Cerium Cations Research Articles

Tetravalent Cerium Cation Imprinted Crosslinked Acrylamide/Alginic Acid Copolymer Network: A Sorption and Ce(IV) Ion-Selectivity Study from Aqueous Solutions

A novel tetravalent cerium cation-imprinted crosslinked polymer network (Ce(IV)-CICPN) based on polyacrylamide was synthesized by metal-ion-imprinting strategy in an aqueous medium with N,N-methylene-bis-acrylamide (NNMBA) as crosslinker. The synthesized CPN is characterized by UV-Vis spectroscopy, FTIR spectroscopy, PXRD analysis, SEM studies, EDX and thermogravimetric analysis. The adsorption performance was studied using adsorption isotherms and kinetics. The Ce(IV)-CICPN was optimized for maximum Ce(IV) ion sorption using the batch equilibration method, and its performance has been compared with that of a non-imprinted crosslinked polymer network (non-imprinted CPN). It was found that it possesses a maximum adsorption capacity of 70.3 mg/g. The surface area of both Ce(IV)-CICPN and non-imprinted CPNs were determined by BET surface area analysis and found to be 2.103 m2 g–1 and 0.62 m2 g–1, respectively. Polymer efficiency as a selective sorbent for Ce(IV) ion was estimated through examining its selectivity relative to Zn(II), Mg(II), Cr(IV) and V(V).

Catalytic oxidation of vinyl chloride over Co–Ce composite oxides derived from ZIF-67 template: Effect of cerium incorporation

Transition metal oxides are regarded as an economical and efficient catalytic alternate for catalytic oxidation of volatile organic compounds (VOCs) emissions. The morphological decoration and the incorporation of extrinsic metals were demonstrated to be effective strategies for achieving noticeable catalytic improvement. In this work, a novel Co–Ce composite oxides catalyst was obtained by the pyrolysis of ZIF-67 template with the impregnation of certain cerium cations (denoted as ZIF-CoCe). Compared with the reference Co–Ce composite oxides by the sol-gel (denoted as SG-CoCe) and physical mixing (denoted as MIX-CoCe) methods, ZIF-CoCe delivers significantly higher catalytic activity for vinyl chloride oxidation, which are demonstrated to be closely related with its superior redox capacity, more abundance of surface active Co3+ sites and adsorbed active oxygen species from oxygen vacancies. In addition, the unique cage-like morphological feature of the Co-based catalysts derived from ZIF-67 template plays a crucial function in kinetically facilitating the mass transfer of catalytic reaction and promoting the catalytic VC oxidation activity. With regard to in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTs) analysis, enol and carboxylic acid species are identified to be the key organic intermediates during catalytic vinyl chloride oxidation.

Synergistic anticorrosion effect of Brassica Hirta phytoconstituents and cerium ions on mild steel in saline media: Surface and electrochemical evaluations

Among all the issues that industries will encounter, corrosion is the most concerning. Up to now, corrosion left notable problems in industrial processes and that is why the researchers proposed various methods for limiting its drawbacks. The present work aim is to analyze the impact of Brassica Hirta extract, which is popularly called Mustard, on steel corrosion mitigation and its synergistic effect in mixture with cerium (Ce) cations by using electrochemical and morphological methods. One of the advantages of this inhibitor is its low cost, which is caused by the two factors of the water-based extraction process and the initial cost of the plant purchasing. Moreover, due to the mentioned extraction process, the ME can be considered an eco-friendly inhibitor. In addition, the ME is accessible in most parts of the world. The film composition screening was done by EDS, mapping, and GIXRD techniques, and by FE-SEM and AFM technics, both surface morphology investigation and topographical explorations were done.The findings confirm that the Mustard extract (ME) inhibition impact was boosted in the presence of Ce cations and the mixture performance was optimized at 200:600 ppm ME:Ce mixture concentration. The electrochemical impedance spectroscopy (EIS) and polarization records illustrated that the mixture could retard the corrosion by 94% and 92% of steel corrosion after 48 h of steel immersion, respectively. Also, the synergistic index value of 200:600 ppm ME:Ce ascended steadily from 2.50 until reaching 7.44. The morphology of the film deposited on the surface and its microstructure including ME:Ce complex was demonstrated. The GIXRD analysis outcomes besides EDS and mapping detections confirmed that the protective layer formed includes ME phytochemicals and Ce oxide/hydroxides.

