Preparation and Luminescence Properties of Gadolinium Aluminate Perovskite Phosphor Discrete Combinatorial Library

Combinatorial material synthesis and high throughput evaluation technique have been developed to accelerate material discovering and optimizing. The thin-film combinatorial material library (or material chip), similar to the integrated circuit chip, contains thousands even millions of different compounds, and could be used to screen for the desirable physical or chemical properties. In our work, the rare earth activated gadolinium aluminate perovskite phosphor(GAP:RE1(x), RE2(y), RE ion vary among Eu3+, Ce-3+,Ce- 4+, Pr-3+,Pr- 4+) combinatorial library is made by ion beam sputtering sequence deposition and two-step thermal processing. The GAP:RE1(x), RE2(y) combinatorial library indentify the "lead" red luminescent compound as GAP:Eu-0.11 from the 16 candidates with the help of the photoluminescent (PL) photograph under UV light. Three another compounds have been also picked out as GAP:Eu-0.1, GAP:Eu0.1Ce0.01, GAP:Eu0.1Pr0.01. Other than the information on "lead" compounds, the discrete combinatorial library provides a quick way to map out the relationships between activators and host, sensitizers and activators: 1) Eu3+ is a better red luminescent activator than Ce-3+,Ce-4+, Pr-3+,Pr- 4+ in GAP polycrystalline; 2)Neither Ce-3+,Ce- 4+ nor Pe(3+, 4+) is a proper sensitizer for Eu3+. The excitation and emission spectral indicate the resonance energy transfer between the activator and sensitizer must have happened, which leads to Ce-3+,Ce- 4+ or Pr-3+,Pr- 4+ codoping decrease Eu3+ red luminescence intensity. The candidates in powder form are prepared by nitric-citric method for more detailed characterization. All the screening results, obtained from the combinational library, are coherent with the powder phosphor experiments.