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A series of oxonitridosilicates phosphors Ba-Si_x-O-N /Eu²⁺ (x=Si/Ba=1~8, 5atom% Eu²⁺) were synthesized using traditional solid-state reaction. For x = 2~8, the main phase of the obtained samples was Ba₃Si₆O₁₂N₂. All Ba-Si_x-O-N /Eu²⁺(x = 1~8) materials could be efficiently excited in the UV to visible region(310~450nm) and had a green emission at 508~522nm, making them attractive as conversion phosphors for white LED applications. With increasing x values, the emission peaks shifted to the longer wavelength region, while the emission intensity had a maximum at x = 6. The influence of the firing times was also discussed, after twice fired, there was a tendency of single-phased formed of the obtained materials and the emission intensity was greatly improved.

Crystal structure was refined on Sr-Nb and Sr(La)-Nb oxynitride perovskites prepared through citrate route by using neutron diffraction. The former had the composition of SrNbO_2.11N_0.89 and crystallized in I4/mcm with a = 0.57099(2) nm, c = 0.81015(5) nm having excess oxide ions in apical 4a site around Nb being compared to the cis-TaO₄N₂ octahedra in SrTaO₂N. The latter crystallized in the same space group with Sr_0.81La_0.19 having a = 0.57126(3) nm, c = 0.81055(6) nm. It was assumed that Sr_0.81La_0.19O_1.90N_1.10 has similar O/N occupancy in both apical 4a and equatorial 8h sites. The La substitution made the O/N occupancies equilibrated around Nb. The niobium valency was slightly less than five in these oxynitride perovskites.

Using Eu₂O₃, BaCO₃, Si₃N₄ and SiO₂ as starting materials, we succeeded in synthesizing BaSi₄O₆N₂:Eu${}^{2+}$ by firing the mixture at 1100^∘C for 2h in a reducing atmosphere (N₂(95%)–H₂(5%)). As a result, a single phase was obtained by setting the charge composition ratio to Si/$\mathrm{\text{Ba}}=6$. When the Eu${}^{2+}$ activation amount was 1%, it showed a broad emission in the range of 400–600nm under the excitation light of ultraviolet rays at 320nm. This phosphor exhibited chromaticity coordinates of $(x,y)=(0.258,0.297)$ under irradiation with ultraviolet rays at 320nm and is thought to be a promising phosphor for ultraviolet-excited white LEDs.

We synthesized rock-salt-type Li–Ti oxynitride (LiTi${}_n$O${}_x$N${}_y$, $n=1$, 1.25, 1.5, 1.75, and 2) using solid-phase reaction. The best charge/discharge characteristics were obtained with a Ti/Li ratio of 1.25, and the maximum discharge capacity was 140 mAh/g.

Diffuse reflectivity in the longer wavelength region after the absorption edge was studied on the LaTiO₂N nitrided. It was discussed in the viewpoint of particle sizes by use of ball milling and bead milling technique. The diffuse reflectivity after absorption edge of the LaTiO₂N powders got lower in accordance with the reduction of particle sizes. In case of LaTiO₂N aqueous suspension after the bead-milling treatment in which the primary particles were well dispersed, remarkable enhancement of the diffuse reflectivity was observed with decreasing the average particle sizes.