LI Qian (1994-), female, Master candidate. E-mail: 1252476405@qq.com
Y2O3:xBi3+ (x=0.05-1.0% (mole fraction)) phosphors were synthesized by a solid-phase reaction route. Effect of Bi3+ concentration on the phase composition, microstructure and photoluminescence (PL) performance was investigated. The results show that the lattice parameter and cell volume of Y2O3 host increase with the increase of Bi3+ concentration. In addition, the phosphors are equiaxed grains, and the grain size increases gradually from 250 to 600 nm with the Bi3+ concentration increasing. The emission spectra of Y2O3:Bi3+ phosphors excited by ultraviolet light (λEX=335 nm) are composed of three broadband emission spectra centered at 370 nm, 410 nm and 483 nm. The ultraviolet-emission at 370 nm and blue-light emission at 410 nm appear due to 3Au→1Ag and 3Eu→1Ag electron transitions of S6 sites of Bi3+, respectively. The blue-green emission at 483 nm occurs due to 3B→1A electron transition of C2 sites of Bi3+. The Y2O3:0.25%Bi3+ phosphor shows the optimal PL performance. The concentration quenching occurs when Bi3+ concentration is higher than 0.25% due to the dipole-dipole interaction between Bi3+ ions. The color coordinate of Y2O3:0.25%Bi3+ is (0.159 2, 0.218 1), and the color rendering index Ra is 69.27, indicating that the as-synthesized blue-green phosphors have a broad application prospect in the field of white light-emitting diode.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |