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The understanding of the structural framework and metal locations within zeolites are two critical aspects to tune and further exploit their properties as heterogeneous catalysts, advanced optical devices, or as water remediation materials. The development of electron microscopy has made it possible to observe directly the zeolitic framework and the distribution of extra framework cations within the pores at the atomic level. Here, we have studied the EMT framework providing data with an unprecedented spatial resolution, which have allowed the analysis of the FAU domains present in the framework. Additionally, potassium and lead (introduced by aqueous ion exchange), which were nonperiodically distributed in the pores have been located. An alternative image mode, annular bright field, has been used, proving its usefulness to extend the spatial resolution and increase the sensitivity toward light elements such as bridging oxygen. Finally, the combination of atomic imaging (local information) with the three-dimensional electron diffraction tomography analysis (averaged information) determined the lead-EMT crystal symmetry to be P63mc. ; The authors would like to thank the Centre for High-resolution Electron Microscopy (CℏEM), supported by SPST of ShanghaiTech University under contract No. EM02161943 and the National Natural Science Foundation of China NFSC-21850410448 and NSFC- 21835002. A.M. also acknowledges the Spanish Ministry of Science through the Ramon y Cajal Program (RYC2018-024561-I) and the regional government of Aragon (Spain) (DGA E13_20R). This project has received funding from the European Union's Horizon 2020 research and innovation program under grant agreement no. 823717—ESTEEM3. ; Peer reviewed

Special Issue: Advanced Microscopy and Spectroscopy for Catalysis . ; Metal-organic frameworks (MOFs) are a family of porous solids combining organic and inorganic moieties with tunable porosity. Their structural parameters have converted MOFs into suitable compounds for gas storage or drug delivery. However, despite the excellent crystallinity they tend to exhibit their analysis through transmission electron microscopy is extraordinarily complicated owing to the high instability under the electron beam irradiation. In here, high-resolution Cs-corrected STEM imaging was used for the observation of the building units of MIL-100(Fe), and special attention was paid to the electron beam current. In addition, MIL-100(Fe) was reacted with AgNO3 through a solid-state reaction technique, which resulted into the formation of metal nanoparticles on the surface. The incorporation of Ag into the porous network has been also investigated. ; AM acknowledges the Government of Aragon and the European Social Fund under the project grant number E/26 "Construyendo Europa desde Aragón" 2014–2020. This work has been partially financed by the Spanish State Research Agency (Agencia Española de Investigación, AEI) and the European Regional Development Fund (Fondo Europeo de Desarrollo Regional, FEDER) through Project MAT2016-77496-R (AEI/FEDER, UE). ; Peer reviewed

© 2014 American Chemical Society ; This paper describes the preparation and characterization of nanoscaled M-MOF-74/CPO-27-M (M = Mg, Mn, Co, Ni, and Zn) materials at room temperature. Some of the so-formed crystals are the smallest ones of any metal−organic framework (MOF) material (and, to the best of our knowledge, of any microporous material) ever reported. They are at the limit of being able to diffract, particularly those forming the Co- and Ni-MOF-74 samples. Consequently, unequivocal identification as the crystalline MOF-74 phase was deduced by combining other characterization techniques rather than powder X-ray diffraction. These small crystals are unstable as isolated ones, so they form steady and robust aggregates, whose mechanical properties strongly depend on the crystal size. The particles that result from the "fusion" of nanocrystals smaller than 10 nm (more properly denoted as nanodomains) could not be disaggregated by conventional ultrasonic and graining techniques. On the contrary, agglomerates of crystals larger than 10 nm are dissociable in discrete crystals. It allows characterizing Zn-MOF-74 nanocrystals by advanced electron microscopy methods. Cs-corrected scanning transmission electron microscopy (STEM) provided, for the first time, "quasi" atomic resolution images of MOFs, which are especially unstable under electronic radiation. The magnitude of the crystal size of M-MOF-74 is tentatively associated with the solubility of the metal source. ; Funding is from Spanish Ministry (MAT-2012−31127) and European Union Seventh Framework Programme under Grant Agreement 312483 - ESTEEM2 (Integrated Infrastructure Initiative-I3). ; Peer Reviewed

