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The development of CdS-based photocatalysts with the appropriate bandgap structure, impressive optical response, and long-lasting reusability is both crucial and challenging. The heterogeneous catalyst, made up of polytriazine and CdS, demonstrates exceptional photogenerated charge separation and transfer capabilities, as well as superior CO2 adsorption abilities. In this study, we have shown that the CO2 photoassisted reduction efficiency of CdS nanosheets can be significantly improved through surface modification with a polytriazine polymer coating. The PP@CdS photocatalyst has been thoroughly characterized using techniques such as XRD, TEM, SEM, N2 adsorption-desorption, CO2 adsorption, DRS, XPS, and photoelectric performance tests. The catalytic performance of the PP@CdS was assessed through photoassisted CO2 reduction reactions under visible light irradiation in an aqueous medium at 25 ℃. Owing to its enhanced CO2 adsorption capacity and the efficient separation and utilization of photogenerated electrons, the PP@CdS photocatalyst demonstrated a CO yield (6.7 μmol/g/h) 1.3 times greater and a CH4 yield (4.2 μmol/g/h) 1.3 times higher than that of bare CdS nanosheets. Furthermore, the PP@CdS photocatalyst demonstrated outstanding reusability in CO2 reduction reactions. This study presents a novel approach to enhancing the CO2 adsorption capacity and modulating the bandgap structure of polymer-coated semiconductor materials.

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Copyright of Journal of Shanghai Polytechnic University is the property of Journal of Shanghai Polytechnic University Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In recent years, with the development of nanotechnology, there has been significant progress in the provision and functionalization of nanomaterials based on Ir nanostructures. It is possible to design different Ir-based nanoelectrolysts with improved performance and favorite structure using nanoengineering methods. In this study, porous Ir/Co/NiSe2 nanocages (NCs) were prepared using the sacrificial template approach, ion exchange strategy, and selenization under heat treatment. The designed Ir/Co/NiSe2 NCs were applied to modify the surface of the glassy carbon electrode (GCE) to use as an effective multifunctional electrocatalyst for the O2 and H2 evolution reactions (OER and HER) and glucose oxidation in an alkaline medium. The Ir/Co/NiSe2 NCs/GCE due to the using the advantages of a three-dimensional porous polymetallic hollow nanostructure, including providing high surface area and numerous electrochemical active sites, fast electron/mass transfer, high conductivity, and open channels for effective gas release in the OER and HER reactions, exhibits improved electrochemical performance. The Ir/Co/NiSe2 NCs/GCE delivered a current density of 100 mA cm–2 at 1.55 V for OER and −0.21 V for HER and determined glucose in the linear ranges of 100.0 nM to 2.0 mM and 2.0–17.0 mM with a limit of detection of 30 nM and sensitivity of 4375.8 and 477.7 μA mM–1 cm–2, respectively. [ABSTRACT FROM AUTHOR]

Based on the current situation of antibiotic pollution and the demand of prevention and control, this paper prepared 1 ~4 jjim microspherical CuSe/ZnSe composite photocatalysts by adding Cu to ZnSe through the hydrothermal and basic ion exchange methods・ The sample was characterized by XRD, SEM, XPS and BET, and the photocatalytic properties of the as-obtained CuSe/ZnSe under visible light were investigated with ciprofloxacin(CIP) as the degradation target・ The results showed that the best degradation effect was achieved and the degradation efficiency of CIP reached to 75.5% when the Cu addition was up to 10%. Moreover, the degradation effect of reuse for four cycles was still over 60%, and the degradation process was in accordance with the pseudo primary kinetic model. In the degradation process, the main active species was superoxide radical, which played a key role in the catalytic degradation process. It would provide technical support for broadening the photodegradation application of ZnSe for the removal of antibiotics in the environment. [ABSTRACT FROM AUTHOR]

Copyright of Energy Chemical Industry is the property of Energy Chemical Industry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Hydrometallurgy of China is the property of Hydrometallurgy of China Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Birefringent materials are highly demanded for high‐performance polarized optics. As compared with artificial anisotropic metamaterials, anisotropic crystals have advantages of low optical losses and easy processing, but their birefringence is still limited. Herein, based on first‐principles studies, we identified a new type of functional anion units, (HxC6N9)(3−x)− (x=0, 1, 2), and then successfully synthesized a new anisotropic crystal, namely, CsH2C6N9⋅H2O (I), whose crystal structure consists of (H2C6N9)− anions. Remarkably, I is ultraviolet transparent and exhibits very large birefringence of about 0.55@550 nm, which is much larger than those of commercial birefringent crystals. These results make I a candidate for highly efficient manipulation of optics and light in optical modulation devices. Theoretical calculations reveal that large birefringence mainly arises from the cooperative π orbitals in (H2C6N9)− anions. This work provides a new insight on the underlying structure–property relationships of anisotropic crystals. [ABSTRACT FROM AUTHOR]

