Ce和Dy在Cd0.5Zn0.5B4O7中的发光特性及能量双向传递

采用高温固相法制备了白蓝光双发射为一体的Cd0.5Zn0.5B4O7∶Ce/Dy系列发光材料. 由XRD测得Cd0.41Zn0.5B4O7∶Ce0.04/Dy0.02的晶胞参数: a=1.3885 nm, b=0.8020 nm, c=0.8670 nm, 属于正交晶系, Pbca空间群. 在Ce/Dy双掺的体系中存在Ce3+和Dy3+两种发光中心, 254~350 nm激发主要是Dy3+的 4F9/2→6H15/2和4F9/2→6H13/2跃迁发射, 而355—390 nm激发主要为Ce3+的5d→4f跃迁发射. 340 nm激发Ce/Dy双掺发光体的发射强度是同浓度Dy3+单掺的31倍, Ce3+是Dy3+的高效敏化剂, 而355—390 nm激发Dy3+是Ce3+的敏化剂. 体系中存在少见的Ce3+→Dy3+与Dy3+→Ce3+的能量双向传递.

Luminescence Characteristics and Two-way Energy Transfer of Ce and Dy in Cd0.5Zn0.5B4O7

A series of blue-white dual emission luminescent materials, Cd0.5Zn0.5B4O7∶Ce/Dy, were prepared via the high temperature solid state method for the first time. Investigating results of XRD show that Cd0.41Zn0.5B4O7∶Ce0.04/Dy0.02 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 Cd0.5Zn0.5B4O7∶Ce/Dy system. Excited by 254—350 nm UV, the emission is mainly due to 4F9/2→6H15/2 and 4F9/2→6H13/2 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.