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Composites based on chitin (CH) biopolymer and metal-organic framework (MOF) microporous nanoparticles have been developed as broad-scope pollutant absorbent. Detailed characterization of the CH/MOF composites revealed that the MOF nanoparticles interacted through electrostatic forces with the CH matrix, inducing compartmentalization of the CH macropores that led to an overall surface area increase in the composites. This created a micro-, meso-, and macroporous structure that efficiently retained pollutants with a broad spectrum of different chemical natures, charges, and sizes. The unique prospect of this approach is the combination of the chemical diversity of MOFs with the simple processability and biocompatibility of CH that opens application fields beyond water remediation.

Poly(vinylidene fluoride) (PVDF) and MOF-808-based separators for lithium-ion batteries (LIBs) have been prepared and fully characterized in terms of morphological and thermal properties, electrolyte uptake, and retention, and surface hydrophilic characteristics. The effect of PVDF/MOF-808 separators on the electrochemical performance of LIBs has been evaluated. The PVDF/MOF-808 membranes exhibit a well-defined porous structure with a uniform distribution of interconnected macro- to mesopores. The inclusion of the Zr-based MOF nanoparticles increases the porosity and surface area of the separator, enhancing the electrolyte uptake and the ionic conductivity. Finally, the presence of MOF-808 fillers improves the liquid electrolyte retention, which prevents the capacity fading at high C-rates cycling. Indeed, charge–discharge tests performed in Li/C-LiFePO4 half-cells reveal a discharge capacity of 68 mAh·.g–1 at 2C-rate for PVDF/MOF-808 membranes, in comparison with the 0 mAh·g–1 obtained for pure PVDF. The PVDF/10 wt % MOF-808 sample shows a long-term stable cycling behavior with a Coulombic efficiency close to 100%. Thus, it is shown that the composite membranes represent an improvement with respect to conventional separators for lithium ion battery applications, since they coupled the polymer meso- and macroporous structure with the well-ordered microporous system of the MOFs, which improve significantly the electrolyte affinity, FCT (Fundação para a Ciência e Tecnologia) for financial support under the framework of Strategic Funding grants UID/FIS/04650/2019, and UID/QUI/0686/2019 and project PTDC/FIS-MAC/28157/2017. The author also thanks the FCT for financial support under grant SFRH/BPD/112547/2015 (C.M.C.) and Investigator FCT Contract CEECIND/00833/2017 (R.G.). A.V. thanks to the Basque Government Education department for her pre-doctoral grant. The European Commission Research & Innovation H2020-MSCA-RISE-2017 (Ref.: 778412) INDESMOF project is also acknowledged. Financial support from the Basque Government Industry and Education Departments under the ELKARTEK (ACTIMAT and LION), HAZITEK (SIMAM) and PIBA (PIBA-2018-06- LIMOFILM)

Spanish Ministry of Economy and Competitiveness (MINECO) (AEI/FEDER, UE) (FEDER) MAT2016-76739-R MAT2016-76039-C4-3-R Basque Government Industry and Education Departments PIBA-2018-06 European Commission Research & Innovation H2020-MSCA-RISE-2017 INDESMOF project 778412