HZSM-5 zeolite modified by rare earth was prepared with ion exchange method in the study. The effects of different types of rare earth elements, modification temperatures, pH, and rare earth contents on structural stability of the as-prepared zeolite were investigated. The as-prepared zeolite was characterized by XRD, SEM and FT-IR spectroscopy. The characterization results showed that the crystal structure of the zeolite was not changed by the modification of rare earth, which was evenly distributed on the surface or in the pore channel of zeolite. Sm/HZSM-5 zeolite with the highest structural stability was obtained under the following modification conditions: 2% rare earth Sm, modification temperature of 70 °C, 2 h of ion exchange, and pH 3. [ABSTRACT FROM AUTHOR]

High-purity mesoporous alumina materials were prepared in this study via deep sodium removal with strong acidic cation exchange resin, a recyclable functional material that has strong dissociation ability in acid and alkaline solution for ion exchange. The effects of various conditions on the mass fraction of impurities, surface physical properties, and crystal phase of the products were investigated by XRF, XRD, SEM, EDS, TEM, BET, BJH, and NLDFT methods. When sodium aluminate solution with an initial concentration of 60 g/L was reacted by ion exchange with the resin for 60 min, the seed decomposition time was 48 h, the heating rate was 10 °C/min, and the holding temperature was 500 °C. These conditions produced mass fractions of SiO2, Fe2O3, and Na2O impurities in the alumina material of 0.0045%, 0.0038%, and 0.0166%, respectively. The total impurity removal rate was as high as 99.099%. The specific surface area, pore volume, and pore diameter were 229.4 m2/g, 0.28 cm3/g, and 4.0 nm, respectively, indicating that high-purity mesoporous alumina has high porosity and can be wielded as an adsorbent and catalyst. [ABSTRACT FROM AUTHOR]

Copyright of Journal of South China University of Technology (Natural Science Edition) is the property of South China University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Regenerable ion exchange resin derived magnetic activated carbon (Fe/AC) was prepared to remove mercury from flue gases at 120–180 °C under a high space velocity of 240000 h−1, in this study. The Fe/AC showed higher mercury removal efficiency than those of either magnetic activated carbon without activation or commercial coconut-activated carbon. The optimum temperature for removal of mercury from flue gases was determined to be 120 °C and the existence of SO 2 in flue gases promoted the mercury removal efficiency of Fe/AC. Mercury compounds of HgS (metacinnabar), HgO, HgS (cinnabar) and HgSO 4 were found over spent adsorbents. The HgO was generated through the reaction of mercury with lattice oxygen and chemisorbed oxygen, while the formation of HgS was due to the reaction between mercury, FeS and sulfur over the adsorbent. The lattice oxygen could oxidize SO 2 to SO 3 , which further reacted with mercury to form HgSO 4. The Fe/AC presented excellent regeneration and reuse ability, the mercury removal efficiency of which showed a great increase even after 5 runs of regeneration. The crystalline structure of Fe/AC changed remarkably after regeneration and the FeS over Fe/AC was converted to Fe 3 O 4. The above excellent properties suggest that Fe/AC might be a promising adsorbent to remove mercury from flue gases. • Recyclable magnetic activated carbon was synthesized by ion exchange method. • SO 2 in flue gases promoted the mercury removal capacity of magnetic activated carbon. • Spent magnetic adsorbent could be effectively regenerated by heat treatment. • Spent magnetic adsorbent showed improved mercury removal capacity after regeneration. [ABSTRACT FROM AUTHOR]

Ion exchange method as a green synthesis route is proposed to prepare hydrous ruthenium oxide nanoparticles (H-RuO2). Calcination of H-RuO2 at 350°C resulted in the crystalline rutile RuO2 nanoparticles (C-RuO2). Treatment of H-RuO2 with 20 vol% ammonium hydroxide solution under microwave irradiation and calcination at 350°C resulted in a highly electrocatalytic active crystalline RuO2 nanoparticles (A-C-RuO2). Electrocatalytic performances of H-RuO2, C-RuO2 and A-C-RuO2 for the oxygen evolution reaction in 0.50 mol L−1 H2SO4 medium are evaluated and compared. Improved performances towards the oxygen evolution reaction are observed for A-C-RuO2 when compared to C-RuO2. Based on XRD, TEM, XPS and Raman characterizations performed on all the specimens, it is deduced that the physicochemical properties (crystallinity, mean crystallite size, level of hydrous rutile content) are varied for A-C-RuO2 when compared to C-RuO2. Structure-property correlation has been established to describe the higher electrocatalytic activity of A-C-RuO2.

