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[Display omitted] • Avelino Corma's group at the Instituto de Catálisis y Peroleoquímica, the seed of the Instituto de Tecnología Química (ITQ). • The beginnings of ITQ in Valencia, creating a way of doing science. • From the laboratory to the industry, some ITQ success stories. • Basic science applied to solve real industrial problems, one of the founding pillars of ITQ. • The ITQ, a multidisciplinary approach to research in the field of zeolites. [ABSTRACT FROM AUTHOR]

A combined experimental and computational study has been applied in order to understand the effect of the addition of subsequent methyl groups to chiral (1R,2S)-(−)-ephedrine on its structure-directing behavior during crystallization of the nanoporous AFI aluminophosphate. Results show that bare ephedrine and the double-methylated N,N-dimethyl-ephedrinium display the most efficient structure-directing abilities, while the mono-methylated derivative shows a poor structure-directing capacity towards this framework. Fluorescence spectroscopy indicates that confinement of the mono- and di-methylated derivatives within the nanopores of the AFI channels involves a preferential incorporation of the SDA molecules as monomers. In contrast, occlusion of the bare ephedrine can lead to a strong supramolecular aggregation, depending on the synthesis conditions. Molecular simulations suggest that the stronger trend of ephedrine to form supramolecular aggregates when confined within the AFI channels is due to the formation of two intermolecular H-bonds between consecutive molecules in the dimers interface, which balances the strong electrostatic repulsion between closely-located positive charges of the N atoms under this supramolecular arrangement. The addition of subsequent methyl groups reduces the possibility of establishing these interdimer H-bond interactions that stabilize dimers while provoking steric repulsions, thus reducing the supramolecular aggregation. [ABSTRACT FROM AUTHOR]

In an attempt to promote chirality in AFI-based materials through spatial distributions of dopants, a systematic variation of the synthesis conditions of Mg-doped aluminophosphate-based microporous materials using chiral (1R,2S)-ephedrine as structure-directing agent has been carried out in order to understand the supramolecular chemistry and packing arrangements of these molecules when confined within the AFI channels. The formation of ephedrine dimers is strongly dependent on the synthesis conditions, especially the ephedrine/H 2 O ratio (higher concentrations of ephedrine favour the incorporation of dimers), crystallisation temperature (higher temperatures enhance the supramolecular aggregation) and Mg content (lower Mg contents increase the formation of dimers). The latter influence is explained by molecular simulations in terms of an electrostatic repulsion between the ammonium groups of closely-located adjacent dimers when a high density of protonated ephedrine molecules is required in order to compensate for the high Mg incorporation. In this situation, dimers are only incorporated if the system is forced by increasing the concentration of ephedrine in the gel and increasing the temperature. Our results show that a similar number of ephedrine molecules and Mg dopants are incorporated in the AFI unit cell because of charge-balancing purposes, suggesting a strong electrostatic interaction between both species with opposite charge. [ABSTRACT FROM AUTHOR]

Highlights: [•] TAPO-5 materials with different Ti(III) sources and content has been prepared. [•] TAPO-5 promotes the cyclohexene oxidation through allylic mechanism. [•] Ti(III)APO-5 is more active than the conventional Ti(IV)APO-5. [•] The activity per Ti center of Ti(III)APO-5 materials exponentially increases by decreasing Ti content. [Copyright &y& Elsevier]

The influence of addition of amines (hexylamine, tripropylamine, dodecylamine, and hexadecylamine) and dopants (Zr, Ce) on the properties of mesostructured aluminas (MAs) synthesized using either Tergitol 15-S-9 or Triton X-114 surfactants was investigated. Selected MAs were evaluated as supports for Co and Ru-Co catalysts and their Fischer-Tropsch synthesis (FTS) performance assessed at 493 K, 2.0 MPa, and H 2 /CO = 2. The materials were characterized by XRD, N 2 sorption, TG-DTG, EA, XPS, H 2 -TPR, H 2 chemisorption, and STEM. Regardless of the surfactant, all amines enlarged the pore size of undoped MAs by ca. 2–3 nm. The impact of amines on BET area and pore volume depended, however, on the surfactant-amine combination and on the presence and concentration of dopants. The Ru-promoted catalyst supported on the MA synthesized with Tergitol-tripropylamine doped with Zr displayed the highest FTS activity and C 5+ selectivity due to both high cobalt reducibility and optimum particle size (8 nm). Unlabelled Image • Mesoporous aluminas (MAs) prepared with non-ionic surfactants and different amines. • Effect of doping MAs with Zr or Ce depends on surfactant-amine combination. • Doping with Zr raises the activity of Co/Al 2 O 3 for Fischer-Tropsch synthesis (FTS). • Adding Ru further enhances the FTS activity and C 5+ selectivity of Co/Zr-Al 2 O 3. [ABSTRACT FROM AUTHOR]