Biomedical applications of ion-doped bioactive glass: a review

Bioactive glasses (BG) have been used in biomedical (dental applications or bone graft replacement for bone healing) and technological applications, and researchers have focused on the use of BGs in wound therapeutic and soft tissue. Researchers are concentrating their efforts on the creation of novel treatments for microbial infections due to the worrisome and rapid rise in drug-resistant microbial-related infections. In this review paper, we will discuss the main representatives of antimicrobial efficiency of metallic ion-doped bioactive glasses and their potential applications in the medical field. We will also go over the most important currently used and newly developed methods for surface and bulk modification of metallic ion-doped BG concerning new surgical therapy, which are used to enhance bio integration, pathogen killing effectiveness, decrease or eliminate cancer cells, mechanistic integration, a reduction in material costs, improved in BG bioactivity, angiogenic potential, biocompatibility, osteoconductive, biodegradability and mechanical integration. The integration and regulated release of antibacterial metallic ions like silver, copper, zinc, manganese, cerium, and gallium cations into the BG are one of the most appealing methods for preventing bacterial growth and reproduction. The porosity of BG matrixes (metallic ion-doped BG with micro-, meso-, and macro-porous porosity types), in combination with their low cytotoxicity, high specific surface area, and tunable pore structure, greatly facilitates the formation of hydroxyapatite or hydroxyl carbonate apatite.

Designing Ceria/Alumina for Efficient Trapping of Platinum Single Atoms

Cerium oxide (ceria) has been shown to be very effective at trapping platinum atoms due to formation of stable surface complexes at step edges, where coordinatively unsaturated cerium cations are present. But ceria loses its effectiveness when heated to high temperatures due to loss of surface area and growth in particle size associated with sintering of the oxide. Being a rare earth, and with limited supplies worldwide, it is important to develop methods to improve the effectiveness of ceria as a catalyst support. Here, we explore the performance for trapping Pt atoms when the ceria is supported on a high surface area alumina carrier. This helps create a more sustainable catalyst formulation, especially if we can retain the high dispersion of Pt seen on ceria supports. For this work, we studied the atom trapping efficacy of ceria/alumina samples with increasing ceria content (8–50 wt %) and contrasted the behavior with pure ceria. Electron microscopy reveals that when dispersed on alumina, ceria is present in the form of crystalline nanoparticles and isolated cerium ions. These two forms of ceria differ markedly in their ability to trap Pt atoms. Atomically dispersed cerium is present in the form of Ce3+ cations on alumina; however, this form of ceria is not effective for trapping Pt atoms. Our results show that the atom-trapped Pt resides primarily on crystalline ceria nanoparticles. CO oxidation was used as a probe reaction to evaluate the performance of these PtAT/ceria-alumina catalysts. We conclude that over the range of ceria loadings we investigated, 50% ceria/alumina represents the optimal catalyst support for achieving high surface area and atom trapping efficiency while helping reduce the total ceria content in this catalyst system.

Cerium-doped tannic acid-reduced graphene oxide nanoplatform/epoxy nanocomposite coatings with enhanced mechanical and Bi-functional corrosion protection properties

There has been an explosion of interest toward incorporating graphene-based nanomaterials for corrosion protective coatings. In this study, tannic acid (TA) was employed as a green reducing agent of graphene oxide (TA-rGO) to provide promising nanoplatforms with good dispersion in an epoxy matrix for enhanced mechanical and anti-corrosion properties. In addition, these nanoplatforms were doped with cerium cations (Ce@TA-rGO) to improve active corrosion protection. The designed nanosheets were characterized by several techniques, including FT-IR, XRD, UV–visible, FE-SEM/EDS, TEM, TGA, and XPS. TA improved the thermal properties of graphene oxide significantly with only 40% weight loss up to 800 °C. Furthermore, EIS studies revealed that introducing Ce@TA-rGO nanoplatforms into epoxy coating led to ∼71.5% improvement in active corrosion protection in a saline solution due to the smart release of Ce3+. In addition, Ce@TA-rGO nanoplatforms presented excellent barrier properties without electrolyte diffusion after 10 weeks of immersion. In terms of mechanical properties, Ce@TA-rGO-EP and TA-rGO-EP nanocomposites showed higher cross-linking densities and tensile strengths than unfilled epoxy, originating from improvement in the level of dispersion and interaction of nanoplatforms with the polymer.