The demand for more efficient energy storage devices has led to the exponential growth of lithium-ion batteries. To overcome the limitations of these systems in terms of safety and to reduce environmental impact, solid-state technology emerges as a suitable approach. This work reports on a three-component solid polymer electrolyte system based on poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP), the ionic liquid 1-butyl-3-methylimidazolium thiocyanate ([BMIM][SCN]), and clinoptilolite zeolite (CPT). The influences of the preparation method and of the dopants on the electrolyte stability, ionic conductivity, and battery performance were studied. The developed electrolytes show an improved room temperature ionic conductivity (1.9 × 10–4 S cm–1), thermal stability (up to 300 °C), and mechanical stability. The corresponding batteries exhibit an outstanding room temperature performance of 160.3 mAh g–1 at a C/15-rate, with a capacity retention of 76% after 50 cycles. These results represent a step forward in a promising technology aiming the widespread implementation of solid-state batteries., FCT (Fundação para a Ciência e Tecnologia) for financial support under the framework of Strategic Funding grants UID/CTM/50025/2021, UID/FIS/04650/2021, UID/EEA/04436/2021 and UID/QUI/0686/2021; and support from FEDER funds through the COMPETE 2020 Programme (projects PTDC/FISMAC/28157/2017 and POCI-01-0145-FEDER-007688). Grants SFRH/BD/140842/2018 (J.C.B.) and SFRH/BPD/121526/2016 (D.M.C) and contracts under the Stimulus of Scientific Employment, Individual Support CEECIND/00833/2017 (R.G.) and 2020.04028 CEECIND (C.M.C.) are acknowledged. Financial support from the Basque Government under the ELKARTEK program, Basque University System Research Groups, IT-1290-19 and the University of the Basque Country (GIU18/197). is also acknowledged

The versatility of CuBTC (or HKUST-1) MOF materials to be functionalized to tune their catalytic activity performance was evaluated. The MOFs were functionalized with ionic liquids (ILs) to give rise to catalysts able to adsorb CO2 and react with epoxides to produce carbonates. The materials are active for this reaction and show good conversion rates at 100 °C and 7 bar CO2, confirming their ability to fix this gas and transform it into valuable products. In addition, the MOF@IL composite material 1 can be functionalized to give rise to a bimetallic catalyst, taking advantage of the N-heterocyclic carbene present in the imidazolium-based ILs. Therefore, the material was reacted with palladium dichloride, yielding CuBTC@IL-(NHC)Pd (1Pd) which has been tested for homocoupling of alkynes and imination of benzyl alcohol reactions. The recyclability of the catalysts has been studied and hot filtration tests have been made.

Circular economy paradigms will benefit materials with multifunctional properties allowing to be implemented in more than one application, after processed, or in one application after already being used in another. In this context, membranes based on TiO2/poly(vinylidene fluoride‐co‐trifluoroethylene) (PVDF‐TrFE) with different filler contents were prepared for battery and photocatalytic degradation of pollutants by a temperature‐induced phase separation process (TIPS). It has been shown that the morphological, thermal and mechanical properties, porosity, contact angle, the ionic conductivity and lithium transference number are dependent on the TiO2 content. The membranes with 10 wt% TiO2 content show an ionic conductivity of 0.59 mS cm−1, lithium transference number of 0.72, discharge capacity of 128 mAh g−1 and low capacity fade (17%) at 2C. Further, this membrane presents a high photocatalytic response, being able to be used for ciprofloxacin remediation from water after 300 min of exposure to UV. Further, a second life was confirmed for this membrane by being implemented as a lithium ion battery separator after its use for water remediation applications. This work explores a new concept for the efficient use of the same membranes in very different applications, demonstrating the multifunctionality of the material in the scope of the circular economy paradigm.

International audience; In the endless possibility space of metal organic framework design, the quest for new multifunctional materials with desirable properties is still ongoing. At the environmental level, their development poses a promising industrial alternative for the management of aqueous pollutants and for storage and separation of gases. In this context, the recently reported porphyrinic framework 1, [Ni5(H2TCPP)2O(H2O)4]•nS (where H6TCPP is meso-tetra(4-carboxyphenyl)porphyrin and S is the solvent) is investigated through a fundamental study of its thermal and magnetic properties, together with its potential as an adsorbent for pollutants in the liquid and gas phase. Sorption of four organic dye solutions with different chemical features was carried out, with good affinity found towards small cationic species. In addition, a series of different gases (N2, O2, CO, CO2, C1-C4 hydrocarbons) were tested through the use of adsorption microcalorimetry in order to understand the interactions and selectivity of 1. This study affords an in-depth approach to the characterization of a new selective adsorbent for pollutants of industrial interest.

