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Funding: This work was supported by Faraday Institution (Grant-FIRG018). We are grateful to Engineering and Physical Sciences Research Council (EPSRC) for the Light Element Facility Grant (EP/T019298/1) and Strategic Equipment Resource Grant (EP/R023751/1). Sodium-ion batteries (NIBs) are emerging as promising devices for energy storage applications. Porous solids, such as metal–organic frameworks (MOFs), are well suited as electrode materials for technologies involving bulkier charge carriers. However, only limited progress has been made using pristine MOFs, primarily due to lack of redox-active organic groups in the materials. In this work a azo-functional MOF, namely UiO-abdc, is presented as an electrode compound for sodium-ion insertion. The MOF delivers a stable capacity (∼100 mA h g−1) over 150 cycles, and post-cycling characterisation validates the stability of the MOF and participation of the azo-group in charge storage. This study can accelerate the realisation of pristine solids, such as MOFs and other porous organic compounds, as battery materials. Publisher PDF

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

Authors gratefully thank the following funding sources for financial support: Scottish Enterprise (POC13), EPSRC (EP/K005499/1 and Capital for Great Technologies grant EP/L017008/1), European Social Fund Studentship and the University of St Andrews School of Chemistry. The formulation and antibacterial efficacy of nitric oxide (NO)-releasing MOF–polyurethane films are reported for the first time. Uniform standalone films were successfully prepared containing 1, 5, 10, and 15 wt% CPO-27 (Ni). The MOF within each film was successfully activated and loaded with NO. Adsorption and release profiles are reported for the films and show that while the polymer influences the quantity of NO adsorbed and stored by the MOF and the time scale of release; the proportion of stored NO that is released is dependent on wt% loading of MOF in the film. In a cytotoxicity assay, the formulations exhibited very low toxicity (

The reaction of 1,3-bis(4-carboxyphenyl)-5-ethoxybenzene and copper acetate monohydrate yields copper-1,3-bis(4-carboxyphenyl)-5-ethoxybenzene(DMF), and upon removal of coordinated DMF molecules, copper-1,3-bis(4-carboxyphenyl)-5-ethoxybenzene is attained. The compound does not form as a traditional three-dimensional metal–organic framework and instead produces a “layered coordination framework”, where the individual layers are separated by the ethyl chains on the linker. The synthesis and crystallographic characterization of the material are described.

The rapid growth in the field of metal-organic frameworks (MOFs) over recent years has highlighted their high potential in a variety of applications. For biological and environmental applications MOFs with low toxicity are vitally important to avoid any harmful effects. For this reason, Ca-based MOFs are highly desirable owing to their low cost and high biocompatibility. Useful Ca MOFs are still rare owing to the ionic character and large size of the Ca2+ ion tending to produce dense phases. Presented here is a novel Ca-based MOF containing 2,3-dihyrdoxyterephthalate (2,3-dhtp) linkers Ca(2,3-dhtp)(H2O) (SIMOF-4). The material undergoes a phase transformation on heating, which can be followed by variable temperature powder X-ray diffraction. The structure of the high temperature form was obtained using single-crystal X-ray diffraction. The electrochemical properties of SIMOF-4 were also investigated for use in a Na ion battery.

The authors would like to thank the EPSRC (grants: EP/K025112/1; EP/K005499/1; EP/K503162/1; EP/N509759/1) for funding opportunities. R.E.M., and M.M. would like to acknowledge OP VVV "Excellent Research Teams", project No. CZ.02.1.01/0.0/0.0/15_003/0000417 - CUCAM. We would like to thank the ERC (Advanced Grant 787073 “ADOR”). The hydrolysis (disassembly, D) and rearrangement (organization, O) steps of the assembly-disassembly-organization-reassembly (ADOR) process for the synthesis of zeolites have been studied. Germanium–rich UTL was subjected to hydrolysis conditions in water to understand the effects of temperature (100, 92, 85, 81, 77, and 70 °C). Samples were taken periodically over an 8–37 h period and each sample was analyzed by powder X-ray diffraction. The results show that the hydrolysis step is solely dependent on the presence of liquid water, whereas the rearrangement is dependent on the temperature of the system. The kinetics have been investigated using the Avrami-Erofeev model. With increasing temperature, an increase in rate of reaction for the rearrangement step was observed and the Arrhenius equation was used to ascertain an apparent activation energy for the rearrangement from the kinetic product of the disassembly (IPC-1P) to the thermodynamic product of the rearrangement (IPC-2P). From this information a mechanism for this transformation can be postulated. Publisher PDF

The authors would like to thank the EPSRC (grants: EP/K025112/1; EP/K005499/1; EP/K503162/1; EP/N509759/1) for funding opportunities. R.E.M., J.C. and M.M. would like to acknowledge OP VVV "Excellent Research Teams", project No. CZ.02.1.01/0.0/0.0/15_003/0000417 - CUCAM. S.E.A. would like to thank the Royal Society and the Wolfson Foundation for a merit award. J.C. acknowledges the Czech Science Foundation (P106/12/G015). High-silica zeolites, some of the most important and widely used catalysts in industry, have potential for application across a wide range of traditional and emerging technologies. The many structural topologies of zeolites have a variety of potential uses, so a strong drive to create new zeolites exists. Here, we present a protocol, the assembly–disassembly–organization–reassembly (ADOR) process, for a relatively new method of preparing these important solids. It allows the synthesis of new high-silica zeolites (Si/Al >1,000), whose synthesis is considered infeasible with traditional (solvothermal) methods, offering new topologies that may find novel applications. We show how to identify the optimal conditions (e.g., duration of reaction, temperature, acidity) for ADOR, which is a complex process with different possible outcomes. Following the protocol will allow researchers to identify the different products that are possible from a reaction without recourse to repetitive and time-consuming trial and error. In developing the protocol, germanium-containing UTL zeolites were subjected to hydrolysis conditions using both water and hydrochloric acid as media, which provides an understanding of the effects of temperature and pH on the disassembly (D) and organization (O) steps of the process that define the potential products. Samples were taken from the ongoing reaction periodically over a minimum of 8 h, and each sample was analyzed using powder X-ray diffraction to yield a time course for the reaction at each set of conditions; selected samples were analyzed using transmission electron microscopy and solid-state NMR spectroscopy. Postprint