Structural, optical and electrical study of new polycrystalline Bi1.5-xCexSb1.5CuO7 solid solution fractions with pyrochlore-type structure

This study is a contribution to the development of novel materials based on transition multi metal oxides, which can be applied as photocatalysts or solid electrolytes in solid fuel cells. A new pyrochlore-like solid solution fractions with general chemical formula Bi1.5−xCexSb1.5CuO7 was synthetized and characterized using solid-state reaction and characterized by X-ray powder diffraction (XRPD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), electrical resistivity measurements and solid-state ultraviolet–visible spectroscopy (UV–Vis). The XRDP analysis revealed a high purity pyrochlore-like structure of the solid solution fractions, this being primary with cerium saturation between x=0.2. and x=0.4. A significant decrease of the refined cubic cell parameter was observed, in accordance with the size difference between bismuth and cerium cations. Also, a drastic drop off in electrical resistivity was observed at x=0.4. Besides, the core level X-ray photoelectron spectroscopy technique clearly detected the presence of all elements involved in the composition of these materials, and proved the simultaneous trivalent and tetravalent oxidation states of incorporated cerium. Furthermore, secondary and back-scattered electrons scanning electron microscopy analysis allowed the monitoring of the grain size as well as the phase inhomogeneity of the solid solution fractions. Finally, it was thus found that the optical band gap energy of the solid solution fractions was about 1.8 ​eV.

Novel Ce-modified cobalt catalysts supported over α-Al2O3 open cell foams for lean methane oxidation

A series of CeO2-modified Co3O4 catalysts supported over α-Al2O3 foams was prepared by solution combustion synthesis and examined for the lean methane oxidation. Two different fuels were used namely, urea and glycine, with varying fuel/oxidiser (Φ) ratio. The catalysts were characterised by SEM-EDX, STEM-HAADF coupled to EDX mapping, ICP-AES, WDXRF, N2 physisorption, XRD, HRTEM, Raman spectroscopy, XPS, H2-TPR and CH4-TPRe, and their activity in the abatement of methane was analysed under realistic conditions. The use of glycine produced catalysts with significantly better morphological and structural properties. Likewise, a favoured insertion of cerium cations into the Co3O4 spinel lattice was observed, which caused a significant distortion of the spinel structure, thereby leading to a higher amount of mobile oxygen species capable of oxidising methane. These beneficial structural alterations were more pronounced with higher Φ ratios.

A Novelty Analytical Approach to Determine Oxidation States in Complex Refractory Oxides Containing Iron, Uranium, Cerium and other Mixed Valence Cations

Titrimetry technique has been used for the first time to determine the oxidation state in complex refractory oxides containing iron, uranium, cerium, and other mixed valence cations. In particular, sodium molybdate (3Na2O-4MoO3), used as an oxidative solvent for metal oxides. Cerium (IV) sulfate solution which prepared with sulfuric acid was used as a titrant. The excess Ce (IV) is back titrated with Fe (II) standard solution with indicator ferroin. The mechanism and the results have been interpreted.

Ceria particles synthesized via combustion method to inspire active protection for epoxy coating on mild steel

This research aims to study the effect of fuel type in the combustion synthesis of CeO2 particles on their corrosion inhibitive activity in an epoxy coating. For this purpose, four different types of CeO2 particles were prepared using urea, glycine, glucose, and citric acid as the fuel source. The release of Ce4+ cations from CeO2 particles in 3.5% NaCl solution was assessed by inductively coupled plasma (ICP) analysis. The results indicated that CeO2 particles synthesized by urea (URE) released about ten times more cerium cations compared to the CeO2 particles synthesized by other fuels. The corrosion behavior of bare steel in saline solution in the presence and absence of released Ce4+ cations and the corrosion inhibitive performance of scratched coatings containing CeO2 particles were assessed by electrochemical techniques. Results showed considerable improvement in the impedance values in both solution and coating phases, specifically in the presence of URE. Besides, field emission scanning electron microscopy (FESEM) and energy dispersive spectroscopy (EDS) were utilized to characterize the bare steel surface and the scratched area of coated samples after exposure to the test solutions. Surface analysis results showed that the least corrosion products were formed on the URE sample, confirming its highest inhibitive activity. The adhesion and protective behavior of epoxy coatings were also determined by pull-off and salt spray tests, respectively. Overall, the results revealed that the CeO2 particles synthesized by urea showed the highest anti-corrosion properties due to their highest capability to release the Ce4+ cations.

