Synthesis and photoluminescence properties of divalent europium doped-CaAlSi_1+2xN_3+2xO_x (x = 0-1) solid solution phosphors

The calcium cyanamide (CaCN₂) reduction route was applied for the synthesis of the Eu²⁺ (2 at%)-activated CaAlSi _1+2xN_3+2xO_x (x = 0-1) phosphors, and the impact of oxygen content on photoluminescence properties was investigated. The relationship of crystallographic parameters of the solid solution and oxygen content were also studied. All of the samples showed a broadband excitation covering the range from UV to visible region, revealing that this phosphor was a potential candidate for the phosphor-converted white LEDs. Under the UV/blue excitation, this series phosphor gave the emission peaks varying from 585 to 641 nm. The shifting behavior was dominantly contributed to the second luminescent center formed by the introduction of oxygen into nitride phosphors.