Stacking faults are two-dimensional planar defects frequently arising in zeolites, modifying their properties and potentially affecting their performance in catalysis and separation applications. In classical zeolite intergrowths, a topologically unique zeolite layer may often pile up after some spatial transformation (lateral translation, rotation, and/or reflection) that may occur in different amounts or directions with about similar probabilities, leading to a difficult to control disorder. Here, we present a new kind of zeolite intergrowth that requires an additional topologically distinct layer rather than a spatial transformation of a unique one. Stacking of the so-called pentasil layers produces the well-known medium pore zeolite MFI. Intercalation in strict alternation of a topologically distinct second layer sandwiched between pentasil layers expands the structure to produce the new extra-large pore IDM-1. Stacking disorder modulates the structural expansion along the stacking direction. The disordered materials have been studied by simulation of the X-ray diffraction patterns using the program DIFFaX and by Cs-corrected highresolution electron microscopy. We show that disorder does not occur at random but in extended domains and can be controlled all the way from MFI to IDM-1 by just varying the concentration of the synthesis mixture. ; The authors thank funding from the Spanish Ministry of Science, Innovation and Universities, under Projects MAT2015-71117-R (MINECO/FEDER, UE), PID2019-105479RB-I00 and RTI2018-101599-B-C22 (MCUI/AEI/FEDER, UE), the Swedish Research Council (VR), and the Knut and Alice Wallenberg Foundation (KAW). L.A.V. also thanks the Generalitat Valenciana (project PROMETEO/2018/024). A.M. acknowledges the Spanish Ministry of Science (RYC2018-024561-I) and the Regional government of Aragon (DGA E13_20R), the National Natural Science Foundation of China (NFSC-21850410448 and NSFC-21835002), and the Centre for High-resolution Electron Microscopy (CℏEM), supported by SPST of ShanghaiTech University under contract No. EM02161943. ; Peer reviewed

The real industrial establishment of metal–organic frameworks (MOFs) requires significant advances in economic and chemical sustainability. This work describes a novel and simple method to prepare one of the most widely studied MOF materials, i.e., MIL-100(Fe), which significantly improves the sustainability of the conventional process in several aspects. This MOF material is prepared (i) at room temperature (instead of 150 °C used in the conventional method), (ii) after a few hours (instead of 6 days), (iii) in the absence of any inorganic corrosive acid (significant amounts of HF and HNO3 are used in the conventional method), and (iv) it is washed at room temperature (unlike the washing at 80 °C for 3 h). Interestingly, the only difference in the preparation method of MIL-100(Fe) compared with that of semiamorphous Fe-BTC (MOF material commercialized as Basolite F300 having the same metal and linker, and which can be also prepared under similar sustainable conditions) is to start from Fe(II) or Fe(III) sources, respectively, which opens certain versatility options in the room temperature synthesis procedures of MOF materials. The prepared samples were characterized using X-ray diffraction, thermogravimetric analysis, N2 adsorption/desorption isotherms, Cs-aberration corrected scanning transmission electron microscopy, and UV–vis diffuse reflectance spectroscopy. These two room-temperature-made Fe-BTC materials were tested in the industrially demanded photocatalytic degradation of methyl orange under both ultraviolet and solar light radiation. MIL-100(Fe) was a very active photocatalyst in comparison with its homologue. That difference was mainly attributed to the presence of larger cavities within its structure. ; A.M. acknowledges European Union Seventh Framework Programme under Grant Agreement 312483 - ESTEEM2 (Integrated Infrastructure Initiative-I3). C.A.D.C. acknowledges Science without Borders - CNPq - Brazil. K.G. and I.D. also acknowledge CSIC for Development Program I-COOP-2014 COOPB20082 project number. This work has been (partially) financed by the Spanish State Research Agency (Agencia Española de Investigación, AEI) and the European Regional Development Fund (Fondo Europeo de Desarrollo Regional, FEDER) through Project MAT2016-77496-R (AEI/FEDER, UE). ; Peer reviewed