Ceramic Restorations Based on Zirconium Dioxide for Orthopedic Dentistry

Currently, ceramics based on solid solutions of zirconium dioxide tetragonal structure are common biomedical materials. In commercially common ceramics of orthopedic dentistry based on zirconium dioxide, the stabilization of the tetragonal shape is achieved by the introduction of yttrium or cerium cations. As a result of this scientific work, a ceramic material based on nanopowders of a system of zirconium dioxide and ytterbium oxide with high strength parameters has been developed. The results of the conducted research allow us to recommend the new Yb–TZP ceramics as an alternative to Y–TZP ceramic materials for restorations in orthopedic dentistry.

Heterometallic CeIV/ VV Oxo Clusters with Adjustable Catalytic Reactivities.

Heterometallic CeIV/M oxo clusters are underexplored yet and can benefit from synergistic properties from combining cerium and other metal cations to produce efficient redox catalysts. Herein, we designed and synthesized a series of new Ce12V6 oxo clusters with different capping ligands: Ce12V6-SO4, Ce12V6-OTs (OTs: toluenesulfonic acid), and Ce12V6-NBSA (NBSA: nitrobenzenesulfonic acid). Single crystal X-ray diffraction (SCXRD) for all three structures reveals a Ce12V6 cubane core formulated [Ce12(VO)6O24]18+ with cerium on the edges of the cube, vanadyl capping the faces, and sulfate on the corners. While infrared spectroscopy (IR), ultraviolet-visible spectroscopy (UV-vis), electrospray ionization mass spectrometry (ESI-MS), and proton nuclear magnetic resonance (1H NMR) proved the successful coordination of the organic ligands to the Ce12V6 core, liquid phase 51V NMR and small-angle X-ray scattering (SAXS) confirmed the integrity of the clusters in the organic solutions. Furthermore, functionalization of the Ce12V6 core with organic ligands both provides increased solubility in term of homogeneous application and introduces porosity to the assemblies of Ce12V6-OTs and Ce12V6-NBSA in term of heterogeneous application, thus allowing more catalytic sites to be accessible and improving reactivity as compared to the nonporous and less soluble Ce12V6-SO4. Meanwhile, the coordinated ligands also influenced the electronic environment of the catalytic sites, in turn affecting the reactivity of the cluster, which we probed by the selective oxidation of 2-chloroethyl ethyl sulfide (CEES). This work provides a strategy to make full use of the catalytic sites within a class of inorganic sulfate capped clusters via organic ligand introduction.

Graphene loaded with corrosion inhibitor cerium (Ⅲ) cation for enhancing corrosion resistance of waterborne epoxy coating: Physical barrier and self-healing

Tannic acid (TA) was self-assembled with graphene (Gr) via π-π interaction. Then green corrosion inhibitor cerium (Ⅲ) cation (Ce3+) was loaded on graphene sheets through a reversible complexation with tannic acid which is depending on pH value, enabling the release of Ce3+ in an acid environment. Characterization methods including fourier transform infrared spectroscopy (FT-IR), raman spectroscopy, transmission electron microscope (TEM), x-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) mapping verified the successful preparation of Gr-TA and Gr-TA-Ce3+ hybrid materials. Electrochemical impedance spectroscopy (EIS) results of bare steel in the Gr-TA-Ce3+ extract showed the self-healing of Gr-TA-Ce3+ nanofillers which increased the impedance modulus at 0.01 Hz by one order of magnitude compared with bare steel. Waterborne epoxy coating doped with Gr-TA-Ce3+ material exhibited significant barrier performance originated from shielding property of graphene nanosheets against corrosive mediums and efficient self-healing capacity derived from the protective film formed by cerium cations. Electrochemical impedance spectroscopy results manifested that coating doped with Gr-TA-Ce3+ material maintained impedance modulus at 0.01 Hz of ~2.90 × 107 Ω.cm2 after immersion in 3.5 wt% sodium chloride solution for 60 days, two orders of magnitude higher than neat epoxy coating.

