Tunable emission color of Gd2(MoO4)3:Yb3+, Ho3+, Tm3+ phosphors via different excitation condition

- Gd2(MoO4)3:Yb3+, Ho3+, Tm3+ phosphors were synthesized by sol-gel method.
- The emission color changes from green to blue and then to pink with the pulse width changing from 100 μs to 2000 μs.
- The emission color changes from green to yellow with the pulse frequency adjusting from 200 Hz to 4000 Hz.
- Multi-color and white light were realized under appropriate excitation condition.

The methods of modulating emitting color are greatly important for up-conversion phosphors to broaden their applications, ranging from information storage to surface display. In this paper, the Ho3+/Tm3+/Yb3+ tri-doped Gd2(MoO4)3 phosphors are synthesized by typical sol-gel method. It is found that the phosphors can radiate intense blue (475 nm), green (542 nm) and red (660 nm) up-conversion luminescence under 980 nm or 915 nm laser excitation. Especially, the emission color of the phosphors can be tuned from red to lavender by adjusting the excitation power of 980 nm or 915 nm continuous lasers. In addition, the up-conversion luminescence is also investigated under the excitation of 980 nm pulse laser. The emission color varies from green to blue and green to yellow by altering the pulse width and frequency, respectively. Combining the above methods, multi-color and white light are realized, indicating the potential application in dynamic colorful display.