R.E.M. thanks the Royal Society and the EPSRC (Grants EP/L014475/1, EP/K025112/1) for funding work in this area and the Czech Science Foundation for the project P106/12/G015 and OP VVV “Excellent Research Teams”, project No. CZ.02.1.01/0.0/0.0/15_003/0000417 – CUCAM. SEA thanks the Royal Society/Wolfson Foundation for a merit award, and the European Research Council (EU FP7 Consolidator Grant 614290 “EXONMR”) for funding. This research used resources of the Advanced Light Source, which is a US DOE Office of Science User Facility under contract no. DE-AC02-05CH11231 and the development of the gas cell used in this research was funded through US DOE award # DE-SC0001015. We also thank Diamond Light Source and Chiu Tang for access to beamline I11. We thank Mr Simon Vornholt for help with the electron microscopy and the EPSRC Capital for Great Technologies funding (EP/L017008/1). Highly porous metal–organic frameworks (MOFs), which have undergone exciting developments over the past few decades, show promise for a wide range of applications. However, many studies indicate that they suffer from significant stability issues, especially with respect to their interactions with water, which severely limits their practical potential. Here we demonstrate how the presence of ‘sacrificial’ bonds in the coordination environment of its metal centres (referred to as hemilability) endows a dehydrated copper-based MOF with good hydrolytic stability. On exposure to water, in contrast to the indiscriminate breaking of coordination bonds that typically results in structure degradation, it is non-structural weak interactions between the MOF’s copper paddlewheel clusters that are broken and the framework recovers its as-synthesized, hydrated structure. This MOF retained its structural integrity even after contact with water for one year, whereas HKUST-1, a compositionally similar material that lacks these sacrificial bonds, loses its crystallinity in less than a day under the same conditions. Postprint Postprint

IPC-12 zeolite is the first member of the ADOR family produced by the structural transformation of UOV. The details of the UOV rearrangement were studied to determine the influence of the properties of the parent zeolite and treatment conditions on the outcome of IPC-12 formation. It was established that incomplete disassembly of UOV can be caused by insufficient lability of interlayer connectivity in the parent material possessing Si-enriched D4Rs or by inhibition of hydrolysis by diluted acid at high temperature. The impacts of specific interactions of the framework with anions on controllable breaking of interlayer connectivity and the conditions of the treatment at low pH (

R.E.M. and M.N. thank the Royal Society and the E.P.S.R.C. (Grants EP/L014475/1, EP/K025112/1 and EP/K005499/1) for funding work in this area. R.E.M. and J.Č. acknowledge the Czech Science Foundation for the project P106/12/G015 and OP VVV "Excellent Research Teams", project No. CZ.02.1.01/0.0/0.0/15_003/0000417 - CUCAM. S.E.A. would like to thank the ERC (EU FP7 Consolidator Grant 614290 “EXONMR”) and the Royal Society and Wolfson Foundation for a merit award. The UK 850 MHz solid-state NMR Facility used in this research was funded by EPSRC and BBSRC (contract reference PR140003), as well as the University of Warwick including via part funding through Birmingham Science City Advanced Materials Projects 1 and 2 supported by Advantage West Midlands (AWM) and the European Regional Development Fund (ERDF). W.A.S. and D.S.W. acknowledge the Research Council of Norway and NOTUR are acknowledged for providing the computer time at the Norwegian supercomputer facilities (under the project number NN2875k). The assembly–disassembly–organization–reassembly (ADOR) mechanism is a recent method for preparing inorganic framework materials and, in particular, zeolites. This flexible approach has enabled the synthesis of isoreticular families of zeolites with unprecedented continuous control over porosity, and the design and preparation of materials that would have been difficult—or even impossible—to obtain using traditional hydrothermal techniques. Applying the ADOR process to a parent zeolite with the UTL framework topology, for example, has led to six previously unknown zeolites (named IPC-n, where n = 2, 4, 6, 7, 9 and 10). To realize the full potential of the ADOR method, however, a further understanding of the complex mechanism at play is needed. Here, we probe the disassembly, organization and reassembly steps of the ADOR process through a combination of in situ solid-state NMR spectroscopy and powder X-ray diffraction experiments. We further use the insight gained to explain the formation of the unusual structure of zeolite IPC-6. Postprint

R.E.M. thanks the Royal Society and the Engineering and Physical Sciences Research Council (Grants EP/K025112/1, EP/K005499/1, EP/L016419/1) for funding work in this area and for providing a Ph.D. studentship to S.E.R. through the Criticat Centre for Doctoral training. R.E.M. and M. O. acknowledge the OP VVV "Excellent Research Teams", project No. CZ.02.1.01/0.0/0.0/15_003/0000417 - CUCAM. J.Č., V.K., and M.T. acknowledge the Czech Science Foundation for the project of the Centre of Excellence (P106/12/G015) and J.Č has received funding from the European Union's Horizon2020 research and innovation programme under grant agreement No 640979. The research leading to these results has received funding from the European Union Seventh Framework Programme under Grant Agreement No. 312483—ESTEEM2 (Integrated Infrastructure Initiative–I3). The assembly-disassembly-organization-reassembly (ADOR) process has been used to disassemble a parent zeolite with the UOV structure type and then reassemble the resulting layers into a novel structure, IPC-12. The structure of the material has previously been predicted computationally and confirmed in our experiments using X-ray diffraction and atomic resolution STEM-HAADF electron microscopy. This is the first successful application of the ADOR process to a material with porous layers. Publisher PDF

