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Layered Double Hydroxides (LDHs) are inorganic compounds of relevance to various domains, where their surface reactivity and/or intercalation capacities can be advantageously exploited for the retention/release of ionic and molecular species. In this study, we have explored specifically the applicability in the field of bone regeneration of one LDH composition, denoted “MgFeCO3”, of which components are already present in vivo, so as to convey a biocompatibility character. The propensity to be used as a bone substitute depends, however, on their ability to allow the fabrication of 3D constructs able to be implanted in bone sites. In this work, we display two appealing approaches for the processing of MgFeCO3 LDH particles to prepare (i) porous 3D scaffolds by freeze-casting, involving an alginate biopolymeric matrix, and (ii) pure MgFeCO3 LDH monoliths by Spark Plasma Sintering (SPS) at low temperature. We then explored the capacity of such LDH particles or monoliths to interact quantitatively with molecular moieties/drugs in view of their local release. The experimental data were complemented by computational chemistry calculations (Monte Carlo) to examine in more detail the mineral–organic interactions at play. Finally, preliminary in vitro tests on osteoblastic MG63 cells confirmed the high biocompatible character of this LDH composition. It was confirmed that (i) thermodynamically metastable LDH could be successfully consolidated into a monolith through SPS, (ii) the LDH particles could be incorporated into a polymer matrix through freeze casting, and (iii) the LDH in the consolidated monolith could incorporate and release drug molecules in a controlled manner. In other words, our results indicate that the MgFeCO3 LDH (pyroaurite structure) may be seen as a new promising compound for the setup of bone substitute biomaterials with tailorable drug delivery capacity, including for personalized medicine.

This review focuses on recent advances in the post-synthetic modification of nano-sized Prussian blue and its analogues and compares them with the current strategies used in metal–organic frameworks to give future outlooks in this field.

Erbium(iii) complexes based on halogenated ligands.

Antibiotics are found in natural waters, raising concern about their human and environmental toxicity and the wide occurrence of antibiotic resistant bacteria. The antibiotic resistance crisis is attributed to the overuse and misuse of these medications. Particularly, sulfamethazine (SMT), an antibiotic commonly used in pigs and cattle for the treatment of bacterial diseases, has been detected in the natural environment (soil and water). Among all the technologies developed to combat the deteriorating water quality and control antimicrobial resistance, heterogeneous photocatalysis should be highlighted for the degradation of refractory organic compounds. Here, we described the SMT adsorption and photodegradation capacity of a highly porous and robust zirconium-based MOF UiO-66 under realistic conditions, and its potential recyclability. Further, its SMT removal capacity was improved by functionalizing the MOF porosity (28.5% of SMT adsorption in 24 h for nanoUiO-66-NH2), and nanosizing the MOF (100% SMT photodegradation in only 4 h for nanoUiO-66). Finally, the safety of the formed by-product during SMT photodegradation was confirmed, reinforcing the potential of the application of UiO-66 in water remediation.

