Enhanced upconversion emissions of NaNbO3:Er3+/Yb3+ nanocrystals via Mg2+ ions doping

Abstract The rod-like NaNbO3:Er3+/Yb3+ nanocrystals codoped with Mg2+ ions were firstly synthesized by hydrothermal method. The effect of Mg2+ ions on the phase structure and morphology of NaNbO3:Er3+/Yb3+ was investigated by XRD and SEM spectra. Addition of Mg2+ ions enhanced the intensities of green and red UC emissions by about 3 times and prolonged the lifetime of the 4S3/2 → 4I15/2 transition of Er3+ ions. The pump power dependences were measured to understand the upconversion mechanism under 980 nm excitation. The tailored local environment of Er3+ ions by codoping Mg2+ ions was responsible for the improved optical characteristics of NaNbO3:Er3+/Yb3+/Mg2+ nanocrystals.