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This project has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (NanoMOFdeli), ERC-2016-COG 726380, Innovate UK (104384) and EPSRC IAA (IAA/RG85685). N.R. acknowledges the support of the Cambridge International Scholarship and the TrinityHenry Barlow Scholarship (Honorary). O.K.F. and R.Q.S. acknowledge funding from the U.S. Department of Energy (DE-FG02-08ER15967). R.S.F. and D.B. acknowledge funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (SCoTMOF), ERC-2015-StG 677289. Sandia National Laboratories is a multimission laboratory managed and operated by National Technology and Engineering Solutions of Sandia, LLC., a wholly owned subsidiary of Honeywell International, Inc., for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-NA-0003525. The authors gratefully acknowledge funding from the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Hydrogen and Fuel Cell Technologies Office, through the Hydrogen Storage Materials Advanced Research Consortium (HyMARC). This paper describes objective technical results and analysis. Any subjective views or opinions that might be expressed in the paper do not necessarily represent the views of the U.S. Department of Energy or the United States Government. J.D.E. acknowledges the support of the Alexander von Humboldt Foundation and the Center for Information Services and High Performance Computing (ZIH) at TU Dresden. S.K.G. and S.M. acknowledge SERB (Project No. CRG/2019/000906), India for financial support. K.K. and R.K. acknowledge Active Co. Research Grant for funding. S.K. acknowledges funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (COSMOS), ERC-2017-StG 756489. N.L. and J.G.M acknowledge funding from the European Commission through the H2020-MSCA-RISE-2019 program (ZEOBIOCHEM -872102) and the Spanish MICINN and AEI/FEDER (RTI2018-099504-B-C21). N.L. thanks the University of Alicante for funding (UATALENTO17-05). ICN2 is supported by the Severo Ochoa program from the Spanish MINECO (Grant No. SEV-2017-0706) S.M.J.R. and A.L. wish to thank the Fund for Scientific Research Flanders (FWO), under grant nos. 12T3519N and 11D2220N. L.S. was supported by the EPSRC Cambridge NanoDTC EP/L015978/1. C.T.Y. and T.S.N. acknowledges funds from the National Research Foundation of Korea, NRF-2017M3A7B4042140 and NRF-2017M3A7B4042235. P.F. and H. Y. acknowledge US Department of Energy, Office of Basic Energy Sciences, Materials Sciences and Engineering Division under Award No. DE-SC0010596 (P.F.). R.O. would like to acknowledge funding support during his Ph.D. study from Indonesian Endowment Fund for Education-LPDP with the contract No. 202002220216006. Daniel Siderius: Official contribution of the National Institute of Standards and Technology (NIST), not subject to copyright in the United States of America. Daniel Siderius: Certain commercially available items may be identified in this paper. This identification does not imply recommendation by NIST, nor does it imply that it is the best available for the purposes described. B.V.L, S.T.E and A.M.P acknowledge funding from the European Research Council (ERC) under the European Union's Horizon 2020 Research and Innovation Program (Grant agreement no. 639233, COFLeaf)., Porosity and surface area analysis play a prominent role in modern materials science. At the heart of this sits the Brunauer–Emmett–Teller (BET) theory, which has been a remarkably successful contribution to the field of materials science. The BET method was developed in the 1930s for open surfaces but is now the most widely used metric for the estimation of surface areas of microand mesoporous materials. Despite its widespread use, the calculation of BET surface areas causes a spread in reported areas, resulting in reproducibility problems in both academia and industry. To prove this, for this analysis, 18 already-measured raw adsorption isotherms were provided to sixty-one labs, who were asked to calculate the corresponding BET areas. This roundrobin exercise resulted in a wide range of values. Here, the reproducibility of BET area determination from identical isotherms is demonstrated to be a largely ignored issue, raising critical concerns over the reliability of reported BET areas. To solve this major issue, a new computational approach to accurately and systematically determine the BET area of nanoporous materials is developed. The software, called “BET surface identification” (BETSI), expands on the well-known Rouquerol criteria and makes an unambiguous BET area assignment possible., European Research Council (ERC) ERC-2016-COG 726380 ERC-2015-StG 677289 ERC-2017-StG 756489 639233, UK Research & Innovation (UKRI) Innovate UK 104384 UK Research & Innovation (UKRI), Engineering & Physical Sciences Research Council (EPSRC) IAA/RG85685, Cambridge International Scholarship TrinityHenry Barlow Scholarship, United States Department of Energy (DOE) DE-FG02-08ER15967, National Nuclear Security Administration DE-NA-0003525, United States Department of Energy (DOE), Alexander von Humboldt Foundation, Center for Information Services and High Performance Computing (ZIH) at TU Dresden, Department of Science & Technology (India), Science Engineering Research Board (SERB), India CRG/2019/000906, Active Co. Research Grant, European Commission through the H2020-MSCA-RISE-2019 program ZEOBIOCHEM -872102, Spanish MICINN and AEI/FEDER RTI2018-099504-B-C21, University of Alicante UATALENTO17-05, Spanish Government SEV-2017-0706 FWO 12T3519N 11D2220N, UK Research & Innovation (UKRI), Engineering & Physical Sciences Research Council (EPSRC) EP/L015978/1, National Research Foundation of Korea NRF-2017M3A7B4042140 NRF-2017M3A7B4042235, United States Department of Energy (DOE) DE-SC0010596, Indonesian Endowment Fund for Education-LPDP 202002220216006