SEA would like to thank the Leverhulme Trust (F/00 268/BJ) and EPSRC for computational support through the Collaborative Computational Project on NMR Crystallography (CCP-NC), via EP/M022501/1). SEA would also like to thank the Royal Society and Wolfson Foundation for a merit award. MA and RIW would like to acknowledge financial support from the EPSRC (EP/C516591), as would SW (GR/T23824). The research data (and/or materials) supporting this publication can be accessed at DOI: 10.17630/a6d6d27b-a8f0-46cb-8e6b-2c9a344e86b7. We report a study of the CHA-type aluminophosphate AlPO-34, prepared with six different structure-directing agents (SDAs): piperidine (pip), morpholine (mor), pyridine (pyr), 1,4,8,11-tetraazacyclotetradecane (cyclam), 1,3-dimethylimidazolium (dmim) chloride and 1-ethyl-3-methylimidazolium (emim) bromide. Using a combination of solid-state NMR spectroscopy, periodic density functional theory (DFT) calculations and synchrotron X-ray diffraction, we show that, even in crystallographically well-ordered materials such as AlPO-34 with dmim as the SDA, local disorder may be present. For such disordered structures, where it is challenging to use DFT to assign NMR spectra, we show that the 31P isotropic chemical shift can be predicted accurately using the mean P-O bond length and P-O-Al bond angle, in an extension of previous work. Variable-temperature 27Al NMR reveals the presence of microsecond-timescale dynamics in all forms of AlPO-34, with two different motional regimes observed, depending on whether structural H2O is also present. H2O is detected in AlPO-34 prepared with mor as the SDA, although this material was previously reported as anhydrous, suggesting that this form of AlPO-34 may be hygroscopic despite the presence of the SDAs within the pores. Postprint

The authors would like to acknowledge the financial support from the EPSRC industrial CASE award (grant EP/N50936X/1). Here we demonstrate the synthesis and structural characterisation of a novel copper MOF: STAM-NMe2, developed using the linker 5-dimethylamino isophthalic acid. The material is a member of the STAM series of MOFs, with a Kagome lattice structure and contains two types of pore system. The structure was investigated using single crystal X-ray diffraction, variable temperature powder X-ray diffraction was used to determine the thermal stability of the MOF, and nitrogen BET adsorption was employed to determine the porosity of the material. Postprint

L.N.M and R.E.M wish to acknowledge the financial support from the EPSRC industrial CASE award (grant EP/N50936X/1). A.T and G.B would like to thank the financial support from the Fondo per il finanziamento delle attività base di ricerca (grant PJ-RIC-FFABR_2017). Metal-organic frameworks (MOFs) are a class of porous materials that show promise in the removal of Toxic Industrial Chemicals (TICs) from contaminated airstreams, though their development for this application has so far been hindered by issues of water stability and the wide availability and low cost of traditionally used activated carbons. Here a series of three MOF-activated carbon composite materials with different MOF to carbon ratios are prepared by growing STAM-17-OEt crystals inside the commercially available BPL activated carbon. The composite materials display excellent water stability and increased uptake of ammonia gas when compared to unimpregnated carbon. Such properties make these composites very promising in the fields of air purification and personal protective equipment. Postprint

Funding: UK EPSRC EP/K005499/1, EP/K503162, and EP/L017008/1). Single crystal CPO-27-Mg, -Zn and its structural isomer UTSA-74 have been prepared through use of acid modulators; salicylic acid and benzoic acid, respectively. Salicylic acid directed the synthesis of CPO-27-Mg/Zn whereas benzoic acid the synthesis of UTSA-74. Through “in-house” SCXRD, DMF was seen to bind to the Zn2+ and water to the Mg2+ metal sites in CPO-27-M. Although the synthesis conditions were analogous for UTSA-74, DMF is too large to bind due to the proximity of the binding sites. A dissolution–recrystallisation transformation was examined from UTSA-74 to CPO-27-Zn. The release of nitric oxide was measured for each material. Postprint

The structural instability in a humid environment of the majority of metal-organic frameworks (MOFs) is a challenging obstacle for their industrial-scale development. Recently, two water-resistant MOFs have been synthetized, STAM-1 and STAM-17-OEt. They both contain copper paddle wheels, like the well-known water-sensitive HKUST-1, but different organic linkers. The crystal lattice of both the MOFs undergoes a phase transition upon interaction with water molecules. Their unusual flexibility allows the controlled breaking of some interpaddle wheel Cu-O interactions in the so-called crumple zones, with a mechanism called hemilability, which is considered to have a crucial role for the stability toward water. In this work, we present a detailed investigation on the different effects of water exposure on the local and long-range structures of HKUST-1, STAM-1, and STAM-17-OEt. Electron paramagnetic resonance (EPR) spectroscopy has allowed us to characterize the different phases occurring during hydration of each MOF. In particular, we have identified and portrayed the moment of the adsorption of the first water molecule on each copper ion and shown that such soft hydration lead to a similar reversible evolution in all of the three MOFs. This aspect unveiled that the bulk water stability of the MOFs studied is unimportant at this early stage, whereas with a higher degree of hydration (more than few hours in our experimental conditions), we observe the three MOFs embarked on different paths, here carefully described. The evolution of HKUST-1 is not reversible because of its well-known tendency to hydrolysis, but, in contrast, we proved the reversibility of the water effects in STAM-1 and STAM-17-OEt even at the atomic scale level. Furthermore, for the first time, we report a Raman characterization of both STAM-1 and STAM-17-OEt, for each phase of the hydration. The data also include X-ray diffraction, nuclear magnetic resonance measurements, and Brunauer-Emmett-Teller surface area calculations of all the samples.