Herein, gas phase synthesis and characterization of multifunctional core@shell, Au@TiOx nanoparticles have been reported. The nanoparticles were produced via a one-step process using a multiple-ion cluster source under a controlled environment that guaranteed the purity of the nanoparticles. The growth of the Au cores (6 nm diameter) is stopped when they pass through the Ti plasma where they are covered by an ultra-thin (1 nm thick) and homogeneous titanium shell that is oxidized in-flight before the soft-landing of the nanoparticles. The Au cores were found to be highly crystalline with icosahedral (44%) and decahedral (66%) structures, whereas the shell, mainly composed of TiO2 (79%), was not ordered. The highly electrical insulating behaviour of the titanium oxide shell was confirmed by the charging effect produced during X-ray photoemission spectroscopy. ; This work was supported by the European ERC-2013-SyG 610256 NANOCOSMOS and European Union Seventh Framework Programme under grant agreement no. 604391 FET Graphene Flagship and by the Spanish Ministerio de Ciencia e Innovación under projects no. MAT2014-59772-C2-2-P and MAT2016-80394-R. A. M. acknowledges the Government of Aragon and the European Social Fund under the project grant number E/26 "Construyendo Europa desde Aragón" 2014–2020. ; Peer reviewed

The synthesis of nano-sized ZIF-11 with an average size of 36 ± 6 nm is reported. This material has been named nano-zeolitic imidazolate framework-11 (nZIF-11). It has the same chemical composition and thermal stability and analogous H2 and CO2 adsorption properties to the conventional microcrystalline ZIF-11 (i.e. 1.9 ± 0.9 μm). nZIF-11 has been obtained following the centrifugation route, typically used for solid separation, as a fast new technique (pioneering for MOFs) for obtaining nanomaterials where the temperature, time and rotation speed can easily be controlled. Compared to the traditional synthesis consisting of stirring + separation, the reaction time was lowered from several hours to a few minutes when using this centrifugation synthesis technique. Employing the same reaction time (2, 5 or 10 min), micro-sized ZIF-11 was obtained using the traditional synthesis while nano-scale ZIF-11 was achieved only by using centrifugation synthesis. The small particle size obtained for nZIF-11 allowed the use of the wet MOF sample as a colloidal suspension stable in chloroform. This helped to prepare mixed matrix membranes (MMMs) by direct addition of the membrane polymer (polyimide Matrimid®) to the colloidal suspension, avoiding particle agglomeration resulting from drying. The MMMs were tested for H2/CO2 separation, improving the pure polymer membrane performance, with permeation values of 95.9 Barrer of H2 and a H2/CO2 separation selectivity of 4.4 at 35 °C. When measured at 200 °C, these values increased to 535 Barrer and 9.1. ; Financial support from the Spanish MINECO (MAT2013-40566-R, CTQ2012-31762, and RyC-2009-03913), the Aragón Government and the ESF is gratefully acknowledged. In addition, research leading to these results has received funding from the European Union Seventh Framework Programme (FP7/2007–2013) under grant agreement no. 608490, project M4CO2. Finally, the use of the Servicio General de Apoyo a la Investigación-SAI (Universidad de Zaragoza) is acknowledged.

This article belongs to the Special Issue Multifunctional Magnetic Nanocomposites: Innovative Processing and Applications. ; Magnetic nanoparticles (NP), such as magnetite, have been the subject of research for application in the biomedical field, especially in Magnetic Hyperthermia Therapy (MHT), a promising technique for cancer therapy. NP are often coated with different compounds such as natural or synthetic polymers to protect them from oxidation and enhance their colloidal electrostatic stability while maintaining their thermal efficiency. In this work, the synthesis and characterization of magnetite nanoparticles coated with fucoidan, a biopolymer with recognized biocompatibility and antitumoral activity, is reported. The potential application of NP in MHT was evaluated through the assessment of Specific Loss Power (SLP) under an electromagnetic field amplitude of 14.7 kA m−1 and at 276 kHz. For fucoidan-coated NP, it was obtained SLP values of 100 and 156 W/g, corresponding to an Intrinsic Loss Power (ILP) of 1.7 and 2.6 nHm2kg−1, respectively. These values are, in general, higher than the ones reported in the literature for non-coated magnetite NP or coated with other polymers. Furthermore, in vitro assays showed that fucoidan and fucoidan-coated NP are biocompatible. The particle size (between ca. 6 to 12 nm), heating efficiency, and biocompatibility of fucoidan-coated magnetite NP meet the required criteria for MHT application. ; This work was developed within the scope of the project CICECO-Aveiro Institute of Materials, UIDB/50011/2020 & UIDP/50011/2020, financed by national funds through the Portuguese Foundation for Science and Technology/MCTES. The work was also funded through FCT projects PTDC/NAN-MAT/28785/2017 (OrMagNa), UID/MULTI/04046/2019 (BioISI) and UIDP/50017/2020 & UIDB/50017/2020 (CESAM). This work was also funded by national funds (OE), through FCT—Fundação para a Ciência e a Tecnologia, I.P., in the scope of the framework contract foreseen in the numbers 4, 5 and 6 of the article 23, of the Decree-Law 57/2016, of August 29, changed by Law 57/2017, of July 19. The Portuguese Foundation for Science and Technology (FCT) is also acknowledged for the research contract under Stimulus of Scientific Employment of P. Ferreira (IF/00300/2015) and H. Oliveira (CEECIND/04050/2017), the Post-Doctoral grant of C. Nunes (SFRH/BPD/100627/2014), and the research contract of V. Bastos (CDL-CTTRI-161-ARH/2018) funded by the FCT project (POCI-01-0145-FEDER-031794). AM acknowledges the Spanish Ministry of Science (RYC2018-024561-I) and to the Natural National Science Foundation of China through the grants NSFC- 21850410448 & NSFC- 21835002. The authors acknowledge to The Centre for High-resolution Electron Microscopy (CħEM), supported by SPST of ShanghaiTech University under contract No. EM02161943. This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 823717—ESTEEM3. ; Peer reviewed