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.

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.

Photoassisted synthesis is as a highly appealing green procedure for controlled decoration of semiconductor catalysts with co-catalyst nanoparticles, which can be carried out without the concourse of elevated temperatures, external chemical reducing agents or applied bias potential and in a simple slurry reactor. The aim of this study is to evaluate the control that such a photoassisted method can exert on the properties of ruthenium nanoparticles supported on TiO2 by means of the variation of the incident irradiance and hence of the photodeposition rate. For that purpose, different Ru/TiO2 systems with the same metal load have been prepared under varying irradiance and characterized by means of elemental analysis, transmission electron microscopy and X-ray photoelectron spectroscopy. The photocatalytic activity of the so-obtained materials has been evaluated by using the degradation of formic acid in water under UV-A light. Particles with size around or below one nanometer were obtained, depending on the irradiance employed in the synthesis, with narrow size distribution and homogeneous dispersion over the titania support. The relation between neutral and positive oxidation states of ruthenium could also be controlled by the variation of the irradiance. The obtained photocatalytic activities for formic acid oxidation were in all cases higher than that of undecorated titania, with the sample obtained with the lowest irradiation giving rise to the highest oxidation rate. According to the catalysts characterization, photocatalytic activity is influenced by both Ru size and Ru0/Ruδ+ ratio.

[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.

[EN] A series of mixed-metal Fe-III/Ni-II metal-organic frameworks (MOFs) of the MIL-100 type containing different metal ratios have been synthesized de novo, following an approach that requires tuning of the Fe-III/Ni-II reactivity. The resulting heterometallic MIL-100(Fe, Ni) materials maintain thermal, chemical and structural stability with respect to the parent MIL-100(Fe) MOF as can be deduced from various techniques. The nature and the oxidation state of the accessible metal cations have been evaluated by in situ infrared spectroscopy and extended X-ray absorption fine structure measurements. The obtained mixed-metal MOFs and the parent material have been evaluated as heterogeneous catalysts in a model acid-catalyzed reaction, i.e., the Prins reaction. It is found that the catalytic activity improves by more than one order of magnitude upon incorporation of Ni-II, with a complete selectivity for the formation of nopol. This increase in the catalytic activity upon incorporation of Ni-II correlates with the enhancement in the Lewis acidity of the material as determined by CO adsorption. The heterometallic MOF can be recycled without observation of metal leaching, while maintaining the crystal structure under the reaction conditions., This work was supported by the European Commission under the Marie Sklodowska-Curie agreement H2020-MSCA-IF-658224. Measurements at the ROCK synchrotron beamline of SOLEIL were supported by a public grant overseen by the French National Research Agency (ANR) as part of the "Investissements d'Avenir" program (reference: ANR10-EQPX45). H. G. thanks financial support by the Spanish Ministry of Science and Innovation (Severo Ochoa and RTI2018-098237-CO21) and Generalitat Valenciana (Prometeo 2017/083). S. N. thanks financial support by the Fundacion Ramon Areces (XVIII Concurso Nacional para la Adjudicacion de Ayudas a la Investigacion en Ciencias de la Vida y de la Materia, 2016) and Ministerio de Ciencia, Innovacion y Universidades CTQ-2018 RTI2018-099482-A-I00 project.

International audience; Hierarchical porous UiO-66-NH2 cm-monolithic xero- and aero-gels with a controlled shape and mechanical robustness were successfully produced from ethanolic gels. Their remarkable controlled hierarchical porosity was effectively assessed using N2 sorption, Hg intrusion porosimetry and focused ion beam-scanning electron microscopy methods.