The presence of hexavalent chromium water pollution is a growing global concern. Among the currently applied technologies to remove CrVI, its adsorption and photocatalytic reduction to CrIII less mobile and toxic forms are the most appealing because of their simplicity, reusability, and low energy consumption. However, little attention has been paid to bifunctional catalysts, that is, materials that can reduce CrVI to CrIII and retain both hexavalent and trivalent chromium species at the same time. In this work, the dual CrVI adsorption–reduction capacity of two iconic photoactive water-stable zirconium and titanium-based metal–organic frameworks (MOFs) has been investigated: UiO-66-NH2 and MIL-125. The bifunctionality of photoactive MOFs depends on different parameters, such as the particle size in MIL-125 or organic linker functionalization/defective positions in UiO-66 type sorbents. For instance, the presence of organic linker defects in UiO-66 has shown to be detrimental for the chromium photoreduction but beneficial for the retention of the CrIII phototransformed species. Both compounds are able to retain from 90 to 98% of the initial chromium present at acidic solutions as well as immobilize the reduced CrIII species, demonstrating the suitability of the materials for CrVI environmental remediation. In addition, it has been demonstrated that adsorption can be carried out also in a continuous flux mode through a diluted photoactive MOF/sand chromatographic column. The obtained results open the perspective to assess the bifunctional sorption and photoreduction ability of a plethora of MOF materials that have been applied for chromium capture and photoreduction purposes. In parallel, this work opens the perspective to develop specific chemical encoding strategies within MOFs to transfer this bifunctionality to other related water remediation applications. The authors thank the financial support from the Spanish Ministry of Economy and Competitiveness (MINECO) through projects MAT2016-76739-R (AEI/FEDER, EU) and MAT2016-76039-C4-3-R (AEI/FEDER, UE) (including FEDER financial support) and from the Basque Government Industry and Education Departments under the ELKARTEK (LION, ACTIMAT), HAZITEK (SIMAN) and PIBA (PIBA-2018-06) programs, respectively. The European Commission Research & Innovation H2020-MSCA-RISE-2017 (Ref.: 778412) INDESMOF project.

The search of natural materials for their application in energy storage systems in general and batteries in particular is growing due to their promising properties and the need of environmental sustainability. Silk fibroin (SF) is one of those materials due to their mechanical and thermal properties, non-toxicity and biocompatibility. Further, SF exhibits excellent cycling performance as separator for lithium-ion battery applications. This work reports on SF membranes with different pore sizes (within the rages: 38–22, 106–38 and 250-106 μm) prepared for separators in lithium-ion batteries. The morphology, structure and thermal properties were evaluated. It is shown that the β-sheet conformation percentage increases with increasing pore size, which also leads to higher electrolyte uptake, reaching 350% for SF membranes with pore size of 250–106 μm. With respect to battery performance, a high discharge capacity (131.3 mAh g−1, for C/8) is obtained for this membrane, FCT (Fundação para a Ciência e Tecnologia) for financial support under the framework of Strategic Funding grants UID/FIS/04650/2019, and UID/QUI/0686/2019 and project PTDC/FIS-MAC/28157/2017. The author also thanks the FCT for financial support under grant SFRH/BPD/112547/2015 (C.M.C.) and Investigator FCT Contract CEECIND/00833/2017 (R.G.). Financial support from the Spanish Ministry of Economy and Competitiveness (MINECO) through project MAT2016-76039-C4-3-R (AEI/FEDER, UE) (including FEDER financial support) and from the Basque Government Industry and Education Departments under the ELKARTEK, HAZITEK and PIBA (PIBA-2018-06)