International audience; We demonstrate here that Mn 2+-doped Prussian blue nanoparticles of ca. 55 nm loaded with doxorubicin may be used as efficient therapeutic agents for combined photothermal and chemo-therapy of cancer cells with a synergic effect under two photon irradiation. Photothermal therapy (PTT) is a promising strategy for the therapeutic treatment of tumours, which consists in "burning" cancer cells by laser irradiation at low energy wavelengths in the presence of an NIR photo-adsorbing agent. 1,2 In comparison to conventional cancer treatments, it offers several advantages, such as high specicity, deep penetration, lower tumour recurrence, minimal invasiveness and low toxicity to normal tissues. 3,4 Due to the fact that the treatment efficiency highly depends on the outstanding capacity of the PTT agent to convert light into heat, numerous materials have recently been reported , such as organic dyes 5,6 or various inorganic nano-objects, including metallic nanostructures (Au nanorods or nanoshells, Ag, Pd), carbon based materials (nanotubes, spheres, graphene oxide), transition metal dichalcogenide nanoparticles, metal oxide nano-objects or up-conversion nanocrystals. 7-16 Among these, Prussian blue (PB) nano-objects have been developed as interesting PTT agents since they benet from many advantages, such as: (i) a controlled size ranging from a few to hundreds of nanometers, (ii) easy surface functionali-zation, (iii) excellent absorption properties in the NIR spectral domain due to an Fe 2+ to Fe 3+ intervalence charge transfer band ranging from 650 to 900 nm, (iv) high stability under irradiation , and (v) the fact that bulk PB is validated by the FDA under the brand name Radiogardase® as an antidote for human beings exposed to radioactive Cs +. 17 It has been shown in vitro that PB nanoparticles upon single photon excitation (SPE) (at 808 nm) can convert the laser irradiation into thermal energy contributing to an important temperature increase. 18,19 Their efficiency depends on the nanoparticles' concentration, their chemical composition, the laser power, the mode of irradiation and the irradiation time. Moreover, it has been demonstrated that nano-sized PB presents a higher efficiency in comparison with Au nanorods and a better photothermal stability than organic dyes used as conventional photothermal agents. 19,20 PTT effect of PB nanoparticles has also been demonstrated in vivo through their intra-tumoral injection that causes signicant tumour necrosis 24 h aer NIR irradiation in comparison with non-treated mice. 18 Nevertheless, the complete eradication of cancer cells using solely PTT treatment is rather difficult due to the suboptimal laser energy in deep tissues related to light scattering and absorption effects, a limited light penetration and the insufficient tumour target specicity of PTT agents. Some of these drawbacks may be circumvented using two photon excitation (TPE), which permits to increase the penetration depth and laser focalization allowing selective and efficient destruction of the targeted cancer cells with less damage to healthy tissues. 21-23 In this line of thought, we reported recently Mn 2+-doped PB nanoparticles of ca. 70 nm as efficient multifunctional PTT agents permitting to eradicate 97% of cancer cells 24 h aer irradiation under TPE during 10 min, which may also be followed by Magnetic Resonance Imaging (MRI). 24 However, the comparison between the efficiency of the single and two-photon excitations on the same nano-objects has never been investigated.

We report the synthesis, structures, and magnetic investigations of two new octahedral dysprosium complexes, based on the original N-heterocyclic carbene (NHC) tridentate bis(phenoxide) ligand, of the respective formulas

We report the synthesis, structures, magnetic and luminescence properties of a series of three-blade propeller homoleptic lanthanide complexes [LnL3](ClO4)3·H2O·2MeCN (Ln = Eu (1), Tb (2), Dy (3), Er (4), Yb (5), Gd (6); L = 2,6-bis(1-methyl-imidazol-2-yl)pyridine). The Eu, Tb, and Dy analogues exhibit the characteristic lanthanide-based luminescence. Remarkably, the mixed Eu/Tb complex with a metal ratio of 1 : 10 can be used as a ratiometric thermometer in the solid-state between 130 and 220 K with the maximum value of Sr = 6.6% K−1 within the range of 150-170 K. Theoretical calculations allow not only modelling of the luminescence properties of pure complexes but also rationalization of the performances of the mixed Eu/Tb thermometers published

We investigated a series of Mn

International audience; We investigated a series of Mn(2+)-Prussian blue (PB) nanoparticles Na(z)Mn(x)Fe(1-x)[Fe(CN)(6)](1-y□y)·nH(2)O of similar size, surface state and cubic morphology with various amounts of Mn(2+) synthesized through a one step self-assembly reaction. We demonstrated by a combined experimental-theoretical approach that during the synthesis, Mn(2+) substituted Fe(3+) up to a Mn/Na-Mn-Fe ratio of 32 at% in the PB structure, while for higher amounts, the Mn(2)[Fe(CN)(6)] analogue is obtained. For comparison, the post-synthetic insertion of Mn2+ in PB nanoparticles was also investigated and completed with Monte-Carlo simulations to probe the plausible adsorption sites. The photothermal conversion efficiency (η) of selected samples was determined and showed a clear dependence on the Mn(2+)amount with a maximum efficiency for a Mn/Na-Mn-Fe ratio of 10 at% associated with a dependence on the nanoparticle concentration. Evaluation of the in vitro photothermal properties of these nanoparticles performed on triple negative human breast adenocarcinoma (MDA-MB-231) cells by using continuous and pulsed laser irradiation confirm their excellent PTT efficiency permitting low dose use.

