Vapor Phase Synthesis of Upconverting Y₂O₃Nanocrystals Doped with Yb³⁺, Er³⁺, Ho³⁺, and Tm³⁺to Generate Red, Green, Blue, and White Light

We report the vapor phase synthesis of upconverting Y 2O 3 nanocrystals doped with Yb 3+, Er 3+, Ho 3+, and Tm 3+ to generate red, green, blue, and white light. Incorporating Er 3+ within the Yb 3+ doped Y 2O 3 nanocrystals under 980 nm laser excitation produced orange and yellow upconversion luminescence tunable by varying the Yb 3+ concentration. The Yb 3+, Er 3+, and Tm 3+ codoped Y 2O 3 nanocrystals exhibited nearly equal intensities of the red, green, and blue emissions upon 980 nm laser excitation. White light can be produced by adjusting the concentrations of the Ln 3+ ions within the Y 2O 3 nanocrystals.