Codopant ion-induced tunable upconversion emission in β-NaYF4:Yb3+/Tm3+ nanorods

Area of Science:

• Materials Science
• Nanotechnology
• Photonics

Background:

• Upconversion (UC) emission is crucial for various photonic applications.
• Tuning UC emission in rare-earth doped materials like beta-sodium yttrium fluoride (β-NaYF4) is challenging.
• Controlling UC processes requires understanding ion interactions and local environments.

Purpose of the Study:

• To develop an innovative method for tuning UC emission in β-NaYF4:Yb3+/Tm3+ nanorods.
• To investigate the effect of codoping a third rare-earth ion on UC luminescence.
• To explore the influence of codopant concentration and temperature on UC emission properties.

Main Methods:

• Synthesized β-NaYF4:Yb3+/Tm3+ nanorods.
• Introduced a third rare-earth ion as a codopant.
• Utilized continuous wave (CW) excitation at 976 nm.
• Analyzed UC emission spectra dependence on codopant concentration and temperature.

Main Results:

• Successfully tuned UC emission by codoping with a third rare-earth ion.
• Demonstrated that UC luminescence tuning is achieved through a tailored local environment and controlled depopulation of excited states.
• Observed that codopant ions alter ion distribution and inter-ion distances, enhancing UC system sensitivity.

Conclusions:

• Codoping with a third rare-earth ion offers an effective route to tune UC emission in β-NaYF4:Yb3+/Tm3+ nanorods.
• The observed tuning mechanism is linked to modifications in the local ionic environment and excited-state dynamics.
• This approach provides greater sensitivity to impurity ions compared to downconversion systems, opening new avenues for UC material design.