Table 2 The integrated UC intensities of particular emission bands, their ratios and CIE chromaticity coordinates of synthesized β-NaYF4:Er3+,Yb3+@NaYF4 CSNP.
Laser power density (W/cm2) | Relative integrated intensities | CIE | ||||
|---|---|---|---|---|---|---|
2H11/2 → 4I15/2 | 4S3/2 → 4I15/2 | 4F9/2 → 4I15/2 | IGreen/IRed | x | y | |
0.73 | 7.83 | 15.66 | 76.51 | 0.31 | 0.336 | 0.331 |
1.59 | 15.52 | 19.14 | 65.34 | 0.53 | 0.339 | 0.351 |
3.02 | 18.58 | 20.97 | 60.45 | 0.65 | 0.341 | 0.407 |
4.19 | 23.33 | 21.48 | 55.19 | 0.81 | 0.334 | 0.456 |
5.34 | 25.36 | 21.60 | 53.04 | 0.89 | 0.329 | 0.490 |
6.50 | 26.89 | 23.61 | 49.50 | 1.02 | 0.321 | 0.515 |
7.64 | 29.67 | 24.18 | 46.15 | 1.17 | 0.313 | 0.524 |
8.80 | 31.78 | 25.17 | 43.06 | 1.32 | 0.308 | 0.530 |
9.95 | 32.53 | 25.12 | 42.35 | 1.36 | 0.306 | 0.526 |