[Display omitted] • Novel nanocomposite MnTMPyP/LaTa 2 O 7 was synthesized via ion exchange. • The detection limits of MnTMPyP/LaTa 2 O 7 /GCE for AA and UA reached μM level. • The sensor has good electrochemical properties for AA and UA in urine samples. A novel nanocomposite MnTMPyP/LaTa 2 O 7 was synthesized via intercalation of [5, 10, 15, 20-tetrakis (N-methylpyridinium-4-yl) porphyrinato manganese (III) (MnTMPyP) into the laminar structure of RbLaTa 2 O 7 using an ion exchange method. An electrochemical sensor utilizing a MnTMPyP/LaTa 2 O 7 modified glassy carbon electrode (GCE) was employed for the simultaneous detection of ascorbic acid (AA) and uric acid (UA). X-ray diffractometry, Fourier infrared spectroscopy, and transmission electron microscopy were utilized to characterize the structure in this experiment. Differential pulse voltammetry (DPV), electrochemical impedance spectroscopy (EIS), and cyclic voltammetry (CV) were employed to analyze the electrochemical properties. The MnTMPyP/LaTa 2 O 7 /GCE demonstrated a larger electrochemically active area (0.106 cm2), lower charge transfer resistance (43.1 Ω), and enhanced catalytic activity compared to single-component modified electrodes (RbLaTa 2 O 7 /GCE, bare/GCE). The detection limits, within the concentration ranges of 1.25–40.41 μM for AA and 0.62–11.81 μM for UA (S/N = 3), were estimated to be 0.37 μM and 0.44 μM, respectively. MnTMPyP/LaTa 2 O 7 /GCE also exhibits excellent stability, reproducibility, and anti-interference compared to previous literatures. Furthermore, the performance of MnTMPyP/LaTa 2 O 7 /GCE was demonstrated in real urine samples, achieving recoveries between 98.7 % and 103.5 %. The ion exchange provides a simpler method for the preparation of multifunctional electrochemical sensing. [ABSTRACT FROM AUTHOR]

The Cu/SAPO-34 catalysts were prepared via the ion exchange process for achieving improved catalytic activity. Effects of various parameters including copper ions sources, copper ions loadings and ion exchange temperature on catalyst performance of the Cu/SAPO-34 catalysts were investigated. The results showed that the Cu/SAPO-34 catalysts roughly maintained similar cubic-like morphology and crystalline structure with the SAPO-34 catalyst, and achieved enhanced catalytic activity. Among various copper ion sources, the Cu/SAPO-34 catalyst using Cu(CH _3 COO) _2 as copper ion source demonstrated high nitric oxide conversion rate. Increasing the copper ion loadings, the nitric oxide conversion rate of the Cu/SAPO-34 catalysts achieved significant improvement. However, when the copper ion loadings exceeded 0.01 mol, the nitric oxide conversion rate began to decline. The catalytic activity of the Cu/SAPO-34 also closely depended on ion exchange temperature. The nitric oxide conversion rate of the Cu/SAPO-34 catalyst showed a trend of first increasing and then decreasing with the improvement of ion exchange temperature, and the recommended ion exchange temperature was 60 °C. Hydrothermal aging treatment further confirmed the good stability of the Cu/SAPO-34 catalyst. Moreover, kinetic investigation was carried out, which was in agreement with the SCR results.

The aim of this research is to investigate the influence of various ion exchange methods in the assembly of nanostructured kaolin-SAPO-34 catalyst using silica sol as binder by spray drying for conversion of methanol to light olefins in a fluidized bed reactor. Physiochemical properties of the catalysts were identified by XRD, FESEM, EDX, BET, NH3-TPD and FTIR techniques. The results of XRD analysis exhibit typical SAPO-34 and kaolinite phase for all the three spray dried samples. It represents the successful spray drying that the crystallite structure of the shaped samples assumes by the spray dryer that is composed of both kaolinite and SAPO-34 phase. With the comparison of FESEM results of the samples, it can be implied that use of resin as an ion-exchange agent resulted in smoother and larger particles. According to NH3-TPD results at high calcination temperatures, the reaction of silica from the binder with the extra-framework alumina of kaolin or SAPO-34 results in new acid sites. The catalysts mechanical strength was evaluated by the fluidized bed attrition test. MTO Performance tests were carried out to study the activity of the catalysts in a fixed bed reactor. The optimized catalyst was also tested in a fluidized bed reactor. The optimal shaped sample showed excellent activity of near 22 h during MTO reaction in a fluidized bed reactor. [ABSTRACT FROM AUTHOR]

The possibility and effectiveness of removal of phosphate from aqueous solutions with the use of new low-cost synthetic zeolites obtained from fly ash and modified with lanthanum, was studied. Physicochemical properties of the zeolites were characterized by different techniques such as X-ray diffraction, low-temperature nitrogen sorption and scanning electron microscopy. It has been established that lanthanum is preferentially located in the zeolites channels and cages, which is related to the ion-exchange method of modification. Introduction of lanthanum cations leads to a reduction in BET surface area, mainly due to a decrease in the area of micropores and reduction in the pore volume. The key element of the study was a series of tests of phosphate adsorption from aqueous solutions. The efficiency of adsorption process was found to depend on the concentration of adsorbate, pH of its solution and temperature. The sorption capacity of zeolites obtained from fly ashes (La-P1, La-A) towards phosphate was compared with that of a natural zeolite – clinoptilolite, modified with lanthanum (La-CLP). The sorption capacities of the particular samples were as follows: La-P1 – 58.2 mg/g, La-A – 44.0 mg/g and La-CLP – 24.6 mg/g. The experimental data were well fitted by the Langmuir isotherm model. The sorption capacities of all samples towards phosphate increased with temperature increasing from 25 to 60 °C. The values of the thermodynamic parameters ΔH 0 and ΔG 0 revealed that the adsorption was spontaneous and endothermic. [ABSTRACT FROM AUTHOR]