The use of hydrogen as an energy vector leads to the development of materials with high hydrogen adsorption capacity. In this work, a new layered stannosilicate, UZAR-S3, is synthesized and delaminated, producing UZAR-S4. UZAR-S3, with the empirical formula Na4SnSi5O14·3.5H2O and lamellar morphology, is a layered stannosilicate built from SnO6 and SiO4 polyhedra. The delamination process used here comprises three stages: protonation with acetic acid, swelling with nonylamine and the delamination itself with an HCl/H2O/ethanol solution. UZAR-S4 is composed of sheets a few nanometers thick with a high aspect ratio and a surface area of 236 m2/g, twenty times higher than that of UZAR-S3. At −196 °C for UZAR-S4, H2 adsorption reached remarkable values of 3.7 and 4.2 wt% for 10 and 40 bar, respectively, the latter value giving a high volumetric H2 storage capacity of 26.2 g of H2/L. ; Financial support from the Spanish Ministerio de Economía y Competitividad (MINECO) is gratefully acknowledged through projects with grant numbers: MAT2010-15870, CTQ2012-31229 and CTQ2012-31762, as well as from the Fondo Europeo de Desarrollo Regional (FEDER), Regional Government of Aragón (DGA) and the European Social Fund (ESF). A. Berenguer-Murcia and C. Casado-Coterillo thank the MINECO for Ramón y Cajal fellowships (RyC 2009-03913 at the University of Alicante and RYC-2011-08550 at the University of Cantabria).

Liquid-Assisted Pulsed Laser Ablation (LA-PLA) is a promising top-down method to directly synthesize colloidal dispersions of nanoparticles in a eco-friendly manner. However, the role of LA-PLA synthesis parameters is not yet fully agreed. This work seeks to optimize the production of nanoscale zero-valent iron (nZVI) particles suitable for biomedical or environmental applications using nanosecond LA-PLA on iron targets with different ablation media, laser and target scanning parameters. The use of alcohols as solvents produces iron-iron oxide core-shell nanoparticles with amorphous cores, except for a small crystalline fraction corresponding to the biggest core sizes. Decreasing carbon chain length and complexity leads to a thinning of the carbonaceous material coatings and an increase of the colloidal stability and the nanoparticle productivity. Moreover, a decrease of solvent density and surface tension allows obtaining reduced sizes and polydispersity values. Among, laser and scanning parameters, the pulse accumulation per spot displayed a clear effect in boosting size and productivity. As main outcome, aqueous dispersions with suitable colloidal properties are obtained, either by transferring to water of optimized nZVI particles produced in ethanol, or by direct formation of nZVI particles and in situ coating with hydrophilic molecules in aqueous solutions of these molecules ; This research has been funded by the Spanish Ministry of Economy and Competitiveness (MINECO) and FEDER [research projects MAT2015-67354R, MAT2014-53961-R, and MAT2017- 86826-R] and by the Aragón government (DGA) [grant for consolidated group PLATON E31_17R]. OBM thanks the financial support from the "Ramón y Cajal Program" [research project RYC2010-07332] of the Spanish Ministry of Economy and Competitiveness (MINECO) and the H2020 Action H2020-MSCA-IF-2014_ST [grant 656908-NIMBLIS] of the Executive Agency for Research Manages of EU Commission

