Precipitation Synthesis and Color‐Tailorable Luminescence of α‐Zr(HPO4)2: RE3+(RE = Eu, Tb) Nanosheet Phosphors

The rare earth ( RE = Eu and Tb) ions‐doped α‐Zr( HPO 4 ) 2 (ZrP) nanosheet phosphors were synthesized by direct precipitation method, and their structures and photoluminescence properties were investigated. The results of X‐ray diffraction and scanning electron microscopy indicated that the systems of ZrP: RE 3+ had similar nanosheet structure except with relatively larger interlayer spacing as compared with pure α‐ZrP. Under the excitation of UV light, the ZrP: RE 3+ nanosheet phosphors showed red and green emission peaks corresponding to the 5 D 0 → 7 F 2 transition of Eu 3+ and the 5 D 4 → 7 F 5 transition of Tb 3+ , respectively. After Eu 3+ and Tb 3+ were co‐doped in ZrP host, not only the red and green emission peaks were simultaneously observed, but also the luminescent intensity and fluorescence lifetimes of Tb 3+ were gradually decreased with the increase in Eu 3+ ‐doping concentration, which implied the energy transfer from Tb 3+ to Eu 3+ happened. It was deduced that the energy transfer from Tb 3+ to Eu 3+ occurred via exchange interaction. Through optimization to the samples, a nearly white‐light emission with the color coordinate (0.322, 0.263) was achieved under 377 nm excitation. The ZrP: RE 3+ nanosheet phosphors may be a potential color‐tailorable candidate for fabricating optoelectronic devices such as electroluminescence panels.