In this study, we employed an in-situ transformation method to prepared a mesoporous spindle like BiVO 4 /nanosheet BiOCl composite photocatalyst. The nanostructure and content of 2-D BiOCl could be facilely tuned by controlling the concentration of Cl − ions in the reaction solution. The as-prepared BiVO 4 -BiOCl photocatalyst showed an excellent photocatalytic norfloxacin degradation performance, and removed it in 1 h almost completely. Further research results indicated that a well-defined p-n heterojunction interface has been formed between BiVO 4 and BiOCl, to enhance the separation efficiency of photogenerated carriers. In addition, after the nanosheets BiOCl interlaced with the mesoporous BiVO 4 spindles, since the 2-D structure of the former, the charge transfer capacity of the composite would be improved to prolong the lifetime of the photoinduced carriers. [ABSTRACT FROM AUTHOR]

In situ cosmogenic 26Al/10Be burial dating, one of the dating methods that has emerged over the past several years, has been widely applied in geomorphology, archaeology and other science disciplines. The chemical recovery and purity of Al is one of the key factors to yield high-precision age results. Further improvements are needed for several steps for separating and purifying Al in the current chemical procedure of Purdue University. Based on results of conditional experiments, this study proposes the following suggestions for refining the procedure: 1) 38-75 μm, instead of 75-150 μm, anion exchange resin should be used to reduce the volume of eluting solution (0.05 mol/L H2C2O4-0.5 mol/L HCl) and to separate Al from its major interference elements of Fe and Ti; 2) Cation exchange resin be used to extract Al from H2C2O4-HCl solution to avoid the time-consuming decomposition of H2C2O4 by chemical reagents. The analyses of simulating samples show that quasi quantitative recovery of Al is realized by using the above two refined steps and the whole procedure recovery of Al reached 91%±5% with a purity of 98%.

Copyright of Industrial Minerals & Processing / Huagong Kuangwu yu Jiagong is the property of Industrial Minerals & Processing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

• Ion exchange strategy is used for the samples preparation. • The closely contacted heterojunction interface will facilitate the electron transport. • The high production rates of CO is obtained. • The selectivity of CO 2 photoreduction is well. CO 2 reduction via photocatalytic is regarded as the excellent strategy to resolve the severe environmental crisis and energy crisis caused by the accelerated utilization of fossil energy like natural gas, oil, and coal. The Ag ion and the Br ion in BiOBr are creatively used in the ion exchange strategy to form AgBr on the surface of BiOBr, and an S-scheme BiOBr/AgBr heterojunction with close interface contact is constructed. The visible light utilization rate and CO 2 conversion rate of the obtained heterojunction are both remarkably improved. The reduction rate of CO 2 over the catalyst was tested under visible light using pure water as the liquid environment. As obtained results displayed that the transformation efficiency of BA-1 to CO from CO 2 in the visible light was 12.43 μ mol g-1h−1, which is about 3 times that the pristine BiOBr. The intermediates during the reaction were studied using in situ DRIFTS. The process by which CO 2 was degraded was speculated based on in situ DRIFTS spectra. In addition, TPR, EIS, and PL measurements indicate that BA-1 has a high solar utilization rate and strong photo-generated carrier transfer and separation capability. This work showed a novel direction for preparation of efficient photocatalyst for CO 2 reduction. [ABSTRACT FROM AUTHOR]

White light emitting YVO 4 :Eu 3+ ,Tm 3+ ,Dy 3+ nanometer- and submicrometer-sized particles were successfully prepared using an ion exchange method. Undoped YVO 4 nanoparticles were firstly synthesized by a solvothermal method, and Eu 3+ , Tm 3+ , and Dy 3+ doping ions were then ion exchanged into these undoped YVO 4 nanoparticles to form the Eu 3+ ,Dy 3+ ,Tm 3+ -codoped YVO 4 nanoparticles. After thermal annealing, the Eu 3+ ,Dy 3+ ,Tm 3+ -codoped YVO 4 particles showed strong luminescence. The Eu 3+ , Dy 3+ , and Tm 3+ dopants emitted red, blue, and green lights, respectively. The doping concentrations of the Eu 3+ , Dy 3+ , and Tm 3+ dopants were optimized for white light emission. X-ray diffraction, transmission electron microscopy, and fluorescence spectroscopy were used to characterize and analyze the white light emitting YVO 4 :Eu 3+ ,Tm 3+ ,Dy 3+ nanometer- and submicrometer-sized particles. [ABSTRACT FROM AUTHOR]