Cerium containing pH-responsive microcapsule for smart coating application: Characterization and corrosion study

In the following paper first, novel pH-sensitive melamine-formaldehyde microcapsules containing ethylene glycol with three concentrations of cerium nitrate were synthesized. Then, three different quantities of the microcapsules were introduced to the epoxy coatings and applied on the AA2024-T3 substrate to meet the increasing demands for self-healing coatings. The characteristics of microcapsules were studied by scanning electron microscope (SEM), transmission electron microscope (TEM), Fourier transform infrared (FTIR), and dynamic light scattering (DLS). The UV–Vis spectroscopy was accomplished to the appraise pH-triggered release of the microcapsules. The salt spray test along with electrochemical impedance spectroscopy (EIS) was conducted for studying the anti-corrosion and self-healing proficiency of microcapsule-based coatings. The UV–Vis spectroscopy outcomes showed that the synthesized microcapsules are responsive to alkaline pH and the release rate of microcapsules in the basic medium rises with increasing the pH values. Moreover, the EIS and salt spray results indicated that incorporation of 10 wt% of the microcapsules into the epoxy coating not only improved the anti-corrosion strength of the aluminum substrate compared to neat epoxy coating remarkably but also, provided active corrosion protection of the substrate through the self-healing action of cerium ions. Also, the attendance of cerium cations in the scratch surface was confirmed by field emission scanning electron microscopy (FE-SEM) and energy-dispersive X-ray (EDX) map.

Impact of PEM Durability and Performance on Chemically Immobilized Polyoxometalate Additive to VDF Blended 3M PFSA Ionomer

Durability of the proton exchange membranes fuel cells (PEMFC) has been the major challenge for fuel cell vehicle applications. Despite the high proton conductivity and power density, hydroxide and radical formation during fuel cell operation has led to the durability issue for the PEMFC. Cerium and manganese cations and oxides have been adopted to be used as radical scavenger. However, mobilization of the cerium and manganese cations and oxides have been reported. The migration resulted in forming a cluster of metal oxides that caused loss of radical scavenging function or metal oxide itself leaving the membrane system. In contrast to implementing metal oxide additives, chemically bound polyoxometalate can be chemically stable and immobilized. Our group has previously showed that polyoxometalate bound fluroelastomers not only can catalyze radical scavenging and enhance durability but also achieve higher proton conductivity due to polyoxometalate being proton conductive itself.This work focuses on analyzing the impact of polyoxometalate additive to VDF blended perflourinated sulfonic acid (PFSA) ionomer. Proton conductivity of the membrane was measured using electrochemical impedance spectroscopy (EIS) under different temperature and relative humidity conditions. Activation Energy of the chemically immobilized polyoxometalate membrane was analyzed. Both micron- and nano-scale morphology was analyzed using electron scanning microscope (ESEM), high-resolution transmission electron microscope (HRTEM), and small angle x-ray scattering (SAXS). Chemical and thermal characterization was studied through FTIR, TGA, and DSC. Correlation between water uptake and membrane properties was explored using DVS. Lastly, lab-scale fuel cell durability test under AST condition was conducted to investigate the performance and durability enhancement.

Ce-substituted Mg-Al layered double hydroxides to prolong the corrosion protection lifetime of aluminium alloys

Layered double hydroxides (LDH) have emerged as an alternative to chromates for corrosion protection by exploiting anion-exchange phenomena: the LDH releases corrosion inhibitor anions and captures the corrosive agent anions, extending the metal surface lifetime. In this work, the main aim was to promote continuation of corrosion protection after the end of the process of anion-exchange. For this purpose, cerium cations, which possess corrosion protection capability, were incorporated in the LDH structure via partial substitution of aluminium cations. The changes occurring to the LDH in solution after exposure for an extended period of 30 days to UV radiation, were evaluated. The study was performed using Mg3Al1-xCex LDH intercalated with nitrate, where x was 7.5 mol%, Ce3+ release from the hydroxide layers being promoted by UV-radiation-induced LDH degradation. The release of Ce3+ from the hydroxide layers was quantified by UV-visible spectroscopy. The continued corrosion protection of aluminium alloy 2024 immersed in a solution with and without the presence of degraded LDH was examined by electrochemical impedance spectroscopy and surface analysis.

Amino-Functionalized MXene Nanosheets Doped with Ce(III) as Potent Nanocontainers toward Self-Healing Epoxy Nanocomposite Coating for Corrosion Protection of Mild Steel.

