Novel energy-transfer route and enhanced luminescent properties in YVO4:Eu3+/YBO3:Eu3+ composite

In this paper, YVO4: Eu3+/YBO3:Eu3+ composite was fabricated by chemical corrosion through a two-step hydrothermal process, i.e., first preparation of YBO3:Eu3+ nanocrystals and subsequent chemical corrosion by Na3VO4 solution. A novel energy-transfer and luminescent route via UV and VUV excitation was identified (YBO3 phase -> YVO4 phase -> Eu3+ ions in the YVO4 phase), which remained in the sample annealed at high temperature. In this composite high quantum yield was maintained, and considerably improved color purity was induced. A corrosive interface between the YVO4: Eu3+ and YBO3: Eu3+ phases was identified by the site-selective excitation technique, where the local environment surrounding Eu3+ was extremely complex. It is believed that, through further optimization, this novel composite can be candidate phosphors for red PDPs and Hg-free fluorescent lamp in the future.