A novel red-emitting Mn-activated BaZnOS phosphor

A novel Mn-activated BaZnOS phosphor, designed to achieve an intense red emission for white LED use, was systematically investigated. UV–Vis diffuse reflectance spectra showed a direct band gap of 3.9 eV for the host material. The phosphor efficiently emitted red light under UV excitation. As the Mn concentration increased, the emission peak remained unchanged at 623 nm. The maximum photoluminescence (PL) intensity of the high-brightness red-emitting phosphor occured at the optimal Mn concentration of x = 0.005 (x: the doping Mn concentration per mol of BaZnOS). The decay time of BaZn0.998OS:0.002Mn was measured to be 1.24 ms. The air-stable quaternary oxysulfide phosphor is a promising candidate to be applied in UV white LED and display devices.