MXene sheets, as new 2D nanomaterials, have been used in many advanced applications due to their superior thin-layered architecture, as well as their capability to be employed as novel nanocontainers for advanced applications. In this research, intercalated Ti3C2 MXene sheets were synthesized through an etching method, and then they were modified with 3-aminopropyltriethoxysilane (APTES). Cerium cations (Ce3+) as an eco-friendly corrosion inhibitor were encapsulated within Ti3C2 MXene sheets to fabricate novel self-healing epoxy nanocomposite coatings. The corrosion protection performance (CPP) of Ce3+-doped Ti3C2 MXene nanosheets (Ti3C2 MXene-Ce3+) in a 3.5 wt % sodium chloride (NaCl) solution was studied on bare mild steel substrates using electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization measurements. The self-healing CPP of epoxy coatings loaded with 1 wt % undoped and doped Ti3C2 MXene was evaluated using EIS, salt spray, and field emission scanning electron microscopy (FE-SEM) techniques. The introduction of Ti3C2 MXene-Ce3+ into the corrosive solution and artificially scribed epoxy coating enhanced the total impedance from 717 to 6596 Ω cm2 and 8876 to 32092 Ω cm2, respectively, after 24 h of immersion compared to the control samples.

Electrochemical Behavior of Ce(IV)/Ce(III) Couple in N,N‐Di(2‐ethylhexyl)‐n‐butanamide (DEHBA), N,N‐Di(2‐ethylhexyl)‐iso‐butanamide (DEHiBA), and N,N‐Di(2‐ethylhexyl)‐3,3‐dimethyl Butanamide (DEHDMBA)

AbstractIn this work we report on the electrochemical behavior of Ce(IV)/Ce(III) redox couple in pure N,N‐dialkyl amides (N,N‐DA), namely N,N‐di(2‐ethylhexyl)‐n‐butanamide (DEHBA), N,N‐di(2‐ethylhexyl)‐iso‐butanamide (DEHiBA), and N,N‐di(2‐ethylhexyl)‐3,3‐dimethyl butanamide (DEHDMBA) equilibrated with nitric aqueous solutions as an entry to the direct electrochemical characterization of plutonium in these extractants. Ce(IV)/Ce(III) redox process was used as a model. Its potential (E1/2≅1.02 V/SCE) is not affected by the temperature and the nature of the N,N‐DA and this clearly indicates that the functionalities of these extractants produce the same relative effect on both +IV and +III oxidation states of the cerium cation. Linear variations of the current intensity of the reduction peak of Ce(IV) with the concentration of Ce(IV)/N,N‐DAs/HNO3(5 M) solutions were obtained from cyclic voltammograms recorded at 25 °C and 40 °C. Due to the poor definition of the voltammograms in DEHiBA and DEHDMBA, such characterization allows only the evaluation of the performances of the chemical extraction of Ce(IV) from aqueous nitric acid solution by the undiluted DEHBA. To our knowledge, the electrochemical behavior of Ce(IV)/Ce(III) in N,N‐DAs was not previously studied and our findings will for sure open the door for further investigations in this field.

Effect of Hyamine-1622 Cationic Surfactant on Pertraction of Cerium (IV) Cations Through Emulsion Liquid Membranes

The present study aims to shed light directly towards the extraction of (IV) cerium ions using "liquid surfactant membrane" technology, "LSM" developed in the presence of synergistic cationic and nonionic materials. The effect of various factors such as Ce (IV) transport, synergistic surfactants, curing ratio, stir speed, temperature, and mixing time between the carrier and the cerium ion on the extraction rate was studied by LSM taking into account surfactant agents. The positive effect of benzethonium chloride "Hy-1622" on the extraction of cerium ion was demonstrated by LSMs technique. Experiments confirmed the efficiency of Hy-1622 chloride synergistically with Span 80/85 to extract cerium ions with LSMs technology for emulsions in the oil phase is critical as it determines the stability, viscosity and mass transfer resistance of the resulting emulsion. Besides, Hy-1622 chloride was found as a new cationic surfactant that appeared in FTIR characterization and surfactant was found to speed up the permeability process and accelerate the extraction rate due to electrostatic interaction with the carrier.

New cation deficient scheelites (Sr,Ce)nWO4 (n

New cation deficient tetragonal scheelites, (Sr,Ce)nWO4 (n ​< ​1) were synthesized using the Ethylene-DiamineTetraacetic Acid-citrate method. The chemical compositions and homogeneity of the powders were determined by Energy Dispersive Spectroscopy. Whatever the cerium amount, the cation deficient scheelites exhibit (3 ​+ ​2)D tetragonal incommensurate modulations, which evolve with cerium and structural cations vacancies amount. The optical absorption onset varies from 400 ​nm to 450 ​nm with the increase of the Ce amount. The optical bandgap of the strontium cerium tungstates cation deficient scheelites (3.18–3.42eV) is much lower than the one of pure scheelite SrWO4 (4.51eV) and near the one of Ce2W3O12 (3.14 ​eV).