Abstract: A series of blue-white dual emission luminescent materials, Cd_0.5Zn_0.5B₄O₇∶Ce/Dy, were prepared via the high temperature solid state method for the first time. Investigating results of XRD show that Cd_0.41Zn_0.5B₄O₇∶Ce_0.04/Dy_0.02 belongs to orthorhombic crystal system with Pbca space group and lattice para-meters of a=1.3885 nm, b=0.8020 nm, c=0.8670 nm. There are two kinds of luminescence center, Ce³⁺ and Dy³⁺, in Cd_0.5Zn_0.5B₄O₇∶Ce/Dy system. Excited by 254—350 nm UV, the emission is mainly due to ⁴F_9/2→⁶H_15/2 and ⁴F_9/2→⁶H_13/2 of Dy³⁺, while excited by 355—390 nm UV, the emission is mainly due to 5d→4f of Ce³⁺. Excited by 340 nm UV, the intensity of the phosphor co-doped Ce/Dy is 31 times of the same concentration of Dy single-doped. Ce³⁺ is a high efficient sensitization agent of Dy³⁺. However, when excited by 355—390 nm UV, Dy³⁺ is the sensitization agent of Ce³⁺. A kind of singular two-way transfer of energy phenomenon, Ce³⁺→Dy³⁺ and Dy³⁺→Ce³⁺, exists in the system.

Key words: Cd_0.5Zn_0.5B₄O₇∶Ce/Dy, Blue-white dual emission, Two-way energy transfer