Dissecting quasars with the J-PAS narrow-band photometric survey

Nuclear Activity in Galaxies Across Cosmic Time, Proceedings of the conference held 7-11 October 2019 in Addis Ababa, Ethiopia. Edited by Mirjana Pović et al. Proceedings of the International Astronomical Union, Volume 356, pp. 12-16The J-PAS survey will soon start observing thousands of square degrees of the Northern Sky with its unique set of 56 narrow band filters covering the entire optical wavelength range, providing, effectively, a low resolution spectra for every object detected. Active galaxies and quasars, thanks to their strong emission lines, can be easily identified and characterized with J-PAS data. A variety of studies can be performed, from IFU-like analysis of local AGN, to clustering of high-z quasars. We also expect to be able to extract intrinsic physical quasar properties from the J-PAS pseudo-spectra, including continuum slope and emission line luminosities. Here we show the first attempts of using the QSFit software package to derive the properties for 22 quasars at 0.8 < z < 2 observed by the miniJPAS survey, the first deg2 of J-PAS data obtained with an interim camera. Results are compared with the ones obtained by applying the same software to SDSS quasar spectra.Financial support from the State Agency for Research of the Spanish MCIU through the "Center of Excellence Severo Ochoa" award to the Instituto de Astrofísica de Andalucía (SEV-2017-0709

Co@NH 2

We present a synthetic strategy for the efficient encapsulation of a deriv. of a well-​defined cobaloxime proton redn. catalyst within a photoresponsive metal-​org. framework (NH2- MIL-​125(Ti)​)​. The resulting hybrid system Co@MOF is demonstrated to be a robust heterogeneous composite material. Furthermore, Co@MOF is an efficient and fully recyclable noble metal-​free catalyst system for light-​driven hydrogen evolution from water under visible light illumination

Engineering of Metal Organic Framework Catalysts

The last few decades have witnessed the unprecedented explosion of a new research field built around Metal-Organic Frameworks (MOFs). MOFs are crystalline porous solids consisting of metal ions (also named clusters) coordinated to often rigid organic molecules (also called ligands) to form one- two-, or three- dimensional structures. This combination of organic and inorganic building blocks into highly ordered, crystalline structures offers an almost infinite number of combinations, enormous flexibility in pore size, shape and structure, and plenty of opportunities for facile tuning by functionalization, grafting and/or encapsulation. This field has rapidly evolved from an early stage, in which the main scope was the discovery of new structures, to a more mature stage in which dozens of applications are currently being explored like gas storage, separation, sensing or drug delivery. Last but not least, its tunable morphology, pore size, and adsorption properties, along with its intrinsic hybrid nature, all point at MOFs as very promising heterogeneous catalyst. This dissertation describes the development of a new generation of hybrid catalysts based on Metal-Organic Frameworks decorated with active functionalities and the study of its implementation into challenging catalytic processes. Metal clusters with unsaturated sites, organic functionalities and encapsulation of macromolecules or nanoparticles in the pores of these tunable crystalline structures are among the methods investigated in this dissertation. This work investigates from the design of the catalysts to the final application: from the molecular to the reactor scale. The research presents a deep insight in successful methodologies for future multifunctional systems and the catalytic performance of such active sites when confined into highly ordered structures, supported by extensive characterization.Chemical Engineering / Catalysis EngineeringApplied Science

Metal-organic framework capillary microreactor for application in click chemistry

A Cu/PMA–MIL-101(Cr) metal–organic-framework-coated microreactor has been applied in the 1,3-dipolar cycloaddition of benzyl azide and phenylactetylene (click chemistry). The Cu/PMA–MIL-101(Cr) catalyst was incorporated by using a washcoating method. The use of tetraethylorthosilicate (TEOS) and a copolymer pluronic F127 as binders resulted in a stable and uniform coating of 6 μm. The application of the Cu/PMA–MIL-101(Cr) capillary microreactor in the click-chemistry reaction resulted in a similar intrinsic activity as in the batch reactor, and a continuous production for more than 150 h time-on-stream could be achieved. The presence of water in the reagent feed led to reversible catalyst deactivation and was necessary to be removed to obtain a stable catalyst operation

Highly dispersed platinum in metal organic framework NH2-MIL-101(Al) containing phosphotungstic acid - Characterization and catalytic performance

The synthesis, characterization (FT-IR, XPS, NMR, UV–Vis), and catalytic performance of Pt supported on phosphotungstic acid (PTA) encapsulated in a metal organic framework (MOF) are reported. The highly dispersed Keggin units of PTA in NH2-MIL-101(Al), synthesized in one step, act as anchoring sites for the Pt precursor species. After different post-treatments, the resulting catalysts have been tested in the oxidation of CO, the preferential oxidation of CO in the presence of H2, and the hydrogenation of toluene. Reduction at 473 K results in the formation of small Pt0 clusters and Pt^2+ species. Reduction at 573 K induces the formation of intermetallic Pt–W^5+ species, which exhibit the best CO oxidation activity and a higher selectivity toward CO2 than alumina supported Pt, resembling the combination of a noble metal on a reducible support. In toluene hydrogenation, the MOF catalysts perform worse than Pt on alumina, ascribed to the too small size of the Pt clusters in the MOF catalysts

Highly dispersed platinum in metal organic framework NH2-MIL-101(Al) containing phosphotungstic acid - Characterization and catalytic performance

The synthesis, characterization (FT-IR, XPS, NMR, UV–Vis), and catalytic performance of Pt supported on phosphotungstic acid (PTA) encapsulated in a metal organic framework (MOF) are reported. The highly dispersed Keggin units of PTA in NH2-MIL-101(Al), synthesized in one step, act as anchoring sites for the Pt precursor species. After different post-treatments, the resulting catalysts have been tested in the oxidation of CO, the preferential oxidation of CO in the presence of H2, and the hydrogenation of toluene. Reduction at 473 K results in the formation of small Pt0 clusters and Pt^2+ species. Reduction at 573 K induces the formation of intermetallic Pt–W^5+ species, which exhibit the best CO oxidation activity and a higher selectivity toward CO2 than alumina supported Pt, resembling the combination of a noble metal on a reducible support. In toluene hydrogenation, the MOF catalysts perform worse than Pt on alumina, ascribed to the too small size of the Pt clusters in the MOF catalysts

Towards acid MOFs – catalytic performance of sulfonic acid functionalized architectures

In this work, the inclusion of free sulfonic acid groups in highly stable MOFs is explored. The synthesized catalysts have been applied in a model esterification reaction. Two metal organic frameworks bearing sulfonic acid moieties are investigated: HSO3-MIL-101(Cr) synthesized following different approaches and a new structure based on HSO3-bdc and Zr. The acidic properties, catalytic performance, deactivation and stability of the different structures are critically evaluated. In the case of MIL-101(Cr), deactivation of the sulfonic groups via formation of butanol sulfonic esters has been observed. Due to the strong interaction between –SO3 _ and the Cr open metal site where usually fluorine (F_) is located in the structure, the HSO3-MIL-101(Cr) catalysts are not stable under acidic regeneration conditions. When using Zr as a metal node, a new and stable sulfonic acid containing porous structure was synthesized. This structure showed high activity and full re-usability in the esterification of n-butanol with acetic acid. In this case, deactivation of the catalyst due to sulfonic ester formation could be reversed by reactivation under acidic conditions.Chemical EngineeringApplied Science