ChemInform Abstract: A New MCM-41 Supported HPF6Catalyst for the Library Synthesis of Highly Substituted 1,4-Diyhdropyridines and Oxidation to Pyridines: Report of One-Dimensional Packing Towards LMSOMs and Studies on Their Photophysical Properties.

Ordered mesoporous silica, SBA-15 and MCM-41, and three-dimensionally ordered macroporous SiO2 were used as the supports of H4PMo11VO40 heteropolyacid for methacrolein oxidation. The dispersion and structural evolutions of the heteropolyacid along with thermal treatment were investigated. It was found that the heteropolyacid entered the one-dimensional mesoporous channels of SBA-15 and MCM-41, and the crystallization and growth were limited, leading to high dispersion of the heteropolyacid. However, the thermal stability was decreased under high dispersion. The migration of the heteropolyacid was observed to the end of the one-dimensional channels of SBA-15 and the outer surface of MCM-41 with calcination, accompanied by the decomposition of the heteropolyacid and the formation of MoO3. In comparison, the crystallization and growth of heteropolyacid were not limited in the open macropores of three-dimensionally ordered macroporous SiO2. Dispersed particles on the surface of the macropores with size of about 5 nm exhibited a higher thermal stability. The decomposition of the heteropolyacid in the SBA-15 and MCM-41 supported catalysts resulted in the loss of strong acid sites, causing low selectivity to methacrylic acid in methacrolein oxidation. High thermal stability with high exposure of the active sites in the three-dimensionally ordered macroporous SiO2 supported catalyst contributed to the enhancement in the catalytic performance.

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Electrospinning preparation and photophysical properties of one-dimensional (1D) composite nanofibers doped with erbium(III) complexes

Journal of Luminescence ◽

10.1016/j.jlumin.2010.02.024 ◽

2010 ◽

Vol 130 (8) ◽

pp. 1343-1348 ◽

Cited By ~ 15

Author(s):

Xu Sun ◽

Bin Li ◽

Luting Song ◽

Jian Gong ◽

Liming Zhang

Keyword(s):

Composite Nanofibers ◽

Photophysical Properties ◽

One Dimensional

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Investigation of the Photophysical Properties of a Eu3+ Coordination Polymer Bearing an α-Nitrile Substituted β-Diketonate Ligand via Emission and Ultrafast Transient Absorption Spectroscopy

Australian Journal of Chemistry ◽

10.1071/ch15253 ◽

2015 ◽

Vol 68 (9) ◽

pp. 1392 ◽

Cited By ~ 4

Author(s):

Brodie L. Reid ◽

Evan G. Moore ◽

Brian W. Skelton ◽

Mark I. Ogden ◽

Massimiliano Massi

Keyword(s):

Coordination Polymer ◽

Absorption Spectroscopy ◽

Transient Absorption ◽

Photophysical Properties ◽

Transient Absorption Spectroscopy ◽

Quantum Yields ◽

Metal Centre ◽

Antenna Effect ◽

One Dimensional ◽

Polymer Bearing

Reaction of the β-diketone ligand, 2-cyano-1,3-phenyl-1,3-propandione (LH), with hydrated EuCl3 in the presence of 1,10-phenanthroline (Phen), results in the crystallisation of a one-dimensional Eu3+ coordination polymer of formulation [Eu(Phen)(L)3]∞, formed by coordination of the nitrile group of an O,O′-bound ligand to a neighbouring metal centre. An investigation of the metal-centred emission of the polymer, both in the solid state and solution, revealed red emission characterised by relatively long-lived excited state lifetimes and high intrinsic quantum yields. However, analysis of the overall quantum yield and sensitisation efficiency reveals that ultrafast processes in the ligand potentially inhibit Eu3+ sensitisation. Further investigations into these processes using transient absorption spectroscopy suggest that substitution at the α-C position may significantly decrease sensitisation via the antenna effect.

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