High-silica zeolites, some of the most important and widely used catalysts in industry, have potential for application across a wide range of traditional and emerging technologies. The many structural topologies of zeolites have a variety of potential uses, so a strong drive to create new zeolites exists. Here, we present a protocol, the assembly-disassembly-organization-reassembly (ADOR) process, for a relatively new method of preparing these important solids. It allows the synthesis of new high-silica zeolites (Si/Al1,000), whose synthesis is considered infeasible with traditional (solvothermal) methods, offering new topologies that may find novel applications. We show how to identify the optimal conditions (e.g., duration of reaction, temperature, acidity) for ADOR, which is a complex process with different possible outcomes. Following the protocol will allow researchers to identify the different products that are possible from a reaction without recourse to repetitive and time-consuming trial and error. In developing the protocol, germanium-containing UTL zeolites were subjected to hydrolysis conditions using both water and hydrochloric acid as media, which provides an understanding of the effects of temperature and pH on the disassembly (D) and organization (O) steps of the process that define the potential products. Samples were taken from the ongoing reaction periodically over a minimum of 8 h, and each sample was analyzed using powder X-ray diffraction to yield a time course for the reaction at each set of conditions; selected samples were analyzed using transmission electron microscopy and solid-state NMR spectroscopy.

The authors would like to thank: The EPSRC (grants: EP/K025112/1; EP/K005499/1; EP/K503162/1) for funding opportunities and beam line I15 at the Diamond Light Source. Phoebe Allan is acknowledged for her help and knowledge of PDF refinement. M.M. and R.E.M. would like to acknowledge OP VVV "Excellent Research Teams", project No. CZ.02.1.01/0.0/0.0/15_003/0000417 - CUCAM. A study into the disassembly and organisation steps of the ADOR process has been undertaken through in situ Pair Distribution Function (PDF) analysis. Three aqueous systems (water, 6 M HCl and 12 M HCl) were introduced to a parent zeolite germanosilicate UTL in a cell. Hydrolysis could be clearly seen when UTL was exposed to water over a period of 8 hr, forming the disorded layered material, IPC-1P. In hydrochloric acid, the hydrolysis step is too quick to observe and a Ge-Cl containing species could be seen. In 6 M HCl, the rearrangement of the interlayer region began after an induction period of 8 hr, with the process still occuring after 15 hr. In 12 M HCl, the rearrangement appears to have come to an end after only 6 hr. Postprint

This work was supported by the EPSRC (Grant No. EP/ K031732/1) and the Royal Society (University Research Fellowship UF150104 to M.D.S.). The data which underpin this work are available at http://dx.doi.org/10.5525/gla. researchdata.590 and are available under a CC-BY licence. The selective and efficient electrocatalytic reduction of nitrite to nitric oxide (NO) is of tremendous importance, both for the development of NO-release systems for biomedical applications and for the removal of nitrogen oxide pollutants from the environment. In nature, this transformation is mediated by (among others) enzymes known as the copper-containing nitrite reductases. The development of synthetic copper complexes that can reduce nitrite to NO has therefore attracted considerable interest. However, there are no studies describing the crucial role of proton-coupled electron transfer during nitrite reduction when such synthetic complexes are used. Herein, we describe the synthesis and characterization of two previously unreported Cu complexes ( 3 and 4 ) for the electrocatalytic reduction of nitrite to NO, in which the role of proton-relaying units in the secondary coordination sphere of the metal can be probed. Complex 4 bears a pendant carboxylate group in close proximity to the copper center, while complex 3 lacks such functionality. Our results suggest that complex 4 is twice as effective an electrocatalyst for nitrite reduction than is complex 3 and that complex 4 is the best copper-based molecular electrocatalyst for this reaction yet discovered. The differences in reactivity between 3 and 4 are probed using a range of electrochemical, spectroscopic, and computational methods, which shed light on the possible catalytic mechanism of 4 and implicate the proton-relaying ability of its pendant carboxylate group in the enhanced reactivity that this complex displays. These results highlight the critical role of proton-coupled electron transfer in the reduction of nitrite to NO and have important implications for the design of biomimetic catalysts for the selective interconversions of the nitrogen oxides. Publisher PDF

M.M., P.S.W., G.P.M.B., S.E.A., and R.E.M. thank the EPSRC (grants: EP/K025112/1, EP/L014475/1, and EP/ M506631/1) for funding. M.M., P.N., J.Č. and R.E.M. would like to acknowledge OP VVV "Excellent Research Teams", project No. CZ.02.1.01/0.0/0.0/15_003/0000417 - CUCAM. J.Č. and P.N. acknowledge the Czech Science Foundation (P106/12/G015) for the financial support of this research. J.P.A. acknowledges EPSRC support for the high pressure work. ADOR, an unconventional synthesis strategy based on a four-step mechanism: assembly, disassembly, organization, and reassembly, has opened new possibilities in zeolite chemistry. The ADOR approach led to the discovery of the IPC family of materials with tuneable porosity. Here we present the first pressure-induced ADOR transformation of 2D zeolite precursor IPC-1P into fully crystalline 3D zeolite IPC-2 (OKO topology) using a Walker-type multianvil apparatus under a pressure of 1 GPa at 200 °C. Surprisingly, the high-pressure material is of lower density (higher porosity) than the product obtained from simply calcining the IPC-1P precursor at high temperature, which produces IPC-4 (PCR topology). The sample was characterized by PXRD, 29Si MAS NMR, SEM, and HRTEM. Theoretical calculations suggest that high pressure can lead to the preparation of other ADOR zeolites that have not yet been prepared. Postprint Postprint