International audience; Despite increasing interest in metal–organic frameworks (MOFs) in the biomedical field, developing specific formulations suitable for different administration routes is still a main challenge. Here, we propose a simple, fast and bio-friendly press-molding method for the preparation of cutaneous patches based on composites made from the drug nanocarrier MIL-100(Fe) and biopolymers. The physicochemical properties of the patches (structure, hydration, bioadhesive and swelling properties), as well as their encapsulation and release capabilities (both in ex vitro and ex vivo models), were evaluated using active ingredients such as the challenging cosmetic liporeductor, caffeine, and the model analgesic and anti-inflammatory drug, ibuprofen. In particular, very high caffeine loadings were entrapped within these cutaneous devices with progressive releases under simulated cutaneous physiological conditions as a consequence of the swelling of the hydrophilic patches. Despite the absence of any cutaneous bioadhesive character, these patches provided progressive and suitable permeation of their cosmetic cargo through the skin, interestingly reaching the targeted adipose tissue. This makes these cosmetic-containing composite MOF-based patches promising candidates for new cutaneous devices in cosmetic applications.

Conference Information: 10th International Conference on Petroleum Phase Behavior and Fouling, Rio de Janeiro, Brazil, June 2009; International audience; Ethanol reforming could provide an interesting path for on-board hydrogen production from renewable resources for fuel cell powering. This paper presents a study on hydrogen production from both pure ethanol and E85 with a plasma reactor. Reforming of ethanol was systemically tested with a non-thermal arc discharge system based on a high voltage/low current power source. A short review on ethanol reforming is first presented as a reference point for this study. Effects of supplied power for plasma generation, air/fuel ratio, and addition of water were then experimentally investigated. Those results were at last compared with a 1D multistage model, exhibiting good correlation. In spite of the early stage of research, a fair conversion rate and fair H2 yields have been achieved (90% and 65%, respectively). The optimal conditions for ethanol reforming are found to be at an oxygen ratio higher than the reaction's stoichiometry, with a slight addition of steam. Discussion is provided concerning the non-thermal plasma effect on the ethanol reforming.

International audience; This paper presents a simplified one-dimensional kinetic model (phenomenological approach) of a nonthermal are discharge plasma reactor used for n-octane reforming. After a description of the model and its main assumptions, a parametric analysis of plasma reformer performance addressing the influence of plasma volume, H2O/C ratio, O/C ratio, and input electric power is presented. Results focusing on energy efficiency and conversion rate, including comparison with experimental gasoline reforming data, are analyzed and discussed. The parametric study has provided an optimum for actual plasma reformer, H2O/C = 0, O/C = 1.1, and input electric power between 20 and 25% LHV. The model shows that nonequilibrium chemistry is produced via fast mixing of arc plasma jet and reactants to quench radicals and other active species generated in the high-temperature region.