International audience; Recently potassium-ion batteries have been proposed as a promising next generation battery technology owing to cost effectiveness and a wide range of electrode materials as well as electrolytes available. Potassium bis(fluorosulfonyl)imide (KFSI) in monoglyme (DME) is one potential electrolyte, wherein the K+ solvation heavily depends on the salt concentration and strongly affects the electrochemistry. Pure K+ intercalation occurs for highly concentrated electrolytes (HCEs), while co-intercalation is dominant for less concentrated electrolytes. The mechanisms are easily distinguished by their galvanostatic curves as well as by operando XRD. Here Raman spectroscopy coupled with computational chemistry is used to provide in-depth knowledge about the cation solvation for a wide concentration range, all the way up to 5 M KFSI in DME. Starting from pure DME experimental and computed Raman spectra provides a detailed conformational assignment enabling us to calculate solvation numbers (SNs) of K+ by DME as a function of salt concentration for all the electrolytes. For low to medium KFSI concentrations, the SN is approximately constant, ca. 2.7, and/as there is a surplus of DME solvent available, while for HCEs, with much less DME available, the SN is

International audience; Immobilization of antimicrobial drug is one of the fascinating approach to expand the application of antibacterial property to consumer product. In order to stabilize antimicrobial agent, levofloxacin (LVX), into polymer substrate for sustained antibacterial activity, the drug molecules were immobilized in layered double hydroxide (LDH) and embedded in polyurethane substrate. As prepared MgAl-LDH was calcined at 400C and reconstructed with LVX for intercalation. The X-ray diffraction patterns and cross-sectional transmission electron microscopy images showed lattice expansion along the crystallographic c-axis upon LVX intercalation, suggesting the successful loading of the drug. Fourier-transformed infrared spectra revealed that intact structure of LVX was well preserved between LDH layers. Elemental analysis indicated that the loading capacity of LVX in the hybrid was 41.7%. Bacterial colony forming inhibitory assay of exhibited ~100% antibacterial activity for both LVX alone and LVX-LDH hybrid (LL) on Bacillus subtilis. To determine sustainability of antibacterial activity by the hybrid, either LVX alone or LL hybrid was loaded in polyurethane (PU) substrate of which antibacterial activity was evaluated before and after immersing in phosphate buffered saline for 3 days. The LVX composited PU showed dramatic decrease in antibacterial activity down to 0% after buffer treatment; however, LL composited PU still contained antibacterial activity (~34% of colony suppression) after phosphate buffered saline immersion.

A new robust Bi-carboxylate metal–organic framework (MOF) IEF-2 was hydrothermally prepared, acting as a proton carrier (σ ∼ 1.1 × 10−4 S cm−1). Such proton conductivity is among the highest reported so far for purely 3D carboxylate-based MOFs, being explained by the existence of a 1D hydrogen-bond network, as suggested by structural analysis and theoretical studies.

In view of potential uses in short-term thermochemical heat storage by sorption of water vapor, the capacity to release a sufficient heat amount at the appropriate rate of a Prussian blue analogue (PBA) containing hexacyanocobaltate vacancies has been compared with those of 13X type zeolites possessing Na+, Ce3+, Ce4+, or Tb3+ extra-framework compensating cations. The extended structural and surface characterization demonstrated good reproducibility of the preparation procedures performed on a 10-g scale. The adsorbents were tested under dynamic conditions of gas flow with the aid of either a gas flow calorimeter (120 mL h−1 helium flow) to measure the amount and rate of the integral heat release or a laboratory-scale test rig (15,000 to 22,800 mL h−1 nitrogen flow) to monitor the outlet temperature of nitrogen heated by adsorption. For a regeneration temperature of 353 K and a partial H2O pressure of 2.8 kPa in helium, the PBA sample yielded an integral heat ranging between 900 and 1020 kJ kg−1 with a very slow heat release lasting for even 12–14 h. The zeolite-based materials generated between 350 and 950 kJ kg−1 more rapidly (up to 6–7 h), depending on the nature and the content of compensating cations, as well as on the dehydration state achieved during regeneration. With the laboratory-scale test rig, the efficiency of heat extraction by convection was about 65% for Na-13X and only 38% for PBA, and it diminished with decreasing flow rate.