The unique features of the germanosilicate zeolite possessing the UTL framework topology offer various post-synthetic modifications such as ‘top-down’, ‘inverse sigma’ or solid-state transformations. The presented work describes several different synthetic routes generating the IPC-2 type zeolite (OKO topology) utilizing UTL as the parent material. In total, five approaches were investigated which exhibit this topological transformation from germanosilicate UTL to OKO type material: (1) alkoxysilylation of the layered precursor (IPC-1P) formed by hydrolysis of UTL; (2) direct conversion of UTL by treatment in 7–12 M hydrochloric acid; (3) direct transformation under mild conditions of water and ammonium nitrate solution on Al- and B-UTL; (4) repeated calcinations of boron-containing UTL; (5) using organic solutions as self-stabilization agents. Resulting materials were examined by powder XRD, nitrogen sorption, SEM and EDX. Briefly, all the materials possessed the same OKO topology but had differing BET surface areas and micropore volumes in the ranges of 201–493 m 2 /g and 0.095–0.189 cm 3 /g, respectively. The morphologies of crystals were very similar, while the size of them varied between 10 and 50 μm. The main goal of the study was to emphasize the complexity of post-synthetic UTL zeolite chemistry and the diverse range of solid-state transformations possible.

This research was supported through the Center for Gas Separations Relevant to Clean Energy Technologies, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under award DE-SC0001015. We thank Arkema and Gerald K. Branch for fellowship support of E.D.B. and Ateneo Project 2011 ORTO11RRT5 for financial support of S.B., C.L., and S.C. C.L. acknowledges the Mega-grant of the Russian Federation Government number 14.Y26.31.0001 for support. An iron(II)-based metal–organic framework featuring coordinatively unsaturated redox-active metal cation sites, Fe2(dobdc) (dobdc4– = 2,5-dioxido-1,4-benzenedicarboxylate), is shown to strongly bind nitric oxide at 298 K. Adsorption isotherms indicate an adsorption capacity greater than 16 wt %, corresponding to the adsorption of one NO molecule per iron center. Infrared, UV–vis, and Mössbauer spectroscopies, together with magnetic susceptibility data, confirm the strong binding is a result of electron transfer from the FeII sites to form FeIII–NO– adducts. Consistent with these results, powder neutron diffraction experiments indicate that NO is bound to the iron centers of the framework with an Fe–NO separation of 1.77(1) Å and an Fe–N–O angle of 150.9(5)°. The nitric oxide-containing material, Fe2(NO)2(dobdc), steadily releases bound NO under humid conditions over the course of more than 10 days, suggesting it, and potential future iron(II)-based metal–organic frameworks, are good candidates for certain biomedical applications. Postprint

The authors thank the EPSRC (EP/K025112/1) for funding work in this area. R.E.M., J.Č. and P.N. acknowledge the Czech Science Foundation for the project P106/12/G015 and OP VVV “Excellent Research Teams”, project No. CZ.02.1.01/0.0/0.0/15_003/0000417 – CUCAM. The research data supporting this publication can be accessed at DOI: http://dx.doi.org/10.17630/9691c5a8-b456-4c1a-98a1-af66791311d5. The hydrothermal synthesis of a zeolite with properties suitable for use in the assembly–disassembly–organization–reassembly (ADOR) process was designed, and a zeolite called SAZ-1 was successfully prepared. This zeolite was then used as a parent in the ADOR process, and two new daughter zeolites, IPC-15 and IPC-16, were prepared. The X-ray powder diffraction patterns of the new zeolites match well with those predicted using computational methods. The three materials form an isoreticular series with decreasing pores size from 14-ring to 12-ring to 10-ring. Postprint Postprint

Funding: Royal Society for provision of an industry fellowship and the EPSRC for funding (EP/K025112/1 and EP/L014475/1) (R.E.M.); Czech Science Foundation for (P106/12/G015) (J.Cˇ.); European Community under a Marie Curie Intra-European Fellowship (A.B.P.). Zeolites are important materials whose utility in industry depends on the nature of their porous structure. Control over microporosity is therefore a vitally important target. Unfortunately, traditional methods for controlling porosity, in particular the use of organic structure-directing agents, are relatively coarse and provide almost no opportunity to tune the porosity as required. Here we show how zeolites with a continuously tuneable surface area and micropore volume over a wide range can be prepared. This means that a particular surface area or micropore volume can be precisely tuned. The range of porosity we can target covers the whole range of useful zeolite porosity: from small pores consisting of 8-rings all the way to extra-large pores consisting of 14-rings. Publisher PDF

The properties of zeolites, and thus their suitability for different applications, are intimately connected with their structures. Synthesizing specific architectures is therefore important, but has remained challenging. Here we report a top-down strategy that involves the disassembly of a parent zeolite, UTL, and its reassembly into two zeolites with targeted topologies, IPC-2 and IPC-4. The three zeolites are closely related as they adopt the same layered structure, and they differ only in how the layers are connected. Choosing different linkers gives rise to different pore sizes, enabling the synthesis of materials with predetermined pore architectures. The structures of the resulting zeolites were characterized by interpreting the X-ray powder-diffraction patterns through models using computational methods; IPC-2 exhibits orthogonal 12- and ten-ring channels, and IPC-4 is a more complex zeolite that comprises orthogonal ten- and eight-ring channels. We describe how this method enables the preparation of functional materials and discuss its potential for targeting other new zeolites. Postprint