Removal of heavy metals such as Cu(II), Cd(II), Zn(II), Ni(II) and Pb(II) from wastewaters in several industrial areas of Kerman, Iran, was evaluated by using ion-exchange method. Dowex 50WX8 (H) resin was selected as suitable adsorbent for reduction of toxic elements in wastewater. The most effective sorption was observed within in pH between 4-6, fow rate of 4 mL min and amount of 200 mg resin. Sorbent capacities for Cu(II), Cd(II), Zn(II), Ni(II) and Pb(II) were 45; 50; 50; 40 and 60 mg/g respectively. The results determine that exchanger resin is extremely effective in lowering the metal content of wastewaters. [ABSTRACT FROM AUTHOR]

Tb 3+ doped LaF 3 (LaF 3 :Tb 3+ ) is an important green light emitting material, but the low optical absorption cross-section of Tb 3+ ions strongly limits its luminescence properties. In this work, we used an ion exchange method to prepare LaF 3 :Tb 3+ based inorganic–organic hybrid nanostructures, which exhibited strong luminescence as a result of luminescence sensitization, an energy transfer process from the organic ligands to the Tb 3+ ions. The undoped LaF 3 nanoparticles were first synthesized by a simple hydrothermal method, and Tb 3+ ions were then ion exchanged into these LaF 3 nanoparticles to form the LaF 3 :Tb 3+ nanoparticles, which were then used to prepare the inorganic–organic hybrid nanostructures with benzoic acid. The LaF 3 :Tb 3+ based inorganic–organic hybrid nanostructures had an emission intensity more than 44 times stronger than the as-prepared LaF 3 :Tb 3+ nanoparticles. Dependence of their luminescence on the Tb 3+ doping concentration and amount of organic ligands was studied in detail. [ABSTRACT FROM AUTHOR]

A series of urchin-like CdS/ZrO nanocomposites with different mole ratios of Cd/Zr were prepared by a two-step method combining the microwave-assisted hydrothermal and ion exchange methods. The products were characterized by X-ray diffraction, ultraviolet-visible diffuse reflectance spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, and N adsorption-desorption measurements. The results of the study revealed that the CdS/ZrO nanocomposites had mixed phases of tetragonal ZrO and hexagonal CdS. Moreover, the samples prepared by the microwave-assisted hydrothermal method possessed the urchin-like structure with a surface composed of protrude-like nanoparticles in large quantities. The absorption in the visible region changed slightly with increasing mole ratio of Cd/Zr. Moreover, compared to the nanocomposites prepared by the conventional heating, the nanocomposites prepared by the microwave-assisted hydrothermal synthesis showed significantly different Brunauer-Emmett-Teller values, and the urchin-like CdS/ZrO structures were obtained. The photocatalytic degradation of methyl orange under ultraviolet (UV) light irradiation indicated that the photocatalytic activity of the CdS/ZrO nanocomposite with CdS/ZrO molar ratio of 30 % was higher than those of CdS, ZrO, and other different ratios of CdS/ZrO nanocomposites. Moreover, under UV light, visible light, and microwave-assisted multimode photocatalytic degradation, the urchin-like CdS/ZrO nanocomposites significantly affected the photodegradation of various dyes. To understand the possible reaction mechanism of the photocatalysis by the CdS/ZrO nanocomposites, a series of controlled experiments were performed, and the stability and reusability of the CdS/ZrO nanocomposites were further investigated by the photocatalytic reaction. [ABSTRACT FROM AUTHOR]

Abstract: In the present manuscript we report about the preparation of CdS/CuInSe2 heterojunction thin films by chemical ion exchange method and investigation of 120MeV Au9+ swift heavy ions (SHI) irradiation effect on its physicochemical as well as optoelectronic properties. These pristine (as grown) samples are irradiated with 120MeV Au9+ SHI of 5×1011 and 5×1012 ions/cm2 fluencies and later on characterized for structural, compositional, morphological, optical and I–V characteristics. X-ray diffraction (XRD) pattern obtained from pristine and irradiated films shows considerable modifications in peak intensity as well as rising of some new peaks, corresponding to In2Se3, Cu3Se2 and CuIn2Se3 materials. Transmission electron microscope (TEM) images show decrease in grain size upon increase in irradiation ion fluencies, which is also supported from the observation of random and uneven distribution of nano-grains as confirmed through scanning electron microscope (SEM) images. Presence of Cd, Cu, In, S and Se in energy dispersive X-ray spectrum analysis (EDAX) confirms the expected and observed elemental composition in thin films, the absorbance peaks are related to band to band transitions and spin orbit splitting while energy band gap is observed to increase from 1.36 for pristine to 1.53eV for SHI irradiated thin films and I–V characteristics under illumination to 100mW/cm2 light source shows enhancement in conversion efficiency from 0.26 to 1.59% upon irradiation. [Copyright &y& Elsevier]

