catena-Poly[[[aqua­(formato-κO)(1,10-phenanthroline-κ2 N,N′)manganese(II)]-μ-formato-κ2 O:O′] monohydrate]

The title compound, {[Mn(HCOO)2(C12H8N2)(H2O)]·H2O}n, consists of polymeric chains of the complex [Mn(HCOO)2(phen)(H2O)]∞ (phen is 1,10-phenanthroline) with solvent water mol­ecules. The chains contain six-coordinate MnII ions bridged by formate anions. They are further extended into a three-dimensional network via O—H⋯O hydrogen-bonding inter­actions and inter­chain π–π stacking inter­actions, with a centroid–centroid distance of 3.679 (4) Å

Hollow Y zeolite single crystals: synthesis, characterization and activity in the hydroisomerization of n-hexadecane

International audienceHollow Y zeolite single crystals have been obtained from a conventional NaY zeolite following a three-step process involving a severe dealumination of the zeolite with silicon tetrachloride (step #1), followed by an acid washing under mild conditions (step #2) and finally a selective dissolution of the crystals core in the presence of protective Al species (step #3). Crystals are characterized by the presence of a regular internal cavity with 0.1–0.2 nm thick microporous walls. They contain a relatively low framework Al content but significant amounts of extraframework Al oxide species mainly located on the external surface of the crystals. Hollow crystals have been mixed with a Pt-supported alumina binder and used as catalysts in the hydroisomerization of n-hexadecane. Compared to the corresponding bulk crystals obtained after step #2, their higher activity has been attributed to a better efficiency, directly resulting from the presence of the cavity

Tests for the Use of La2Mo2O9-based Oxides as Multipurpose SOFC Core Materials

International audienceThe mixed ionic-electronic conductivity under dilute hydrogen, the stability and the catalytic activity under propane:air type mixtures of a series of LAMOX oxide-ion conductors have been studied. The effect of exposure to dilute hydrogen on the conductivity of the -La2(Mo2 - yWy)O9 series at 600 °C depends on tungsten content: almost negligible for the highest (y = 1.4), it is important for La2Mo2O9 (y = 0). In propane:air, all tested LAMOX electrolytes are stable at 600-700 °C, but get reduced when water vapour is present. La2Mo2O9 is the best oxidation catalyst of the series, with an activity comparable to that of nickel.The catalytic activity of other tested LAMOX compounds is much lower, (La1.9Y0.1)Mo2O9 showing a deactivation phenomenon. These results suggest that depending on composition, La2(Mo2 - yWy)O9 compounds could be either electrolytes in single-chamber SOFC and dual-chamber micro-SOFC (y = 1.4) or anode materials in dual-chamber SOFC (low y) or oxidation catalysts in SOFCs operating with propane (y = 0)

Facile synthesis of an ultramicroporous MOF tubular membrane with selectivity towards CO(2)

International audienceA substituted imidazolate-based MOF (SIM-1) membrane has been crystallized in situ on a tubular asymmetric alumina support that can be exploited for gas separation through preferential adsorption

Systematic study of the impact of MOF densification into tablets on textural and mechanical properties

Four different metal-organic framework powders (UiO-66, UiO-66-NH, UiO-67, and HKUST-1) were shaped into tablets. The effect of the applied pressure on porous properties, mechanical resistance and tablet bulk density is reported. We observe a linear relationship between densification and tensile strength for all four studied MOFs, with the slope being MOF-dependent. We also report conditions for improving significantly the volumetric uptake. Finally, we evaluated our tablets' stability over time in the presence of moisture

Fabrication of an Active Electronic Device Using a Hetero-bimetallic Coordination Polymer

A nickel(II)/lead(II) coordination polymer [(NCS)Pb(H2O)LNi(NCS)]n {H2L=N,N′-bis(3-methoxysalicylidene)propane-1,3-diamine} has been synthesized and characterized. The band gap (3.18 eV) calculated from Tauc’s plot suggests the semiconducting nature of the complex. The material has a photosensitivity of 5.76, indicating its applicability in the fabrication of photosensitive devices. The complex has been successfully applied in a technologically challenging thin-film photosensitive Schottky device

Chemical instability of Cu(3)(BTC)(2) by reaction with thiols

In contrast to Fe(BTC) (BTC: 1,3,5-benzenetricarboxylate), the crystal structure of Cu3(BTC)2, a commercial metal organic framework widely used as solid catalyst, collapses when contacted with thiols under mild reaction conditions forming copper nanoparticles.Financial support by the Spanish DGI (CTQ2009-11587 and CTQ2010-18671) is gratefully acknowledged. Maykel de Miguel is thanked for helping to record TEM images.Dhakshinamoorthy, A.; Alvaro Rodríguez, MM.; Concepción Heydorn, P.; García Gómez, H. (2011). Chemical instability of Cu(3)(BTC)(2) by reaction with thiols. Catalysis Communications. 12(11):1018-1021. https://doi.org/10.1016/j.catcom.2011.03.018S10181021121

Hollow Y zeolite single crystals: synthesis, characterization and activity in the hydroisomerization of n-hexadecane

Hollow Y zeolite single crystals have been obtained from a conventional NaY zeolite following a three-step process involving a severe dealumination of the zeolite with silicon tetrachloride (step #1), followed by an acid washing under mild conditions (step #2) and finally a selective dissolution of the crystals core in the presence of protective Al species (step #3). Crystals are characterized by the presence of a regular internal cavity with 0.1–0.2 nm thick microporous walls. They contain a relatively low framework Al content but significant amounts of extraframework Al oxide species mainly located on the external surface of the crystals. Hollow crystals have been mixed with a Pt-supported alumina binder and used as catalysts in the hydroisomerization of n-hexadecane. Compared to the corresponding bulk crystals obtained after step #2, their higher activity has been attributed to a better efficiency, directly resulting from the presence of the cavity