International audience; Adsorption and release of the biologically active nitric oxide (NO) was evaluated over a series of highly flexible iron(III) dicarboxylate MOFs of the MIL-88 structure type, bearing fumaric or terephthalic spacer functionalized or not by polar groups (NO2. 2OH). As evidenced by ex situ X-ray powder diffraction and in situ IR spectroscopy, it appears that if the contracted dried forms of MIL-88 do not expand their structures in the presence of NO, the combination of very narrow pores and trimers of iron polyhedra leads to the adsorption of significant amounts of NO either physisorbed (very narrow pores) and/or chemisorbed [iron(II) or iron(III) coordinatively unsaturated metal sites (CUS)]. The delivery of NO under vapor of water or in simulated body fluid does not exceed 20% range of the total adsorbed amount probably due to a partial release that occurs between the adsorption/desorption setup and the chemiluminescence release tests. Some of these solids nevertheless exhibit a significant release at the biological levels over a long period of time (\textgreater16 h) that make these biocompatible and biodegradable MOFs of interest for the controlled release of NO.

The Authors would like to thank: The EPSRC (grant EP/K025112/1) and the Czech Science Foundation grant no. P106/12/G015 (Centre of Excellence) for funding opportunities and beam lines I15 and I11 at the Diamond Light Source. Nicola Casati and Antonio Cervelino from the MS Powder beamline at the Swiss Light Source are acknowledged for their support in the data collection. A.B.P. acknowledges the support of the European Community under a Marie Curie Intra-European Fellowship for Career Development. The disordered intermediate of the ADORable zeolite UTL has been structurally confirmed using the pair distribution function (PDF) technique. The intermediate, IPC-1P, is a disordered layered compound formed by the hydrolysis of UTL in 0.1M hydrochloric acid solution. Its structure is unsolveable by traditional X-ray diffraction techniques. The PDF technique was first benchmarked against high-quality synchrotron Rietveld refinements of IPC-2 (OKO) and IPC-4 (PCR) – two end products of IPC-1P condensation that share very similar structural features. An IPC-1P starting model derived from density functional theory was used for the PDF refinement, which yielded a final fit of Rw = 18% and a geometrically reasonable structure. This confirms the layers do stay intact throughout the ADOR process and shows PDF is a viable technique for layered zeolite structure determination. Postprint

R.E.M. thanks the Royal Society and the E.P.S.R.C. (Grants EP/L014475/1, EP/K025112/1 and EP/K005499/1) for funding work in this area. J.Č. acknowledges the Czech Science Foundation for the project of the Centre of Excellence (P106/12/G015) and the European Union Seventh Framework Programme (FP7/ 2007-‐‐2013) under grant agreement n°604307. Zeolites are an important class of materials that have wide ranging applications such as heterogeneous catalysts and adsorbents which are dependent on their framework topology. For new applications or improvements to existing ones, new zeolites with novel pore systems are desirable. We demonstrate a method for the synthesis of novel zeolites using the ADOR route. ADOR is an acronym for Assembly, Disassembly, Organization and Reassembly. This synthetic route takes advantage of the assembly of a relatively poorly stable zeolite which can be selectively disassembled into a layered material. The resulting layered intermediate can then be organized in different manners by careful chemical manipulation and then reassembled into zeolites with new topologies. By carefully controlling the organization step of the synthetic pathway, new zeolites with never before seen topologies are capable of being synthesized. The structures of these new zeolites are confirmed using powder X-ray diffraction and further characterized by nitrogen adsorption and scanning electron microscopy. This new synthetic pathway for zeolites demonstrates its capability to produce novel frameworks that have never been prepared by traditional zeolite synthesis techniques. Publisher PDF

A novel methodology, called ADOR (assembly–disassembly–organisation–reassembly), for the synthesis of zeolites is reviewed here in detail. The ADOR mechanism stems from the fact that certain chemical weakness against a stimulus may be present in a zeolite framework, which can then be utilized for the preparation of new solids through successive manipulation of the material. In this review, we discuss the critical factors of germanosilicate zeolites required for application of the ADOR protocol and describe the mechanism of hydrolysis, organisation and condensation to form new zeolites starting from zeolite UTL. Last but not least, we discuss the potential of this methodology to form other zeolites and the prospects for future investigations.

Nitric oxide (NO) is important for the regulation of a number of diverse biological processes, including vascular tone, neurotransmission, inflammatory cell responsiveness, defence against invading pathogens and wound healing. Transition metal exchanged zeolites are nanoporous materials with high-capacity storage properties for gases such as NO. The NO stores are liberated upon contact with aqueous environments, thereby making them ideal candidates for use in biological and clinical settings. Here, we demonstrate the NO release capacity and powerful bactericidal properties of a novel NO-storing Zn 2+ -exchanged zeolite material at a 50 wt.% composition in a polytetrafluoroethylene polymer. Further to our published data showing the anti-thrombotic effects of a similar NO-loaded zeolite, this study demonstrates the anti-bacterial properties of NO-releasing zeolites against clinically relevant strains of bacteria, namely Gram-negative Pseudomonas aeruginosa and Gram-positive methicillin-sensitive and methicillin-resistant Staphylococcus aureus and Clostridium difficile . Thus our study highlights the potential of NO-loaded zeolites as biocompatible medical device coatings with anti-infective properties.