Heterogeneous catalysts are of great interest in many industrial processes for environmental reasons and, during recent years, a great effort has been devoted to obtain metal–organic frameworks (MOFs) with improved catalytic behaviour. Few supramolecular metal–organic frameworks (SMOFs) are stable under ambient conditions and those with anchored catalysts exhibit favourable properties. However, this paper presents an innovative approach that consists of using metal nodes as both structural synthons and catalysts. Regarding the latter, metalloporphyrins are suitable candidates to play both roles simultaneously. In fact, there are a number of papers that report coordination compounds based on metalloporphyrins exhibiting these features. Thus, the aim of this bioinspired work was to obtain stable SMOFs (at room temperature) based on metalloporphyrins and explore their catalytic activity. This work reports the environmentally friendly microwave-assisted synthesis and characterization of the compound [H(bipy)]2[(MnTPPS)(H2O)2]·2bipy·14H2O (TPPS = meso-tetraphenylporphine-4,4′,4′′,4′′′-tetrasulfonic acid and bipy = 4,4′-bipyridine). This compound is the first example of an MnTPPS-based SMOF, as far as we are aware, and has been structurally and thermally characterized through single-crystal X-ray diffraction, IR spectroscopy, thermogravimetry and transmission electron microscopy. Additionally, this work explores not only the catalytic activity of this compound but also of the compounds μ-O-[FeTCPP]2·16DMF and [CoTPPS0.5(bipy)(H2O)2]·6H2O. The structural features of these supramolecular materials, with accessible networks and high thermal stability, are responsible for their excellent behaviour as heterogeneous catalysts for different oxidation, condensation (aldol and Knoevenagel) and one-pot cascade reactions.

Two closed and one open structural forms of the interpenetrated [Cu2(Tae)(Bpa)2](NO3)2·nH2O (H2Tae = 1,1,2,2-tetraacetylethane, Bpa = 1,2-bis(4-pyridyl)ethane) cationic coordination polymer have been synthesized. Three crystallographically related interpenetrated “ths” cationic nets encapsulate water molecules and nitrate anions giving rise to the closed structural forms of [Cu2(Tae)(Bpa)2](NO3)2·nH2O. Depending on the location of water molecules and nitrate groups, two different closed forms with 5.5 and 3.6 crystallization water molecules have been obtained. The thermal activation of the closed structures gives rise to a 29% expansion of the unit cell. This closed to open transformation is reversible, and is triggered by the loss or uptake of solvent. The high pressure gas adsorption experiments show similar selectivity values towards CO2 for CO2/CH4 mixtures to that showed by some metal organic frameworks without unsaturated metal sites, and isosteric heats for CO2 adsorption similar to that for the HKUST-1 compound.

Sustainable materials are increasingly needed in lithium ion batteries in order to reduce their environmental impact and improve their recyclability. This work reports on the production of separators using poly (L-lactic acid) (PLLA) for lithium ion battery applications. PLLA separators were obtained by solvent casting technique, by varying polymer concentration in solution between 8 wt.% and 12 wt.% in order to evaluate their morphology, thermal, electrical and electrochemical properties. It is verified that morphology and porosity can be tuned by varying polymer concentration and that the separators are thermally stable up to 250 ºC. The best ionic conductivity of 1.6 mS/cm was obtained for the PLLA separator prepared from 10 wt.% polymer concentration in solution, due to the synergistic effect of the morphology and electrolyte uptake. For this membrane, a high discharge capacity value of 93 mAh.g-1 was obtained at the rate of 1C. In this work, it is demonstrated that PLLA is a good candidate for the development of separator membranes, in order to produce greener and environmentally friendly batteries in a circular economy context., Work supported by the Portuguese Foundation for Science and Technology (FCT) undes strategic funding UID/FIS/04650/2020 and UID/QUI/0686/2020, project PTDC/FISMAC/28157/2017, and Grants SFRH/BD/140842/2018 (J.C.B.), SFRH/BPD/121526/2016 (D.M.C), CEECIND/00833/2017 (R.G.) and SFRH/BPD/112547/2015 (C.M.C.). Financial support from the Basque Government Industry Department under the ELKARTEK and HAZITEK programs is also acknowledged. Technical and human support provided by SGIker (UPV/EHU, MICINN, GV/EJ, EGEF and ESF) is gratefully acknowledged

