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In this study, luminescent electrospun nanofibers based on polyvinyl pyrrolidone (PVP)/Eu-PEG were prepared through the materials processing technique of electrospinning as an innovative type of phase change materials (PCMs). Eu-PEG phase-change luminescent material was prepared by coordinating rare earth Eu 3+ ions with the carboxylate groups of a PEG modified by two terephthalic acid groups. The morphology and thermal properties of the composite fibers were studied by field emission scanning electron microscopy (FE-SEM) and differential scanning calorimetry (DSC), respectively. The average diameter of PVP/Eu-PEG composite fibers measured from SEM images increased gradually with increasing PEG molecular weight. The fluorescence spectra of the prepared fibers were investigated. The results show that the PVP/Eu-PEG material has both good phase change properties and excellent luminescent properties.

A series of 2-(1H-benzimidazol-2-yl)-phenols and their nickel complexes have been synthesized and characterized by elemental and spectroscopic analysis. The molecular structures of ligand L4 and complex C5 were confirmed by X-ray diffraction analysis. X-ray crystallographic analysis revealed that complex C5 has a six-coordinated distorted octahedral geometry. Upon activation with Et2AlCl, these nickel(II) complexes showed good activity for ethylene oligomerization. When PPh3 was added as an auxiliary ligand to the catalytic system, an increased activity as high as 1.60 × 107 g mol−1 (Ni) h−1 was observed. The ligand environment and reaction conditions remarkably affected the catalytic behavior of these nickel complexes.

A series of chromium(III) complexes ligated by tridentate ligands of 2-imino-1,10-phenanthrolines, LCrCl3 (L = 2-(2,6-(R1)2C6H3N = CR)-1,10-phen) was synthesized and characterized by elemental and spectroscopic analyses as well as single-crystal X-ray crystallography. X-ray crystallographic analysis of 2 (R = Ph, R1 = Et), 4 (R = Me, R1 = Me) and 12 (R = H, R1 = i-Pr) reveals that the geometry around the chromium atom is octahedral. Upon activation with MAO, these complexes exhibited high activities for ethylene oligomerization (up to 1.15 × 107 g mol−1 (Cr) h−1) and moderate activities for ethylene polymerization. The oligomers and polymers obtained were α-olefins, and the distribution of oligomers resembled the Schultz–Flory rule. Various reaction parameters were investigated in detail, and the results revealed that both the steric and electric effects of ligands affected the catalytic activities of their chromium complexes as well as the distribution of the products.

Rare-earth metal-organic frameworks, [Ln 2 ( pydc ) 3 (H 2 O) 9 ] n 3 n H 2 O (Ln = Sm, Eu, Gd, Dy; pydc = pyridine-3,5-dicarboxylate), were synthesized and characterized by elemental analysis, IR spectra and single-crystal X-ray diffraction. The solid-state photoluminescence measurements exhibited red light-emitting characteristic of europium (III) coordination polymer. The title compounds consist of one-dimensional dual chains, in which each metal atom is nine-coordinated with oxygen atoms.