The biological production of hydrogen, a "clean" energy carrier, has recently aroused a great interest. The most efficient reported micro-organism for hydrogen production from hexose is the anaerobic bacterium Clostridium acetobutylicum with a chemostat production of 2.4 l H2 l-1 h-1, catalyzed by the HydA [FeFe]-hydrogenase. In order to understand and improve C. acetobutylicum hydrogen potentialities, we have attempted to characterize the structure-function relationships of HydA with its redox partners. By homology with the [FeFe]-hydrogenase of Clostridium pasteurianum, the [4Fe- 4S] FS4C and [2Fe-2S] FS2 clusters located on the protein surface were predicted to be involved in the inter-molecular electron transfer between HydA and its redox partners. Our goal was to determine the implication of the FS4C and FS2 clusters in this transfer. To do so, mutagenesis by amino acid substitutions and domain deletions was performed on FS4C and FS2. In order to stabilize native and modified hydrogenases, the purification protocol was improved. Native hydrogenase was successfully stabilized, while the persisting instability of modified hydrogenase was an obstacle of their catalytic characterization. Decreased activity of modified hydrogenases was due to a loss of active site functionality and to a lower iron content than the theoretical value. The physiological redox partners of HydA, ferredoxine CAC0303 and flavodoxin, were purified. The complete catalytic profile of HydA and its kinetic parameter with different redox partners for hydrogen uptake and hydrogen production were determined. The optimized purification protocol led to a significant increase of both hydrogen uptake and hydrogen production activities. We confirmed that the in vitro hydrogen uptake was more favourable than the hydrogen production. A very high kcat was determined with the artificial substrate methyl viologen for the hydrogen uptake activity. This result might indicate that methyl viologen could be prone to interact more or less directly with the active site, shunting the intra-molecular electron transfer chain. High catalytic efficiencies for both H2 uptake and H2 production activities were observed with either artificial (except for reduced methyl viologen) and physiological redox partners. This result reflects the high potential of HydA for hydrogen-related activities which is conserved with three different electron carriers. Hence, in iron-limited growth conditions, the in vivo substitution of ferredoxin by flavodoxin might not be a limitation for in vivo hydrogenase activity.; Source d'énergie renouvelable et non polluante, le biohydrogène connaît un intérêt croissant. En culture continue sur glucose, la productivité d'hydrogène la plus élevée est réalisée par la bactérie anaérobie Clostridium acetobutylicum avec 2,4 litres d'hydrogène produit l-1 h-1. Cette production d'hydrogène est catalysée par la [FeFe]-hydrogénase HydA. Pour comprendre et améliorer les capacités de ce micro-organisme pour la production d'hydrogène, nous avons voulu caractériser les relations structure-fonctions de HydA avec ses partenaires d'oxydo-réduction. Par homologie avec l'hydrogénase à fer I de Clostridium pasteurianum, les centres [4Fe-4S] FS4C et [2Fe-2S] FS2, situés en surface de la protéine, pourraient être impliqués dans le transfert inter-moléculaire d'électrons entre HydA et ses partenaires d'oxydoréduction. Notre objectif a alors été de déterminer l'implication de FS4C et FS2 dans ce transfert. Pour cela, des mutations par substitutions d'acides aminés et par délétions de domaines ont été effectuées au niveau de FS4C et FS2. Pour palier des problèmes d'instabilité des hydrogénases à fer native et modifiées, le protocole de purification a été amélioré. L'hydrogénase native a nettement été stabilisée, mais l'instabilité persistante des hydrogénases modifiées est restée une limitation importante pour leur caractérisation catalytique. La perte d'activité des hydrogénases modifiées a pu être corrélée à une perte importante de fonctionnalité de leur site actif et à un nombre d'atomes de fer incorporés inférieur à la valeur théorique. Les partenaires physiologiques d'oxydo-réduction de HydA chez C. acetobutylicum, la ferrédoxine CAC0303 et la flavodoxine, ont été purifiés. Le profil catalytique complet et les paramètres cinétiques des activités de consommation et de production d'hydrogène de HydA native avec différents partenaires d'oxydo-réduction ont été déterminés. L'amélioration du protocole de purification a permis d'augmenter significativement les activités de consommation et production d'hydrogène. Nous avons confirmé la préférence in vitro de HydA à catalyser la consommation de l'hydrogène par rapport à la production. Une valeur très élevée de kcat a été obtenue avec le substrat artificiel, méthyl viologène, en consommation d'hydrogène. Cela semble indiquer que le méthyl viologène pourrait interagir plus ou moins directement avec le site actif de l'enzyme, en évitant le transfert intramoléculaire d'électrons. Des efficacités catalytiques élevées de consommation et de production de l'hydrogène ont été obtenues avec le méthyl viologène (sauf sous sa forme réduite), la ferrédoxine et la flavodoxine. Ce résultat reflète le haut potentiel de HydA pour les réactions liées à l'hydrogène, potentiel conservé aussi bien pour ses partenaires redox physiologiques qu'artificiel. Ainsi, en condition de croissance en carence en fer, la substitution de la ferrédoxine par la flavodoxine ne serait pas une limitation pour l'activité hydrogénase in vivo.

High-yield syntheses of peculiar carbon nanotubes and carbon 'necklace'-like morphologies have been obtained using a sophisticated thermal plasma technology. This method is based on a thermal plasma, which vapourizes the carbonaceous precursor in the presence of metal catalyst. Electron microscopy analyses provide evidences for a 'stacked-cup' structure for the carbon nanotubes. Carbon nano-'necklaces' are constituted by the repetition of multi-wall carbon spheres, connected along one direction in a 'bell'-like structure, and containing frequently an encapsulated metal particle. Microscopic growth mechanisms are also proposed to interpret both syntheses. Due to their intriguing topology, these new carbon nanotubes and necklaces may find important applications in nano-technology. (C) 2004 Elsevier Ltd. All rights reserved.