Despite the interesting chemopreventive, antioxidant and antiangiogenic effects of the natural bioflavonoid genistein (GEN), its low aqueous solubility and bioavailability make it necessary to administer it using a suitable drug carrier system. Nanometric porous metal-organic frameworks (nanoMOFs) are appealing systems for drug delivery. Particularly, mesoporous MIL-100(Fe) possesses a variety of interesting features related to its composition and structure, which make it an excellent candidate to be used as a drug nanocarrier (highly porous, biocompatible, can be synthesized as homogenous and stable nanoparticles (NPs), etc.). In this study, GEN was entrapped via simple impregnation in MIL-100 NPs achieving remarkable drug loading (27.1 wt%). A combination of experimental and computing techniques was used to achieve a deep understanding of the encapsulation of GEN in MIL-100 nanoMOF. Subsequently, GEN delivery studies were carried out under simulated physiological conditions, showing on the whole a sustained GEN release for 3 days. Initial pharmacokinetic and biodistribution studies were also carried out upon the oral administration of the GEN@MIL-100 NPs in a mouse model, evidencing a higher bioavailability and showing that this oral nanoformulation appears to be very promising. To the best of our knowledge, the GEN-loaded MIL-100 will be the first antitumor oral formulation based on nanoMOFs studied in vivo, and paves the way to the efficient delivery of nontoxic antitumorals via a convenient oral route.

International audience; Proton exchange membrane fuel cells (PEMFCs) are an attractive green technology for energy production. However, one of their mayor drawbacks is the instability of the electrolytes under working conditions (i.e., temperature and humidity). Some Metal-Organic Frameworks (MOFs) have recently emerged as promising alternative electrolyte materials due to their higher stability 2 (compared with the organic polymers, currently used as electrolyte), proton conductivity and outstanding porosity and versatility. Here, we present the ionic exchange in a microporous zirconium phosphonate UPG-1 as an efficient strategy to enhance its conductivity and cyclability. Thus, labile protons of the hybrid structure were successfully replaced by different alkali cations (Li + , Na + and K +), leading to two magnitude orders higher proton conductivity than the pristine UPG-1 (up to 2.3•10-2 S•cm-1 , which is comparable with those of the commercial electrolytes). Further, proton conductivity was strongly influenced by the MOF hydrophilicity and the polarization strength of cation, as suggested by molecular simulation. Finally, a mixed matrix membrane containing the best performing material (the potassium exchanged one) was successfully prepared, showing moderate proton conductivity (up to 8.51 10-3 S•cm-1).

A computational approach is used on MOF materials to predict the structures showing the best performances for I2 adsorption as a function of the functionalization, the pore size, the presence of the compensating ions, and the flexibility on which to base future improvements in selected materials in view of their targeted application. Such an approach can be generalized for the adsorption of other gases or vapors. Following the results from the simulations, it was evidenced that the maximum capacity of I2 adsorption by MOF solids with longer organic moieties and larger pores could exceed that of previously tested materials. In particular, the best retention performance was evidenced for MIL-100-BTB. However, if the capacity to retain traces of gaseous I2 on the surface is considered, MIL-101-2CH3, MIL-101-2CF3, and UiO-66-2CH3 appear more promising. Furthermore, the impact of temperature is also investigated.

International audience; The (photo)catalytic properties of metal–organic frameworks (MOFs) can be enhanced by post-synthetic inclusion of metallic species in their porosity. Due to their extraordinarily high surface area and well defined porous structure, MOFs can be used for the stabilization of metal nanoparticles with adjustable size within their porosity. Originally, we present here an optimized ultrafast photoreduction protocol for the in situ synthesis of tiny and monodisperse silver nanoclusters (AgNCs) homogeneously supported on a photoactive porous titanium carboxylate MIL-125-NH2 MOF. The strong metal–framework interaction between –NH2 and Ag atoms influences the AgNC growth, leading to the surfactant-free efficient catalyst AgNC@MIL-125-NH2 with improved visible light absorption. The potential use of AgNC@MIL-125-NH2 was further tested in challenging applications: (i) the photodegradation of the emerging organic contaminants (EOCs) methylene blue (MB-dye) and sulfamethazine (SMT-antibiotic) in water treatment, and (ii) the catalytic hydrogenation of p-nitroaniline (4-NA) to p-phenylenediamine (PPD) with industrial interest. It is noteworthy that compared with the pristine MIL-125-NH2, the composite presents an improved catalytic activity and stability, being able to photodegrade 92% of MB in 60 min and 96% of SMT in 30 min, and transform 100% of 4-NA to PPD in 30 min. Aside from these very good results, this study describes for the first time the use of a MOF in a visible light continuous flow reactor for wastewater treatment. With only 10 mg of AgNC@MIL-125-NH2, high SMT removal efficiency over 70% is maintained after >2 h under water flow conditions found in real wastewater treatment plants, signaling a future real application of MOFs in water remediation.

