Preparation of Compensation Ions Codoped SrTiO3:Pr3+ Red Phosphor with the Sol-Gel Method and Study of Its Luminescence Enhancement Mechanism

SrTiO3:Pr3+ is the most representative titanate matrix red phosphor for field emission display (FED). The red luminous efficiency of SrTiO3:Pr3+ will be greatly improved after the compensation ions codoping, so SrTiO3:Pr3+ red phosphor has been a research focus at home and abroad. SrTiO3:Pr3+, SrTiO3:Pr3+, Mg2+, and SrTiO3:Pr3+, Al3+ phosphors are synthesized by a new sol-gel method. Crystal structure, spectral characteristics, and luminescence enhancement mechanism of the sample were studied by XRD and PL spectra. The results showed that after co-doped, SrTiO3:Pr3+ phosphor is single SrTiO3 cubic phase, the main emission front is located at 614？nm, corresponding to Pr3+ ions 1D23H4 transition emission. SrTiO3:Pr3+, Mg2+ and SrTiO3:Pr3+, Al3+ phosphor luminescence intensity is enhanced, but the main luminescence mechanism is not changed. Acceptor impurity = Mg2+, Al3+ will replace Ti bit after being doped into the crystal lattice to form charge compensation corresponding defect centers to reduce the demand of Sr2+ or Ti3+ vacancy. While Sr-doped Pr will make lattice distortion and transition energy of 4f-5d is very sensitive to crystal electric field changes around Pr atom. Doping different impurities will make electric field distribution around the icon have a different change. It increases energy transfer of 4f-5d transition and improves the luminous intensity of SrTiO3:Pr3+ red phosphor. 1. Introduction Field emission display (FED) is a new display technology, with its high quality, low cost, large area of ？？attractive advantages, achieving broad development prospects. Compared with cathode-ray tubes (CRT), FED has the high image quality. At the same time, FED has the thinness of liquid crystal display (LCD) and the large area characteristics of plasma display (PDP). FED has a considerable advantage in luminous efficiency, brightness, viewing angle, and power consumption way. In addition, FED also has a high resolution, fast response, high temperature resistant harsh, antivibration shock, weak electromagnetic radiation, and low production cost and is easy to implement digital display and so on. Research found that SrTiO3:Pr3+ [1–3] is the most representative for FED display titanate matrix red phosphor in the perovskite structure. SrTiO3:Pr3+ phosphor generates red light when photoluminescence and cathode-ray excitation. And the red light’s coordinates is , , and it is very close to the American NTSC system providing an ideal red light. However, SrTiO3:Pr3+ material has a problem that Pr3+ ion luminous efficiency is low, limiting its application.