Sulfonated poly(arylene ether sulfone) (SPAES)/sulfonated montmorillonite (SMMT) hybrid membranes were fabricated to evaluate their potential for use as direct methanol fuel cells (DMFCs). To minimize the loss of proton conductivity while reducing methanol permeability, an ion exchange method was used to prepare the SMMT including a sulfonic acid group. The SPAES/NMMT(-Na) and SPAES/SMMT(-SOH) hybrid membranes were prepared using a solution casting and evaporation method, and the NMMT/SMMT content in the composite membranes was controlled at 0.5-2.0 wt% based on the SPAES. The performances of the hybrid membranes for the DMFCs in terms of their mechanical and thermal properties, water uptake, water retention, methanol permeability, and proton conductivity were investigated. The mechanical and thermal properties of the SPAES membranes were improved with introduction of the NMMT and SMMT. Methanol permeability reduction was also obtained when the SMMT content and the sulfonation degree increased. The SPAES/SMMT composite membrane showed increased proton conductivity compared with the non-modified MMT composite membrane under the 100% relative humidity condition. As the modified MMT content increased, the proton conductivity increased and the methanol permeability decreased due to the monovalent ions located between the MMT layers. The ratio of methanol permeability to proton conductivity for the SPEAS/SMMT (2.0 wt%) composite membrane was higher than that of Nafion® 1135. This property makes hybrid membranes potential candidates for DMFC applications. [InlineMediaObject not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Abstract: Cu/HMS catalysts synthesized with different copper precursors via the ion exchange method have been systematically characterized, focusing on the influence of copper precursors. It is found that the texture, surface composition and the surface structure of the dried, calcined and reduced Cu/HMS materials were profoundly affected by the kinds of copper precursors. Based on the characterizations, the copper species on dried, calcined and reduced samples were assigned. Proper copper precursor could be beneficial for the generation of active copper species; enhanced catalytic performance could thus be obtained. By optimizing the gas-hydrogenation reaction conditions, an ethylene glycol yield of 98% could be obtained via the Cu–HMS catalyst using Cu(NH3)4(NO3)2 as the copper precursor. [Copyright &y& Elsevier]

Abstract: Ruthenium (II) supported catalysts containing various amounts of [(η5-MeC5H4)Ru(η3-PPh2CHCH2)(η1-PPh2CHCH2)]+ deposited on aluminated mesoporous silica of HMS type (Si/Al=20 or 40) were synthesized by ion exchange method. The solids were characterized by XRD, 27Al MAS NMR, FTIR and UV–vis spectroscopies. The textural properties were determined from nitrogen adsorption at 77K. Textural analysis showed that increased loading of ruthenium complex onto support with high density of exchange sites (high Al content) eventually leads to overcrowding of active species in pore sections close to the pore mouth and hinders access to sites located deeper within the pore network. All HMS supported catalysts proved active and selective in phenylacetylene semihydrogenation under mild conditions (temperature 40°C and H2 pressure of 1atm), their performance showing a complex pattern depending on the catalyst loading with the active phase and the degree of support alumination. Results indicate that the optimum catalytic performance requires high number of active sites within the catalytically active zone near the pore entrance, simultaneously avoiding blockage of the pore system and loss of the site isolation effect (controlled by Si/Al ratio and active phase content). Best heterogenized catalysts are more active than unsupported ruthenium complex in the homogeneous system. The supported catalysts are stable under reaction conditions and can be easily recovered and reused, without any loss of catalytic activity and selectivity. [Copyright &y& Elsevier]

This study is to load the sing-atom Pd on Cu/ZrO 2 with ion exchange method, and the role of Pd in Cu/ZrO 2 for CO 2 hydrogenation to methanol is investigated. The exchange of Pd with Cu/ZrO 2 increase the methanol production rate from 223 μmol g−1 h−1 to 512 μmol g−1 h−1 at relatively mild conditions (1.5 Mpa, 260 °C). This exchange increases the splitting H adsorptions on Cu species, and strengthen interactions between Cu species and oxygen vacancies at the interface, thus promoting the formations of Cuδ+ species, which is critical to the formation of methanol. This study provides a promising alternative for the understandings the role of exchanged Pd in the Pd-Cu/ZrO 2 catalysts for CO 2 hydrogenation to methanol. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: The cationic ruthenium(II) complex [(η5-MeC5H4)Ru(η3-PPh2CHCH2)(η1-PPh2CHCH2)]+ (1) containing the hemilabile phosphaallyl ligand in two different coordination modes has been immobilized inside the pores of aluminated hexagonal mesoporous silica HMS(Si/Al=40) by direct ion exchange method. This material was characterized by X-ray diffraction, thermogravimetric analysis, FTIR, solid state NMR (29Si, 27Al), UV–Vis, and X-ray photoelectron spectroscopies. The textural properties were determined from nitrogen adsorption at 77K. (1)/HMS(Si/Al=40) was shown to be active and selective in the catalytic hydrogenation of phenylacetylene. [Copyright &y& Elsevier]