International audience; Despite the interesting chemopreventive, antioxidant and antiangiogenic effects of the natural bioflavonoid genistein (GEN), its low aqueous solubility and bioavailability make it necessary to administer it using a suitable drug carrier system. Nanometric porous Metal-Organic Frameworks (nanoMOFs) are appealing systems for drug delivery. Particularly, the mesoporous MIL-100(Fe) possesses a variety of interesting features related to its composition and structure, which make it an excellent candidate to be used as a drug nanocarrier (highly porous, biocompatible, can be synthetized as homogenous and stable nanoparticles (NPs), etc.). In this study, GEN was entrapped by simple impregnation in MIL-100 NPs achieving a remarkable drug loading (27.1 wt%). A combination of experimental and computing techniques was used to achieve a deep understanding of the encapsulation of GEN in MIL-100 nanoMOF. Subsequently, GEN delivery studies were carried out under simulated physiological conditions, showing on the whole a sustained GEN release for 3 days. Initial pharmacokinetics and biodistribution studies were also carried out upon the oral administration of the GEN@MIL-100 NPs in a mouse model, evidencing a higher bioavailability and showing that this oral nanoformulation appears very promising. To the best of our knowledge, the GEN-loaded MIL-100 will be the first antitumor oral formulation based on nanoMOFs studied in vivo, and paves the way to efficiently deliver nontoxic antitumorals by a convinient oral route. .

A novel microporous two-dimensional (2D) Ni-based phosphonate metal-organic framework (MOF; denoted as IEF-13) has been successfully synthesized by a simple and green hydrothermal method and fully characterized using a combination of experimental and computational techniques. Structure resolution by single-crystal X-ray diffraction reveals that IEF-13 crystallizes in the triclinic space group P having bi-octahedra nickel nodes and a photo/electroactive tritopic phosphonate ligand. Remarkably, this material exhibits coordinatively unsaturated nickel(II) sites, free–POH and–POH acidic groups, a CO accessible microporosity, and an exceptional thermal and chemical stability. Further, its in-deep optoelectronic characterization evidences a photoresponse suitable for photocatalysis. In this sense, the photocatalytic activity for challenging H generation and overall water splitting in absence of any co-catalyst using UV–Vis irradiation and simulated sunlight has been evaluated, constituting the first report for a phosphonate-MOF photocatalyst. IEF-13 is able to produce up to 2,200 µmol of H per gram using methanol as sacrificial agent, exhibiting stability, maintaining its crystal structure and allowing its recycling. Even more, 170 µmol of H per gram were produced using IEF-13 as photocatalyst in the absence of any co-catalyst for the overall water splitting, being this reaction limited by the O reduction. The present work opens new avenues for further optimization of the photocatalytic activity in this type of multifunctional materials. [Figure not available: see fulltext.]., This work was supported by MOFseidon project (Retos project, PID2019-104228RB-I00, MICIU-AEI/FEDER, UE), and the Ramón Areces Foundation project H+MOFs. P. H. acknowledges the Spanish Ramón y Cajal Programme (2014-15039). S. N. thanks financial support by the Fundación Ramón Areces (XVIII Concurso Nacional para la Adjudicación de Ayudas a la Investigatión en Ciencias de la Vida y de la Materia, 2016), Ministerio de Ciencia, Innovatión y Universidades RTI2018–099482-A-I00 project and Generalitat Valenciana grupos de investigación consolidables 2019 (AICO/2019/214) project and Agència Valenciana de la Innovació (AVI, INNEST/2020/111) project. H. G. thanks financial support to the Spanish Ministry of Science and Innovation (Severo Ochoa and RTI2018-098237-CO21) and Generalitat Valenciana (Prometeo2017/083). In memory of our dear colleague, Prof. Emilio Morán, who recently passed away.

