Divalent europium-doped nitride phosphors, Ca 1-x Eu x AlSiN 3 (x ) 0-0.2), were successfully prepared by the self-propagating high-temperature synthesis (SHS) by using Ca 1-x Eu x AlSi alloy powder as a precursor. The Rietveld refinement analysis was carried out on the CaAlSiN 3 host lattice to elucidate the luminescence properties of dopant Eu 2+ on the tetrahedrally coordinated site. For the Eu 2+ doped samples, strong absorption peaking at about 460 nm was observed on the excitation spectra, which matched perfectly with the current blue light of InGaN/GaN light-emitting diodes (LEDs). The optimized sample, Ca 0.98 -Eu 0.02 AlSiN 3 , gave the red emission peaking at 649 nm of which the intensity was competitive with the sample prepared from the metal nitride raw materials (Ca 3 N 2 , AlN, Si 3 N 4 , and EuN). The CIE chromaticity index (0.647, 0.347) with high color saturation indicated that it was a promising candidate as a redemitting phosphor for the InGaN/GaN-based down-conversion white LEDs for general illumination or displays.

Eu 2 + -doped ternary nitride phosphor, Sr2Si5N8:Eu2+, was prepared by the carbothermal reduction and nitridation method. The Rietveld refinement analysis showed that the single phase products were obtained. Two main absorption bands were observed on the diffuse reflection spectra peaking at about 330 and 420nm, so that the resultant phosphor can be effectively excited by InGaN light-emitting diodes. The emission peak position of (Sr1−xEux)2Si5N8:Eu2+ series varied from 618to690nm with increasing Eu2+ ion concentration. The redshift behavior of the emission band was discussed on the basis of the configuration coordination model.

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Fe nanowires with 70–200nm in diameter and 20–50μm in length were synthesized by a chemical vapor deposition method for electromagnetic wave absorption application. The frequency dependences of relative permittivity (εr) and permeability (μr) were strongly dependent on the diameter of Fe wires. Compared with micrometer wires or flakelike samples, nanowires exhibited a magnetic resonance (μr″) peak in the range of 1–18GHz, suggesting that nanowires have significant effect for reducing the eddy current loss, therefore, the resin compacts of 29vol% Fe nanowires with thicknesses of 1.3–4.0mm provided good electromagnetic wave absorption performances in the range of 5.6–18GHz.