Metal organic frameworks (MOFs) are highly porous materials that can store significant amounts of gas, including nitric oxide. The chemical composition and toxicology of many (but not all) of these materials makes them potentially suitable for medical applications. In this paper, we will describe how triggered release methods can be used to deliver biologically relevant amounts of NO and then show how Ni, Co and Cu-containing MOFs are biologically active materials with potential applications in several different areas (anti-thrombosis, dermatology and wound healing, anti-bacterial, vasodilation etc.). We will also discuss the pros and cons of MOFs, including their chemical and biological stability and the toxicology of MOFs in general.

For medical purposes, materials are required that store and target specifically deliver exogenous nitric oxide (NO). Partially zinc-exchanged Na-LTA (Linde type A) zeolite (Zn-LTA) has high potential in this respect due to its non-toxicity and adsorption capacity for NO. In contrast to NO adsorbed to LTA zeolites prepared for catalytic purposes, lower dehydration temperature prior to NO adsorption is used to achieve a balance between production cost and high activity. In order to study the interaction of NO with the metal sites in the samples prepared under these medical conditions, continuous-wave X-band electron paramagnetic resonance has been applied. In contrast to Na-LTA with only one weakly interacting NO monomer, three different monomers, having stronger interaction to the metal sites than in Na-LTA, were observed in Zn-LTA. To improve the storage capacity of Zn-LTA, higher dehydration temperatures would be necessary.

Two porous metal organic frameworks (MOFs), [M2(C8H2O6)(H2O)2] x 8 H2O (M = Co, Ni), perform exceptionally well for the adsorption, storage, and water-triggered delivery of the biologically important gas nitric oxide. Adsorption and powder X-ray diffraction studies indicate that each coordinatively unsaturated metal atom in the structure coordinates to one NO molecule. All of the stored gas is available for delivery even after the material has been stored for several months. The combination of extremely high adsorption capacity (approximately 7 mmol of NO/g of MOF) and good storage stability is ideal for the preparation of NO storage solids. However, most important is that the entire reservoir of stored gas is recoverable on contact with a simple trigger (moisture). The activity of the NO storage materials is proved in myography experiments showing that the NO-releasing MOFs cause relaxation of porcine arterial tissue.

R.E.M. thanks the Royal Society and the E.P.S.R.C. (Grants EP/L014475/1, EP/K025112/1 and EP/K005499/1) for funding work in this area. J.Č. and P.N. acknowledge the Czech Science Foundation for the project of the Centre of Excellence (P106/12/G015) and the European Union Seventh Framework Programme (FP7/ 2007-­‐2013) under grant agreement n°604307. The research leading to these results has received funding from the European Union Seventh Framework Programme under Grant Agreement 312483 – ESTEEM2 (Integrated Infrastructure Initiative–I3). We thank Professor Wuzong Zhou and Dr. Fengjiao Yu for their expertise in TEM and Daniel Dawson for help with NMR. Zeolites are porous aluminosilicate materials that have found applications in many different technologies. However, although simulations suggest that there are millions of possible zeolite topologies, only a little over 200 zeolite frameworks of all compositions are currently known, of which about 50 are pure silica materials. This is known as the zeolite conundrum - why have only so few of all the possible structures been made? Several criteria have been formulated to explain why most zeolites are unfeasible synthesis targets. Here we demonstrate the synthesis of two such 'unfeasible' zeolites, IPC-9 and IPC-10, through the assembly-disassembly-organization-reassembly mechanism. These new high-silica zeolites have rare characteristics, such as windows that comprise odd-membered rings. Their synthesis opens up the possibility of preparing other zeolites that have not been accessible by traditional solvothermal synthetic methods. We envisage that these findings may lead to a step change in the number and types of zeolites available for future applications. Postprint

REM is a Royal Society Industry Fellow and thanks the Royal Society for the provision of the Brian Mercer Award for Innovation, and thanks Scottish Enterprise for support. REM also thanks the British Heart Foundation for a New Horizons Award (NH/11/8/29253). REM and TD thank the EPSRC for funding (EP/K025112/1 and EP/K005499/1). The highly porous nature of metal-organic frameworks (MOFs) offers great potential for the delivery of therapeutic agents. Here, we show that highly porous metal-organic frameworks can be used to deliver multiple therapeutic agents—a biologically active gas, an antibiotic drug molecule, and an active metal ion—simultaneously but at different rates. The possibilities offered by delivery of multiple agents with different mechanisms of action and, in particular, variable timescales may allow new therapy approaches. Here, we show that the loaded MOFs are highly active against various strains of bacteria. Publisher PDF

The structure determination of as-made silica zeolites CHA and FER prepared in the presence of fluoride ions has been accomplished using microcrystal X-ray diffraction at a synchrotron source. In both cases, the location of the fluoride ions has been determined. Fluoride ions are incorporated into small double six-ring cages in the CHA framework, and the organic guests have been located in the larger chabazite cages. In contrast to two previous single-crystal X-ray diffraction studies of as-made siliceous FER prepared in related ways fluoride ions are incorporated into the framework and are found occluded inside small cages in the structure.

