The z value dependence of photoluminescence in Eu^[2+]-doped β-SiAlON (Si_[6-z]AlzOzN_[8-z]) with 1 ≤ z ≤ 4

Eu^[2+]-doped β-SiAlON (Si_[6-z]AlzOzN_[8-z]) phosphors with 1 ≤ z ≤ 4 were synthesized by gas pressure sintering. The emission spectra exhibit two broad bands with maxima at about 415 nm (violet) and 540 nm (green) under ultraviolet excitation. The green emission is dominant at z ≤ 2, while the violet emission becomes dominant at z > 2. The combination of two emission bands in a compound could lead to a white emission in Eu^[2+]-doped β-SiAlON with 2 < z ≤ 3.