Structure and Luminescence of cubic boron nitride micropowder with neodymium ions

A neodymium-containing cubic boron nitride (cBN:Nd) micropowder was synthesized at high temperatures (1800–2000 K) and pressures (3.5–4 GPa) from a batch mixture of hexagonal boron nitride (hBN), a catalyst (Li3N), and NdF3 micropowder. Lattice constants of the cBN:Nd micropowder and a cBN standard micropowder (synthesized without adding NdF3) that were determined by x-ray diffraction were about 3.615 Å for both micropowders. Energy-dispersive x-ray spectral microanalysis showed that the cBN:Nd grain surface was covered with microinclusions and thin films of Nd-containing compounds. Luminescence spectrum measurements confirmed the presence of Nd3+ ions in the cBN:Nd micropowder. The Nd3+ emission in the spectral regions 1.2–1.1 and 1.50–1.35 eV was attributed to 4F3/2 → 4I11/2 and 4F3/2→ 4I9/2 optical transitions, respectively.