A new synthetic smectite-like vanadosilicate, named Vanadosilicate Araraquara Madrid (VAM), containing V3+ was prepared by a hydrothermal method and its behavior as catalyst for methanol oxidation was investigated by X-ray Absorption Spectroscopy (XAS) under operando conditions. The samples were characterized by powder X-ray Diffraction (XRD), Scanning and Transmission Electronic Microscopy (SEM and TEM), CHN chemical analysis, as well as Nuclear Magnetic Resonance spectroscopy, Ultraviolet–visible spectroscopy (UV–Vis) and XAS. The use of VCl 3 as a source of vanadium in low oxidation state (V3+) together with a mixture of hexamethyleneimine (HMI) and N,N,N -trimethyl-1-adamantamonium hydroxide (TMAdaOH) and the preparation of the synthesis mixture under inert atmosphere are mandatory for an efficient formation of this smectite-like vanadosilicate. XRD analyses show the synthetic smectite-like vanadosilicate to be impurity free and dioctahedral smectite peaks were observed. TEM observations together with EDS analyses indicate that the chemical composition is consistent with the dioctahedral structure. XAS measurements have revealed that six-coordinated vanadium is present on VAM, in an environmental similar to that reported for roscoelite mineral. The catalytic properties of this material were evaluated during methanol transformation under operando conditions. The reaction mechanism under different atmospheres was investigated and the results indicated that the process under He leads to the formation of H 2 and CO, while the presence of oxygen shifts the mechanism toward the partial oxidation of methanol. Unlabelled Image • New synthetic vanadosilicate (VAM) was obtained from a mixture of suitable templates. • Low oxidation state vanadium (V3+) was incorporated in framework. • VAM materials could be promising catalyst for oxidation reactions. [ABSTRACT FROM AUTHOR]

Styryl dyes are generally poor fluorescent molecules inherited from their flexible molecular structures. However, their emissive properties can be boosted by restricting their molecular motions. A tight confinement into inorganic molecular sieves is a good strategy to yield highly fluorescent hybrid systems. In this work, we compare the confinement effect of two Mg-aluminophosphate zeotypes with distinct pore systems (the AEL framework, a one-dimensional channeled structure with elliptical pores of 6.5 Å × 4.0 Å, and the CHA framework, composed of large cavities of 6.7 Å × 10.0 Å connected by eight-ring narrower windows) for the encapsulation of 4-DASPI styryl dye (trans-4-[4-(Dimethylamino)styryl]-1-methylpyridinium iodide). The resultant hybrid systems display significantly improved photophysical features compared to 4-DASPI in solution as a result of tight confinement in both host inorganic frameworks. Molecular simulations reveal a tighter confinement of 4-DASPI in the elliptical channels of AEL, explaining its excellent photophysical properties. On the other hand, a singular arrangement of 4-DASPI dye is found when confined within the cavity-based CHA framework, where the 4-DASPI molecule spans along two adjacent cavities, with each aromatic ring sitting on these adjacent cavities and the polymethine chain residing within the narrower eight-ring window. However, despite the singularity of this host-guest arrangement, it provides less tight confinement for 4-DASPI than AEL, resulting in a slightly lower quantum yield.

The combination between photoactive molecules and inorganic structures is of great interest for the development of advanced materials in the field of optics. Particularly, zeotypes with extra-large pore size are attractive because they allow the encapsulation of bulky dyes. The microporous aluminophoshate Mg-ITQ-51 (IFO-type structure) represents an ideal candidate because of the synergic combination of two crucial features: the IFO framework itself, which is composed of non-interconnected one-dimensional extra-large elliptical channels with a diameter up to 11 Å able to host bulky guest species, and the particular organic structure-directing agent used for the synthesis (1,8-bis(dimethylamino)naphthalene, DMAN), which efficiently fills the IFO pores, and is itself a photoactive molecule with interesting fluorescence properties in the blue range of the visible spectrum, thus providing a densely-incorporated donor species for FRET processes. Besides, occlusion of DMAN dye in the framework triggers a notable improvement of its fluorescence properties by confinement effect. To extend the action of the material and to mimic processes such as photosynthesis in which FRET is essential, two robust laser dyes with bulky size, rhodamine 123 and Nile Blue, have been encapsulated for the first time in a zeolitic framework, together with DMAN, in a straightforward one-pot synthesis. Thus, photoactive systems with emission in the entire visible range have been achieved due to a partial FRET between organic chromophores protected in a rigid aluminophosphate matrix.