International audience; Systematic utilization of carbonated Mg–Al layered double hydroxide (LDH) nanosheets for methyl orange removal was investigated with respect to particle dimensions. LDHs with the smallest dimensions were carefully synthesized to have a small lateral size as well as high dispersibility. The other particles, with medium and large sizes, were prepared by hydrothermal treatment and urea hydrolysis to have larger sizes and higher crystallinity. According to kinetics and isotherm analyses, the smallest LDH showed efficient adsorption of methyl orange (1250 mg/g-LDH), which was remarkably higher than the adsorption by the other LDHs with larger lateral sizes. Unlike the larger lateral-sized LDHs, the small ones were shown to utilize all accessible adsorption sites on the nanosheets, generating nanoconfinement of methyl orange molecules. Transmission electron microscopy (TEM) and powder X-ray diffraction (PXRD) patterns indicated that the LDHs with lateral dimensions of ~40 nm fully utilized interlayer nanospace. Monte Carlo simulation suggested that the intercalated methyl orange was stabilized not only through electrostatic interactions with the LDH layer but also by π-π stacking between the methyl orange molecules, which is thought to be the driving force for replacement of carbonate anions.

Proton exchange membrane fuel cells (PEMFCs) are an attractive green technology for energy generation. The poor stability and performances under working conditions of the current electrolytes are their major drawbacks. Metal-Organic Frameworks (MOFs) have recently emerged as an alternative to overcome these issues. Here, we propose a robust Zr-phosphonate MOF (UPG-1) bearing labile protons able to acta priorias an efficient electrolyte in PEMFCs. Further, in an attempt to further enhance the stability and conductivity of UPG-1, a proton carrier (the amino acid Lysine, Lys) was successfully encapsulated within its porosity. The behaviors of both solids as an electrolyte were investigated by a complete experimental (impedance spectroscopy, water sorption) and computational approach (MonteCarlo, water sorption). Compared with the pristine UPG-1, the newly prepared Lys@UPG-1 composite showed similar proton conductivity but a higher stability, which allows a better cyclability. This improved cyclability is mainly related to the different hydrophobic-hydrophilic balance of the Lys@UPG-1 and UPG-1 and the steric protection of the reactive sites of the MOF by the Lys. This research was funded by Raphuel project (ENE2016-79608-C2-1-R, MINECO-AEI/FEDER, UE), a 2017 Leonardo Grant for Researchers and Cultural Creators BBVA Foundation (PolyMOF) and the Ramón Areces Fundation project H+MOFs. PH acknowledges the Spanish Ramon y Cajal Programme (2014-16823). SMFV thanks to the Spanish Ministerio de Educación, Cultura y Deporte for “José Castillejo” mobility programme (Ref. CAS18/00470) Publicado

The potential use of commercially available 13X zeolite, modified by ion-exchange with cerium compensating cations possessing high charges and high hydration energies, has been tested in view of low-temperature storage of solar energy performed under mild operating conditions of low regeneration temperatures and low pressures of water vapour during the adsorption step. Structural and textural properties, sorption behaviour towards water vapour of three selected samples containing various proportions of Ce3+ and Ce4+ compensating cations and the pristine Na+-13X zeolite were studied by a variety of experimental techniques including Wavelength Dispersive X-Ray Fluorescence, Energy Dispersive X-ray Spectroscopy, X-ray diffraction, Thermogravimetric analysis, as well as measurements of the adsorption of gaseous nitrogen at 77 K and water vapour at 313 K. Based on the structure refinement procedure applied to the experimental XRD patterns, it was demonstrated that extra-framework cerium cations were preferentially located on sites I’ and II in dry and hydrated zeolites, showing relatively little dependence on the hydration level. Monte Carlo simulations were used to determine the limit values of the amount adsorbed and differential heat of adsorption, which could be obtained experimentally if the zeolite samples were completely dried. The potential of Ce-containing zeolites as adsorbents for the thermochemical energy storage was finally determined under flow conditions by firstly dehydrating samples at 353 K or 423 K and then saturating them at 296 K with water vapour at a mole fraction of 0.03. The choice of the operating conditions was decided so as to maintain the stability of the zeolite structure while taking the risk of reduced thermal performance of zeolite adsorbents undergoing incomplete regeneration-dehydration. Under such mild conditions, the modified 13X zeolites exhibited enhanced thermal performance in comparison with that of the pristine 13X, by releasing between 700 and 1100 kJ per kg of the adsorbent during a period of 6–8 h. Through a complementary study based on calorimetry measurements and molecular simulations, the understanding of the hydration-dehydration steps in Ce-exchanged zeolites and cation displacement upon hydration has allowed to establish the best compromise for the conditions of zeolite regeneration and saturation in the case of heat long-term storage applications.