Abstract: The paper presents results of the study for obtaining perrhenic acid from aqueous ammonium perrhenate solutions by ion exchange. Two ways of perrhenic acid synthesis have been examined: sorption of perrhenate anion on selected anion exchange resins (followed by elution of the sorbed rhenium as HReO4), and sorption of ammonium ion on selected cation exchange resins. The method of ammonium ion sorption on cation exchange resins has proved to be more effective. Using C 160 (H) cation exchange resin, perrhenic acid containing >300 g/L of Re (after performing concentration in vacuum evaporator) has been obtained, with impurities concentration at the level of: <1.0 mg/L NH4, ≤0.05 mg/L sodium, ≤0.20 mg/L potassium, ≤0.10 mg/L magnesium and ≤0.20 mg/L calcium. [Copyright &y& Elsevier]

A comparison of the distribution coefficients (Kd) of tellurium and iodine-131 (131I) between hydrochloric acid of various concentrations (without and in presence of 0.1 M thiourea) and the cation exchange resin (Dowex50WX8) was studied. The Kd of tellurium and 131I at different concentrations of thiourea in 0.1 M HCl on the Dowex50WX8 was also studied. The results clarified that the maximum uptake of tellurium was 98% on the Dowex50WX8, while the uptakes of 131I and thiourea are 1.96% and 70%, respectively. To purify 131I from thiourea (30%), which is not retained on Dowex50WX8, the remaining solution was shaken with different types of anion exchangers (Dowex21 K, Dowex1X8, and Dowex1X2) within 60 min. The most suitable anion exchanger, which gave the maximum uptake of 131I (80%) was Dowex21 K. Finally, 131I was re-extracted from Dowex21 K into 5 mM TBAB with a separation yield of 98%. Quality control on the separated product of tetra-butyl ammonium iodide (131I) was carried out. [Copyright &y& Elsevier]

Anionic charge compensation creates conditions for realizing high capacity and energy density of Li-ion batteries cathode materials. However, the issues of voltage hysteresis, capacity attenuation, and structure transformation caused by the labile anionic redox are still difficult to solve fundamentally. The superstructure formed by a Li-Mn ordered arrangement is the intrinsic reason to trigger the anionic charge compensation. In this work, manganese-based cathode materials with series of Li-Mn ordered superstructure types have been prepared by an ion exchange method, and superstructure control of the anionic redox behavior has been synthetically investigated. With the dispersion of a LiMn 6 superstructure unit, the aggregation of Li vacancies in Mn slab is gradually inhibited, which eliminates the production of O-O dimers and improves the reversibility of oxygen redox. Therefore, the voltage hysteresis and capacity fading have been significantly improved. Meanwhile, the amount of reactive oxygen species and their capacity contribution is reduced, and the sluggish electrochemical reaction kinetics of anion requires a low current density to boost the high-capacity advantage. This paper provides effective ideas for the design of various superstructures and the rational utilization of anionic redox.

In order to determine the carboxyl groups content in low-rank coals accurately, ion exchange methods was taken to determine the carboxyl groups in Baori brown coal and Pingshuo long flame coal. The effect of ion exchange time, wetting agent (methanol) and pre-acid -extraction was researched. It was concluded that the ion exchange could get completed when ion exchange time was prolonged. The quantity of carboxyl groups detected stay constant when ion exchange time was more than 15 hours. The effect of wetting agent was obvious when ion exchange time was short. While, as the ion exchange time was prolonged, its effect got less obvious. The error caused by inorganic substance could be eliminated by pre-extracting with acid, which made the results more accurate. [ABSTRACT FROM AUTHOR]

Transition metal sulfide/graphene-based composites show broad prospects as electrode materials for supercapacitors. To explore the energy storage mechanism of composites, and clarify the synergistic effect between transition metal sulfide and graphene, a series of composites have been synthesized by adjusting the addition of graphene oxide during the preparation of the composites. The results show that the addition of graphene can effectively inhibit the agglomeration of nickel-cobalt sulfide particles. Cyclic voltammetry revealed that the proportion of surface-controlled capacitance increases with the increase of graphene (from 64.04% to 89.01%). Graphene can significantly improve the capacitance and stability of composites, while exceed graphene degrades the properties of the composites. An asymmetric supercapacitor assembled with NC/rGO25S (adding 25 mg graphene oxide during material synthesis) and activated carbon (AC) provides high specific capacitance (199.3 F g −1 at 2 A g −1) and excellent cycle stability (maintaining 90.4% after 10 000 cycles at 10 A g −1). All in all, the mechanism exploration and performance optimization of NiCo 2 S 4 /rGO in this work are of great significance for the further development of nickel-cobalt sulfide/rGO materials. • Confined growth of NiCo 2 S 4 is achieved by adding appropriate amount of graphene during the synthesis of composites. • Revealing the synergies effects and separately capacitance contributions between nickle-cobalt sulfides and rGO. • Exploring the evolution of phase and morphology of the composite during material synthesis. • The nano-NiCo 2 S 4 /rGO with highly optimized performance is achieved and demonstrated in asymmetric supercapacitor. [ABSTRACT FROM AUTHOR]

