Strongly luminescent mixed-metallic copper(I)-silver(I) coordination polymers with various Cu/Ag ratio were prepared by utilizing the isomorphous relationship of the luminescent parent homometallic coordination polymers (Φ(em) = 0.65 and 0.72 for the solid Cu and Ag polymers, respectively, at room temperature). The mixed-metallic polymer with the mole fraction of copper even as low as 0.005 exhibits a strong emission (Φ(em) = 0.75) from only the copper sites as the result of the efficient energy migration from the silver to the copper sites. The migration rates between the two sites were evaluated from the dependence of emission decays upon the mole fraction of copper.

Luminescent silver(I) halogenido coordination polymers [Ag 2 X 2 (PPh 3 ) 2 (bpy)] n (X = I, Br, Cl) have been prepared. The iodido and bromido complexes exhibit strong blue phosphorescence assignable to the 3 π−π*-excited-state of bpy, whereas the chlorido complex shows luminescence thermochromism due to the π−π*-state of bpy and charge transfer from the {Ag 2 Cl 2 } core to the bpy π*-orbital. Taking advantage of their structural similarities, we prepared a series of mixed-halogenido silver(I) complexes [Ag 2 (X x X′ (1−x) ) 2 (PPh 3 ) 2 (bpy)] n (X, X′ = I, Br, Cl) at varying molar fractions as solid solutions. The mixedhalogenido complexes are as strongly luminescent as their parent complexes. The detailed study of their structure and emissive properties revealed smooth energy migration between the luminescent units and modification of the luminescence properties based on the planarity of bpy.

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When treated at high temperatures, petroleum coke materials exhibit structures which are formed of graphitized closed tips. The external surface of these materials is mostly formed of hemispherical tips similar to those found in carbon nanotubes. By low-temperature fluorination using CF 4 radio-frequency plasmas, an opening mechanism of the closed tips occurs, thus allowing a drastic increase of possible intercalation into the structure. The interest for Li + storage in Li-ion batteries has been demonstrated by capacity measurements which show an enhancement of the Li + capacity retention into the host materials.