We report the postsynthetic functionalization of Prussian blue (PB) nanoparticles by two different luminophores (2-aminoanthracene and rhodamine B). We show that the photoluminescence properties of the fluorophores are modified by a confinement effect upon adsorption and demonstrate that such multifunctional nanosized systems could be used for in vitro imaging.

International audience; We report the post-synthetic functionalization of Prussian blue (PB) nanoparticles by two different luminophores (2-aminoanthracene and rhodamine B). We show that the photoluminescence properties of the fluorophores are modified by a confinement effect upon adsorption and demonstrate that such multifunctional nanosized systems could be used for in vitro imaging.

International audience; In the present study, the synthesis of microporous zinc imidazolate nanoparticles was assessed with and without the presence of ibuprofen or 5-fluorouracil (5-FU) anticancer drug. The drugs loading was ensured by thermogravimetric analysis, nitrogen adsorption/desorption. The crystalline structure of the different prepared materials was monitored by using X-ray powder diffraction. Up to 5% loading (molar ratio of drug/Zn 2+), there was no evidence of crystalline drugs in the XRD patterns, suggesting an optimized occupation of the ZIF-8 cells. The pattern of the samples remained identical with and without drug. Particle size ranging between 30 and 95 nm could be deduced according to the Scherrer equation. It was found to depend on the dilution of the reagents, but also on the presence of drugs in the synthesis medium. The morphology of the samples was presented by using scanning and transmission electron microscopies, confirming the size obtained using XRD. The presence of drugs induced a significant increase in the particle size of the synthesized materials; however, those sizes are still in range for drug delivery application (< 200 nm). The drugs@ZIF-8 nanoparticles were found to be hexagonal or cubic shaped, depending on the reaction duration.

Theoretical and experimental characterization methods have been combined to shed more light on the potential impact of the various templating amines that they may have on the formation of layered v...

The present paper examines the impact that the nanotube morphology and organic or inorganic intercalated species may have on the cesium sorption by layered vanadium oxides prepared with the use of hexadecylamine as a structure-directing agent. The hybrid material represented by a chemical formula of (V2O5)(VO2)1.03(C16H36N)1.46(H2O)x was achieved through accelerated microwave-assisted synthesis carefully optimized to ensure the best compromise between the scroll-like morphology and the hydrophobic character. To enhance its dispersibility in water, this sample was subsequently modified by progressive replacement of the C16H36N+ units by NH4+ cations. The final materials represented a stacking of lamellar sheets with a worse scroll-like morphology. Both the optimization procedure and the template removal were monitored on the basis of scanning and transmission electronic microscopy, X-ray diffraction, infra-red spectroscopy, inductively coupled plasma-optical emission spectrometry, X-ray photoelectron spectroscopy, and elemental analysis, supplemented by adequate simulations methods providing the reference IR spectra and XRD patterns for comparison or the textural parameters of the samples. The comparison of the cesium sorption from either a 4:1 ethanol–water mixture or aqueous solutions pointed toward the solubility of intercalated cations in the bulk solution as the main factor limiting their displacement from the interlayer space by the oncoming cesium ones. The sample obtained after 70% exchange with NH4+ exhibited a maximum sorption capacity of 1.4 mmol g−1 from CsNO3 aqueous solutions and its retention efficiency remained significant from low-concentration Cs solutions in river or sea water.