The present study examined the hydrogeochemical profile of higher fluoride (F─) in groundwater of mixed industrial and mining areas of Dargai, northern Pakistan. Groundwater samples (n = 75) were collected from three hydrogeochemical environments. The mean concentrations of pH, EC, TDS, Depth and Temperature were (7.6, 1081 μS/cm, 590 mg/L, 75 m, 28.03 °C), for chemical ions viz. NO 3 , PO 4 , SO 4 , Cl, HCO 3 , Na, K, Ca and Mg were (18.5, 2.7, 161, 107, 330, 150, 9.76, 33, 52) mg/L respectively. Whereas, the mean concentration of F─ was 2.0 mg/L. Therefore, 51% groundwater samples exceeded the WHO guideline of F─ 1.5 mg/L. Additionally, we measured the mean F─ concentration in rocks, coal and wastewater, which were (670, 98) mg/Kg and 2.3 mg/L respectively. The principal component analysis multilinear regression (PCA─MLR) extracted five significant factors which shows natural, mixed and anthropogenic pollution. Thus, fluorite is the primary source of F─ contamination in groundwater. While apatite, biotite and muscovite minerals are the secondary sources which occurs in association with quartzite, granite rocks. Under alkaline conditions, F─ contamination is supported by higher Na+, HCO 3 ─ and lower Ca++ concentrations. The accuracy and reproducibility of the measurement of fluoride was assessed by adopting a standard method of water. The percentage recovery of F─ was 97% and reproducibility was within ±5% error limit. Lastly, a health risk community fluorosis index (CFI) was calculated through Dean's formula which shows unsuitability of groundwater sources conceiving community fluorosis in the entire study area. • Groundwater of Dargai region, Pakistan was analyzed for fluoride concentrations. • 51% of groundwater samples exceeded the WHO guideline value of 1.5 mg/L of F─. • F─ occurrence in water is linked to ion exchange, weathering and mining actions. • PCA-MLR results of groundwater shows 64% contamination was due to geogenic source. • CaHCO 3 (49%), NaHCO 3 and NaCl (51%) are the major water type of the study area. [ABSTRACT FROM AUTHOR]

The separation of 67Ga from zinc and copper target materials using an anion-exchanger (Dowex21K) and 0.1 M citrate buffer at pH 6 is described. The gallium-67 was separated in citrate solution and can be directly used for medical applications. [Copyright &y& Elsevier]

Polyimide film (Kapton) is an important polymer material used for the construction of spacecrafts. The performance of Kapton can be degraded for atomic oxygen erosion in space. Commonly used atomic oxygen protective layers have issues such as poor toughness and poor adhesion with the film. In this paper, Kapton/Al2O3 nanocomposite films were prepared via an ion exchange method, and the optical properties, mechanical properties, and mechanisms for the change in the mass and microstructure, before and after atomic oxygen exposure, were analyzed. The results show that the deposition of the Kapton/Al2O3 surface nanocomposite film prepared via the ion exchange method has no obvious effects on the internal structure and optical transmittance of the Kapton film matrix. The tensile strength and elongation of the prepared film were much higher than those of the pure Kapton film, demonstrating its good flexibility. Scanning electron microscope (SEM) analysis showed that the etching pits had a carpet-like morphology on the composite film surface and were relatively small after atomic oxygen erosion. In contrast with the C–C bond rupture in the oxydianiline (ODA) benzene in Kapton films, the Kapton/Al2O3 nanocomposite film mainly destroyed the C=C bond in the pyromellitic dianhydride (PMDA) benzene ring. On exposure to an atomic oxygen environment for a short period, the Kapton/Al2O3 nanocomposite film exhibited improved atomic oxygen erosion resistance because the Al2O3 layer inhibited atomic oxygen diffusion. With increasing atomic oxygen exposure time, the atomic oxygen diffused into the Kapton matrix via the pores of the Al2O3 layer, causing damage to the substrate. This resulted in a detachment of the surface Al2O3 layer and exposure of the Kapton matrix, and thereby the atomic oxygen resistance was decreased. The applicability of the ion exchange mechanism of trivalent Al element on the surface modification of the polyimide is explored in this study. The behavior of the Kapton/Al2O3 composite film under the atomic oxygen environment of space is investigated, which provides the basis for studying the effects of atomic oxygen on the flexible protective Kapton film. [ABSTRACT FROM AUTHOR]

The west part of Turkey has great potential for geothermal energy resources. The exploitation of this potential in the Denizli-Kizildere geothermal energy region depends on the removal of its high boron content since waste brine is discharged into the nearby River Buyuk Menderes. This river is an important source of agricultural irrigation, so consideration must be given to the amount and quality of the added geothermal waste water. A study is made of boron removal from Kizildere/Turkey geothermal wastewater using ion exchange resin. The use of ion exchange resin for the removal of boron from wastewaters requiresexpensive regeneration steps. A three stage acid regeneration process has been investigated to find the optimal operational conditions for minimizing the regenerant consumption. Boron removal after three stage acid regeneration with 5% H2SO 4 possible since the wastewater of the Kizildere geothermal field has enough buffering capacity to neutralize the released acid from the resin. [ABSTRACT FROM AUTHOR]