Two aluminofluorophosphates have been synthesized using 1,4,8,11-tetraazacyclotetradecane (cyclam) as a structure-directing agent (SDA). The two materials were synthesized hydrothermally and their structures solved by microcrystal diffraction using synchrotron radiation. In both cases, the SDA has been located crystallographically. The first material, [F, Cyclam]-AlPO-CHA, has the molecular formula Al6P6O24F2.C10N4H26 and has a framework structure related to the mineral chabazite, with the cyclam molecules occluded within chabazite-like cages (space group P–1, a=9.0993(4) A, b=9.2232(5) A, c=9.3929(4) A, α=77.881(2)o, β=87.205(1)o, γ=87.777(1)o, Z=1, wR(F2)=0.1354, R(F)=0.0487). The second material, [F, Cu-Cyclam]-AlPO-SAS, has the molecular formula Al8P8O32F2.[CuC10N4H24.2H2O] and has a framework structure closely related to STA-6 (SAS) zeolite structure type, although the usual tetragonal symmetry has been reduced to monoclinic by the presence of the fluoride ions (space group P21/n, a=10.3738(4) A, b=14.8060(5) A, c=13.4494(5) A, β=90.275(1)o, Z=2, wR(F2)=0.1484, R(F)=0.0524). The cyclam is occluded as a copper complex ordered within the cages of the structure.

A layered aluminofluorophosphate and a cobalt–aluminophosphate material have been prepared using the azamacrocycle meso-5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane (Tet-A) as a structure-directing agent (SDA). Both were synthesised using hydrothermal techniques and their structures solved using microcrystal X-ray diffraction. The first material, [F, Tet-A]-AlPO-1, has the molecular formula Al10P10O40F2C16N4H38 and crystallises in the orthorhombic space group Pca21. Its inorganic layered structure is related to the AlPO-41 (AFO) zeolite structure type. The second material, [Co, Tet-A]-AlPO-2, has the formula Al4(PO4)4(HPO4)2·[Co(C16N4H36)]·C16N4H38·2H2O and crystallises in the triclinic space group P. This material contains a cobalt–Tet-A complex that is covalently bound to the inorganic framework and an uncoordinated Tet-A molecule that is hydrogen bonded to the framework.

A new aluminium 3-aminopropylphosphonate sulfate hydrate has been prepared using hydrothermal methods, and its structure solved using microcrystal X-ray diffraction at a synchrotron source. The structure consists of one-dimensional chains of aluminium 3-aminopropylphosphonate with sulfate anions occluded between the chains. It is unusual in compounds of this type to have anionic groups between positively charged aluminium phosphonate units. Further characterisation of the compound has been carried out using magic angle spinning NMR.

The structure of Ni-2(dobdc) (dobdc(4) = 2,5-dioxido-1,4-benzenedicarboxylate) as a function of deuterium adsorption has been determined through the application of in situ neutron powder diffraction. Detailed information concerning the local adsorption potential for hydrogen at each site has also been probed using inelastic neutron scattering techniques. These results are compared to those previously published on isostructural analogs and the Ni2+ variant shows the shortest deuterium-metal distance in the M-2(dobdc) series (M = Mg, Zn, Co, Fe) that have been studied so far. Postprint

The title compound is a salt, bis(4,4'-bipyridyl-4,4'-diium) bis[3,4-dihydroxy-3-cyclobutene-1,2-dionate(1-)] 3,4-dihydroxy-3-cyclobutene-1,2-dionate(2-), 2C 10 H 10 N 2 2+ .2C 4 HO 4 - .C 4 O 4 2- . The cations and the (C 4 O 4 ) 2- anions are linked by two types of short N-H…O hydrogen bond [N...O 2.595 (2) and 2.622 (2) A; NH...O 167 and 170°] to form a planar rectangular net built from a single type of centrosymmetric R 8 6 (56) ring. The (C 4 HO 4 ) - anions are linked by paired short OH…O hydrogen bonds [O…O 2.471 (2) A and O-H...O 152°] into centrosymmetric dimers containing an R 2 2 (10) motif. A [(C 4 HO 4 ) - ] 2 dimer lies at the centre of each R 8 6 (56) ring, and is linked to it by two C-H...O hydrogen bonds [C…O 3.318 (3) and 3.165 (3) A; C-H…O 155 and 151°].

The title compound, piperazine-1,4-diium 3,4-dihydroxy-3-cyclobutene-1,2-dionate(2-) dihydrate, is a hydrated salt, C 4 H 12 N 2 2+ .C 4 O 4 2- .2H 2 O. The water molecules and the centrosymmetric anions are linked by O-H...O hydrogen bonds into two-dimensional nets built from a single type of R 8 6 (24) ring. Adjacent nets are linked by the centrosymmetric cations, each of which forms four N-H...O hydrogen bonds, with four different anions as acceptors.

In the 2:3 adduct of 3,5-dihydroxybenzoic acid and 4,4'-bipyridine, 2C 7 H 6 O 4 .3C 10 H 8 N 2 , the two components are linked by six independent O-H...N hydrogen bonds [O...N 2.685 (3)-2.814 (3) A and O-H...N 170-178°] into a C 4 4 (32)[R 4 4 (30)] chain of rings. Each chain is linked to two neighbouring chains by means of aromatic π...π stacking interactions.

The 1:1 adduct of 5-hydroxyisophthalic acid and 4,4'-trimethylenedipyridine is a salt, [HNC 5 H 4 (CH 2 ) 3 C 5 H 4 N] + .[HOC 6 H 3 (COOH)COO] - (C 13 H 15 N 2 + .C 8 H 5 O 5 - ). The anions are linked into C(7) chains by means of O-H...O hydrogen bonds [O...O 2.734 (2) A and O-H...O 176°], and these chains are linked by the cations via O-H...N and N-H...O hydrogen bonds [O...N 2.620 (2) A, O-H...N 175°, N...O 2.748 (2) A and N-H...O 176°] into four identical but independent interpenetrating three-dimensional frameworks.