In an attempt to promote the crystallization of chiral inorganic frameworks, we explore the ability of chiral (1R,2S)-ephedrine and its diastereoisomer (1S,2S)-pseudoephedrine to act as organic building blocks for the crystallization of hybrid organo-inorganic aluminophosphate frameworks in the presence of fluoride. These molecules were selected because of their particular molecular asymmetric structure, which enables a rich supramolecular chemistry and a potential chiral recognition phenomenon during crystallization. Up to four new low-dimensional materials have been produced, wherein the organic molecules form an organic bilayer in-between the inorganic networks. We analyze by molecular simulations the trend of these chiral molecules to form these types of framework, which is directly related to their amphiphilic nature that triggers a strong self-assembly through hydrophobic interactions between aromatic rings and hydrophilic interactions with the fluoro-aluminophosphate inorganic units. Such a self-assembly process is strongly dependent on the concentration of the organic molecules.

A cyanine dye (PIC) was occluded into two 1D-nanopoporus Mg-containing aluminophosphates with different pore size (MgAPO-5 and MgAPO-36 with AFI and ATS zeolitic structure types, with cylindrical channels of 7.3 Å diameter and elliptical channels of 6.7 Å × 7.5 Å, respectively) by crystallization inclusion method. Different J-aggregates are photophysically characterized as a consequence of the different pore size of the MgAPO frameworks, with emission bands at 565 nm and at 610 nm in MgAPO-5 and MgAPO-36, respectively. Computational results indicate a more linear geometry of the J-aggregates inside the nanochannels of the MgAPO-36 sample than those in MgAPO-5, which is as a consequence of the more constrained environment in the former. For the same reason, the fluorescence of the PIC monomers at 550 nm is also activated within the MgAPO-36 channels. Owing to the strategic distribution of the fluorescent PIC species in MgAPO-36 crystals (monomers at one edge and J-aggregates with intriguing emission properties at the other edge) an efficient and one-directional antenna system is obtained. The unidirectional energy transfer process from monomers to J-aggregates is demonstrated by remote excitation experiments along tens of microns of distance., Competing Interests: The authors declare no competing financial interest.

The private book collection of David Lindsay, First Lord Lindsay of Balcarres (1587-1641), was one of the largest in early modern Scotland. Despite being dispersed during the following three centuries, this collection still provides evidence for Lindsay's scientific interests and approach to the study of alchemy. In this paper we seek to partially reconstruct his library by describing and, where possible, identifying the sources of Lindsay's own transcriptions of alchemical texts, as well as works mentioned in a book-list written in his hand. We conclude that Lindsay was not just an important early modern collector, but also a careful reader, part of an extensive network of contacts with whom he exchanged books and information.

Proper combination of template and optimized reaction conditions provides zeolite FER with homogeneous distribution of Al in the framework; this results in a new zeolite adsorbent exhibiting a constant heat of CO(2) adsorption.

A combination of experimental characterisation techniques and computational modelling has allowed us to gain insight into the molecular features governing structure direction in the synthesis of microporous aluminophosphates. The occlusion of three different structure-directing agents (SDAs), triethylamine (TEA), benzylpyrrolidine (BP) and (S)-(-)-N-benzylpyrrolidine-2-methanol (BPM), within the AFI structure during its crystallisation, together with the simultaneous incorporation of water, has been experimentally measured. We found a higher incorporation of organic molecules in the structure obtained with BPM, while a higher water (and lower organic) content is found for the ones obtained with TEA and BP as SDAs. The computational study provides a thermodynamic explanation for the observed behaviour in terms of the relative stabilisation energy of the SDAs and water molecules within the AFI framework compared with when they are in aqueous solution, and demonstrates that a competition for preferential occupation exists between water and organic SDAs, which is a function of the interaction with the inorganic framework. The lower interaction of TEA and BP molecules with the AFI structure promotes the simultaneous incorporation of water molecules in the 12-membered-ring (MR) channel, to increase the host-guest interaction energy and thus the thermodynamic stability. The presence of strongly interacting methanol groups in the BPM molecules leads to the incorporation of only organic molecules within the 12-MR channels. Our results demonstrate the essential role that water molecules play in the stabilisation of hydrophilic microporous aluminophosphates; a minimum amount of organic SDA is, however, essential for a templating role of the microporous architecture.