Metal-Organic Frameworks (MOFs) are porous coordination networks assembled through metal complexes with organic linkers. Due to their chemical versatility, these materials are being investigated for various applications including gas storage and separation, biomedicine and catalysis. The aim of this work is the encapsulation of the model β-alanine amino-acid in the nanostructured zirconium-based MOF (UiO-66) which contains the ligand H2BDC (1,4-benzenedicaboxylic acid). Additionally, ligand functionalization (by using H2doBDC (2,5-dihydroxy-1,4-benzenedicarboxylic acid) and defect engineering have been carried out to produce UiO-66 derivatives, in order to modify the host-guest interactions, and hence study their influence on the β-alanine loading capacity and release kinetics. The as-obtained materials have been characterized by X-ray diffraction (XRD), X-ray thermo diffraction (TDX), infrared (IR) spectroscopy, thermogravimetric analysis-differential scanning calorimetry (TG-DSC) and elemental analysis (EA). Morphology of nanoscale MOFs has been explored by transition electron microscopy (TEM). Adsorption isotherms have been constructed, and the concentration of β-alanine in the post-adsorption solution (supernatant) has been quantified by high performance liquid chromatography coupled with mass spectroscopy (HPLC-MS) and EA. Adsorption capacity values indicate that the presence of hydroxyl groups at the organic linker H2doBDC enhances the host-guess affinity between the framework and the adsorbate β-alanine. The influence of defect engineering, on the adsorption however, is not that obvious. On the other hand, desorption experiments show similar behaviour for H2doBDC-based derivatives. An adsortion mechanism has been proposed consisting of a combination of host-guest interaction at low concentrations, and covalent anchoring/ligand displacement by β-alanine at the inorganic clusters. Ministerio de Economía y Competitividad [MAT2016-76739-R (AEI/FEDER, UE)]; Universidad del País Vasco/ Euskal Herriko Unibertsitatea (GIU 18/197); Gobierno Vasco ELKARTEK-ACTIMAT, HAZITEK-SIMAN and PIBA-LIMOFILM (PIBA-2018-06).

Metal organic frameworks (MOFs) are crystalline materials based on connections between metal ions through organic ligands. The combination of polycarboxylate anions and dipyridyl ligands is an effective strategy for producing extended structures. In this sense, the combination of bpa with m-bdc [bpa = 1,2-bis(4-pyridyl)ethane, m-bdc = 1,3-benzenedicarboxylate] has produced three new CuII-based networks with different dimensionalities, namely the 1D [Cu(m-bdc)(bpa)0.5(H2O)dmf]·0.5H2O (1, synthesis based on sonication and slow evaporation), the 2D [Cu6(m-bdc)6(bpa)6(dmf)3]·8dmf (2, microwave synthesis) and the 3D [Cu4(m-bdc)4(bpa)2dmf]·dmf (3, microwave synthesis). The three compounds have been structurally characterized by means of single-crystal X-ray diffraction, IR and UV/Vis spectroscopy and elemental analysis. An unprecedented CuII dimer has been observed for compound 3. The thermal behaviour of the compounds was analysed by thermogravimetry (TG/DSC) and X-ray thermodifractometry (TDX), and it was concluded that the dimensionality plays an important role in their thermal properties. Electronic paramagnetic resonance and magnetic susceptibility measurements for compounds 1 and 3 showed that antiferromagnetic interactions exist between the metal ions.

Poly(vinylidene fluorideco-trifluoroethylene) (P(VDF-TrFE)) microspheres were obtained by a nanoprecipitation method based on the deposition of a polymeric solution over a non-solvent (NS) solution. The effect of several parameters on sphere formation was evaluated, including copolymer concentration, NS content (methanol/water ratio) and surfactant type. Morphological and physico-chemical characterizations were performed. Depending on processing conditions, spheres with diameters ranging from ~100 to 1100nm with similar physico-chemical properties were obtained. Independently of the processing conditions, P(VDF-TrFE) microspheres crystallize in the electroactive phase with an average crystallinity of 26%. Thus, samples show the required characteristics for biomedical applications., Fundação para a Ciência e Tecnologia (FCT); UID/FIS/04650/2019, UID/EEA/04436/2019, PTDC/BTM-MAT/28237/2017, PTDC/EMDEMD/28159/2017 and POCI-01-0145-FEDER-028159. FCT is also acknowledged by E.O.C. and D.M.C. for the grants SFRH/BD/145455/2019 and SFRH/BPD/121526/2016, respectively. The Spanish Ministry of Economy and Competitiveness (MINECO): project MAT2016-76039-C4-3-R (AEI/FEDER, UE). Basque Government Industry and Education Departments: ELKARTEK, HAZITEK and PIBA., info:eu-repo/semantics/publishedVersion

