Europium (III) complex functionalized Si-MCM-41 hybrid materials with visible-light-excited luminescence

Thermosensitive visible-light-excited visible-/NIR-luminescent complexes with lanthanide sensitized by the π-electronic system through intramolecular H-bonding

Visible-luminescent lanthanide (LnL) complexes with a highly planar tetradentate ligand were successfully developed for a visible-light solid-state excitation system. L was designed by using two 2-hydroxy-3-(2-pyridinyl)-benzaldehyde molecules bridged by ethylenediamine, which was then coordinated to a series of Ln ions (Ln = Nd, Sm, Eu, Gd, Tb, Dy, and Yb). From the measurement of single-crystal X-ray analysis of EuL, two phenolic O atoms and two imine N atoms in L were coordinated to the Eu ion, and each π-electronic system took coplanar with the edged-pyridine moiety through an intramolecular hydrogen bond. The enol group on the phenolic skeleton changed to the keto form, and the pyridine was protonated. Thus, intramolecular proton transfer occurred in L after the complexation. Other complexes take isostructure. The space group is P-1, and the c-axis shrinks with decreasing temperature without a phase transition in EuL. The yellow color caused by the planar structure of L can sensitize ff emission by visible light, and the luminescence color of each complex depends on central Ln ions. Furthermore, a phosphorescence band also appeared at rt with ff emission in LnL. Drastic temperature dependence of luminescence was clarified quantitatively.

Studying the hydrogen atom position in the strong-short intermolecular hydrogen bond of pure and 5-substituted 9-hydroxyphenalenones by invariom refinement and ONIOM cluster computations

The solid-state structures of three H-bonded enol forms of 5-substituted 9-hydroxyphenalenones were investigated to accurately determine the H atom positions of the intramolecular hydrogen bond. For this purpose, single-crystal X-ray diffraction (SC-XRD) data were evaluated by invariom-model refinement. In addition, QM/MM computations of central molecules in their crystal environment show that results of an earlier standard independent atom model refinement, which pointed to the presence of a resonance-assisted hydrogen bond in unsubstituted 9-hydroxyphenalone, are misleading: in all our three and the earlier solid-state structures the lowest energy form is that of an asymmetric hydrogen bond (CS form). Apparent differences of results from SC-XRD and other analytical methods are explained.

Host–guest luminescent materials based on highly emissive species loaded into versatile sol–gel hosts

By mostly focusing on the findings of our group, this concise review provides insights into the development of promising new host–guest optical materials based on sol–gel assemblies of versatile hosts and highly luminescent guests.

Photoelectrochromic devices based on cobalt complex electrolytes

Three cobalt complexes are introduced into a PECD as the redox couples and a self-powered coloring/bleaching process of cobalt electrolyte-based PECDs is achieved for the first time.

Core–shell structured Gd2O3:Ln@mSiO2 hollow nanospheres: synthesis, photoluminescence and drug release properties

Core–shell structured Gd₂O₃:Ln@mSiO₂ hollow microspheres with an interesting double-shell and mesoporous structure have been fabricated. The luminescent composite shows obvious drug storage and release properties.