We demonstrate here that Mn

[EN] Despite the higher efficiency, larger color range and faster stimulus response of polymeric electrochromic materials, their poor cyclability strongly hampers their application in optoelectronics. As an original strategy to stabilize and further nanostructure these polymers, herein an efficient encapsulation and in situ polymerization inside highly porous metal-organic frameworks (MOFs) is reported. In particular, the successful accommodation of poly(3,4-ethylendioxythiophene) (PEDOT) and its partially oxidized polarons inside the mesopores of the nontoxic iron trimesate MIL-100(Fe) is convincingly proved by a large panel of experimental techniques. Remarkably, the polymer-MOF interaction occurring for entrapped PEDOT within the pores (deeply assessed by experimental and simulation methods) might be responsible for the enhanced electrical conductivity of the resulting PEDOT@MIL-100(Fe) composite when compared to the insulating MIL-100(Fe) and the conductive free PEDOT. Furthermore, it was possible to observe the electrochromic properties of the PEDOT@MIL-100(Fe) composite, achieving an improved stability and good cyclability as a consequence of the effective protection by the MOF matrix., This work was supported by a 2017 Leonardo Grant for Researchers and Cultural Creators, BBVA Foundation (IN[17]_CBB_QUI_0197). The work was also partially supported by IMDEA Energy and Raphuel project (ENE2016-79608-C2-1-R, MINECOAEI/FEDER, UE). PH acknowledges the Spanish Ramon y Cajal Programme (grant agreement no. 2014-16823). S. N. thanks the Spanish Ministerio de Educacion, Cultura y Deporte for Jose Castillejo mobility programme (CAS14/00067) and financial support by Fundacion Ramon Areces (XVIII Concurso Nacional para la Adjudicacion de Ayudas a la Investigacion en Ciencias de la Vida y de la Materia, 2016). We also thank the synchrotron Soleil for providing access to the Cristal beamline.

An alternative microwave-assisted hydrothermal route for the preparation of manganate nanoflowers under basic conditions has been proposed in view of potential uses in selective retention of strontium from multicomponent aqueous streams. Based on the combination of such characterization techniques as Scanning and Transmission Electronic Microscopy, X-ray photoelectron spectroscopy, and X-ray Diffraction, as well as taking advantage of the computer-aided structure simulation, homogeneous nanoflower morphology possessing a layered structure and K+ compensating cations was evidenced as corresponding to the KMn4O8 chemical formula. The nanoflower sample was subsequently tested for the selective adsorption of strontium and cesium by measuring the individual adsorption isotherms from single-solute and multicomponent aqueous solutions. The material appeared selective towards strontium against cesium even in multicomponent solutions provided that the concentration of calcium remained low. This difference in the retention selectivity was rationalized based on the Density Functional Theory (DFT) calculations of the energy of adsorption and direct calorimetry measurements of the enthalpy of displacement for the individual cations.

In this communication, we report the post-synthetic functionalization of K+/Ni2+/[Cr(CN)6]3- Prussian blue analogue (PBA) nanoparticles by the 2-aminoanthracene luminophore to yield a bifunctional magneto-luminescent nanosystem. The photoluminescence properties of the fluorophore are found modified by the confinement effect upon adsorption, while the magnetic behavior of PBA is preserved.

International audience; Among thermosetting polymers, epoxy resins are major components of adhesives, sealants, paints and composites. Polymerization is often achieved by reaction of epoxy monomers like DGEBA with amine hardeners such as DETA. Previous works showed that polyamines interact with metal (hydr/oxide) substrates leading to the formation of an interphase involving the chelation of surface metal ions. In this work, we further explored the interaction between DETA and aluminum (hydr)oxide, denoted Al, via a combined experimental and modeling approach. We inspected in depth by DSC the modifications of glass transition temperature Tg and change in heat capacity ΔCp after curing, allowing us quantifying the impact of Al amount on DGEBA/DETA degree of cure α. A new parameter, the “percentage of inhibition of cure” denoted , was defined reaching up to ~4 % in our experimental conditions. In parallel, in situ mixing calorimetry confirmed the exothermic character of DETA interaction with Al with various degrees of division. DFT calculations were carried out to examine DETA/Al3+ chelates. Among plausible chelate configurations, one was associated with a lower conformational energy and shorted Al-N bond lengths, suggesting greater stability. Calculated and experimental Raman spectra were additionally investigated, allowing us to discuss further about the DETA/Al3+ chelates at play.