Heterogeneous catalysts are a great bet for green chemistry in many industrial processes and, in the past decade, promising results have been achieved in order to improve the catalytic activity of Metal Organic Frameworks (MOFs). Accordingly, porphyrins make possible to design new coordination polymers with better properties, taking into account the important functions they develop in nature. In this sense, porphyrin-based MOFs are becoming very relevant in heterogeneous catalysis. Thus, the aim of this work was obtaining metalloporphyrinic MOFs exhibiting catalytic activity. Studying the effect of dimensionality on the MOF properties (including thermal stability and catalytic activity), in this work we study two catalysts with different dimensionalities, 3D [Ni5(H2TCPP)2O(H2O)4]•nS (1) and 0D [Cu(H4TCPP)]•6DMF (2) (where H6TCPP is meso-tetra(4-carboxyphenyl)porphyrin, DMF is N,N-dimethylformamide and S is the solvent). The structural features of both compounds, combined with their high thermal stability and accessible networks, are responsible for the excellent behaviour as heterogeneous catalysts. It is worth mentioning that significant reduction in reaction time compared to other reported catalysts has been observed. The recyclability of one of the herein studied porphyrin-based MOFs is outstanding. Further structural and thermal characterization has been carried out by means of single crystal X-ray diffraction, IR spectroscopy, thermogravimetry (TG), powder X-ray diffraction (XRD) and transmission electron microscopy (TEM). Ministerio de Economia, Industria y Competitividad (MAT2016-76739-R) Gobierno Vasco’’ (Basque University System Research Groups, IT-630-13)

Metalloporphyrins exhibit outstanding chemical, physical and biological properties in dissolution, however, it is a challenge to synthesize them as stable solid frameworks. Long-time stability is crucial for future applications of these materials, and we have detected a slow, solid-state transformation of a 2D MnII-porphyrin at RT. The remarkable point is that this transformation showed up as a result of Electronic Paramagnetic Resonance measurements. Otherwise, the evolution of the system could have remained undetected. Thus, 2D [Mn3(TCPP)(H2O)4]•nD (1) (where TCPP is meso-tetra(4-carboxyphenyl)porphyrin and D is the sovent) has been synthesized hydrothermally, and characterised by means of X-ray diffraction (XRD), Thermogravimetry and X-ray thermodiffractometry (XRTD). This compound slowly transforms into [Mn(H4TCPP)(H2O)2]•nD (2) according to the equilibrium [Mn3(TCPP)]+4H+ ↔ [Mn(H4TCPP)]+2Mn2+. The evolution of the system has been studied through analysis of the distortion (both of the coordination sphere and the tetrapyrrolic macrocycle) and Density Functional Theory (DFT) quantum mechanical calculations. Ministerio de Economia y Competitividad (MAT2013-42092-R), Gobierno Vasco (Basque University System Research Groups, IT-630-13) and UPV/EHU (UFI11/15)

CuII nanoballs have been determined to be among the best MOPs (Metal–Organic Polyhedra) reported so far for the adsorption of small molecules, with the highlighting advantage of rapid kinetics, which focuses on their applicability to the removal of emerging pollutants. Ministerio de Economia y Competitividad (MAT2013-42092-R), Gobierno Vasco (Basque University System Research Groups, IT-630-13) and UPV/EHU (UFI11/15)