important applications in many areas of chemistry, physics and materials science; their properties are dependent on the method of preparation, the morphology and texture. Nanostructured metal oxides can exhibit unique characteristics unlike those of the bulk form depending on their morphology, with a high density of edges, corners and defect surfaces. In recent years, methods have been developed for the preparation of metal oxide powders with tunable control of the primary particle size as well as of a secondary particle size: the size of agglomerates of crystallites. One of the many ways to take advantage of unique properties of nanostructured oxide materials is stoichiometric degradation of chemical warfare agents (CWAs) and volatile organic compounds (VOC) pollutants on their surfaces.

Substituted iron(III)–manganese(III, IV) oxides, ammonio-jarosite and birnessite, were prepared by a homogeneous hydrolysis of potassium permanganate and iron(III) sulphate with 2-chloroacetamide and urea, respectively. Synthesised oxides were characterised using Brunauer–Emmett–Teller (BET) surface area and Barrett–Joiner–Halenda porosity (BJH), X-ray diffraction (XRD), infrared spectroscopy (IR), Raman spectroscopy and scanning electron microscopy (SEM). The oxides were taken for an experimental evaluation of their reactivity against sulphur mustard (HD) and soman (GD). When ammonio-jarosite formation is suppressed by adding urea to the reaction mixture, the reaction products are mixtures of goethite, schwertmannite and ferrihydrite, and their degradation activity against soman considerably increases. The best activities for the degradation of sulphur mustard (97.9% in 64 min) and soman (97.9% in 64 min) were observed for FeMn_75 with 32.6 wt.% Fe (36.8 wt.% Mn) and FeMn_37U with 60.8 wt.% Fe (10.1 wt.% Mn) samples, respectively.

Manganese(IV) oxides were prepared by homogeneous hydrolysis of potassium permanganate with 2-chloroacetamide and direct reaction of potassium permanganate with manganese(II) sulfate in aqueous solutions. Synthesized manganese(IV) oxides were characterized using Brunauer–Emmett–Teller (BET) surface area and Barrett–Joiner–Halenda porosity (BJH), X-ray diffraction (XRD), infrared spectroscopy (IR), and scanning electron microscopy (SEM). These oxides were taken for an experimental evaluation of their reactivity with sulfur mustard (HD or bis(2-Chloroethyl)sulfide), soman (GD or (3,3′-dimethylbutan-2-yl)-) and VX agent (S-[-(diisopropylamino)ethyl]-O-ethyl-methylphosphonothionate). The degree of conversion for sulfur mustard and agent VX is very good for both samples and come up to 95% and 99%, respectively. In the contrast to sulfur mustard and agent VX, degradation of soman was only 56% of the cryptomelane-type MnO2 and 18% of the birnessite-type MnO2.

The influence of input power on plasma sprayed coating was studied for a water-stabilized plasma spray torch (WSP®) and ceramic coatings formed from titanium dioxide (TiO2). All other spray setup parameters were secured during the experiment with electric supply power as the only variable factor. Physical characteristics of the coatings were tested by means of Raman spectroscopy and X-ray photoelectron spectroscopy which are able to determine the stoichiometry and surface chemical composition of the coatings. Further, stoichiometry and surface states are crucial for the photocatalytic efficiency of the coatings. The photocatalytic procedure involved was UV-induced decomposition of acetone. Links between the tested features are drawn. The lower supply power used during the spraying of TiO2 coating resulted in higher activity with respect to the photocatalytic point of view. Both the stoichiometry and surface composition are in the same time deviated from pure TiO2.