Nanostructured silver (Ag) and gold (Au) are widely known to be potent biocidal and cytotoxic agents as well as biocompatible nanomaterials. It has been recently reported that combining both metals in a specific chemical composition causes a significant enhancement in their antibacterial activity against antibiotic-resistant bacterial strains, as well as in their anticancer effects, while preserving cytocompatibility properties. In this work, Ag/Au bimetallic nanoparticles over a complete atomic chemical composition range were prepared at 10 at% through a green, highly reproducible, and simple approach using starch as a unique reducing and capping agent. The noble metal nanosystems were thoroughly characterized by different analytical techniques, including UV-visible and FT-IR spectroscopies, XRD, TEM/EDS, XPS and ICP-MS. Moreover, absorption spectra simulations for representative colloidal Ag/Au-NP samples were conducted using FDTD modelling. The antibacterial properties of the bimetallic nanoparticles were determined against multidrug-resistant Escherichia coli and methicillin-resistant Staphylococcus aureus, showing a clear dose-dependent inhibition even at the lowest concentration tested (5 µg/mL). Cytocompatibility assays showed a medium range of toxicity at low and intermediate concentrations (5 and 10 µg/mL), while triggering an anticancer behavior, even at the lowest concentration tested, in a process involving reactive oxygen species production per the nanoparticle Au:Ag ratio. In this manner, this study provides promising evidence that the presently fabricated Ag/Au-NPs should be further studied for a wide range of antibacterial and anticancer applications. ; The groups at CSIC and Tecnologico de Monterrey acknowledge the i-Link+2019 program (ref. LINKB20024 "NANOBIO-ROJA") for financial support. AM acknowledges the Spanish Ministry of Science (RYC2018-024561-I), the regional government of Aragon (E13_20R), the European Union's Horizon 2020 research and innovation programme (823717– ESTEEM3) and the National Natural Science Foundation of China (NSFC- 21835002). ; Peer reviewed

8 pags, 4 figs. -- The online version contains supplementary material available at https://doi.org/10.1038/s41467-021-26184-0 ; Development of sustainable processes for hydrocarbons synthesis is a fundamental challenge in chemistry since these are of unquestionable importance for the production of many essential synthetic chemicals, materials and carbon-based fuels. Current industrial processes rely on non-abundant metal catalysts, temperatures of hundreds of Celsius and pressures of tens of bars. We propose an alternative gas phase process under mild reaction conditions using only atomic carbon, molecular hydrogen and an inert carrier gas. We demonstrate that the presence of CH2 and H radicals leads to efficient C-C chain growth, producing micron-length fibres of unbranched alkanes with an average length distribution between C23-C33. Ab-initio calculations uncover a thermodynamically favourable methylene coupling process on the surface of carbonaceous nanoparticles, which is kinematically facilitated by a trap-and-release mechanism of the reactants and nanoparticles that is confirmed by a steady incompressible flow simulation. This work could lead to future alternative sustainable synthetic routes to critical alkane-based chemicals or fuels. ; We thank Jose Criado for the artwork schematics of the system, in figures 4 and S1; Funding: We thank the European Research Council for funding support under Synergy grant ERC-2013-SyG, G.A. 610256 (NANOCOSMOS). Also, we acknowledge partial support from the Spanish MINECO through grants PID2020-113142RB-C21, PID2019106315RB-I00, and PID2019-106315RB-I00, EU ERC CoG HyMAP 648319, and from the regional government through project S2018-NMT-4367 (FotoArt-CM). AM acknowledges to the Spanish Ministry of Science (RYC2018-024561-I), to the Regional Government of Aragon (DGA E13_20R), to the National Natural Science Foundation of China (NFSC-21850410448, NSFC-21835002), and to the The Centre for Highresolution Electron Microscopy (ChEM), supported by SPST of ShanghaiTech University under contract No. EM02161943. S.K. and G.H. acknowledge funding from the Turbulent Superstructures Program of the German National Science Foundation (DFG) ; Peer reviewed