Preparation and photoluminescence properties of Er3+-doped La2Zr2O7 nanocrystals

• The Er3+-doped La2Zr2O7 nanocrystals show uniform spherical with the size of 25 nm.
• The Er3+-doped La2Zr2O7 nanocrystals exhibit a defect fluorite-type structure.
• The emission intensity has a maximum at Er3+ content between x = 0.025 and x = 0.05.

(La1−xErx)2Zr2O7 (x = 0, 0.025, 0.05, 0.075, 0.1) nanocrystals have been successfully prepared by the chemical co-precipitation and calcination method, and were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and photoluminescence spectroscopy. The nanocrystals calcined at 800 °C for 5 h exhibit good crystallinity and have a particle size of about 25 nm. The emission band centered at 528 nm is identified as the 2H11/2 → 4I15/2 transition, the emission bands centered at 550 nm and 562 nm are attributed to the 4S3/2 → 4I15/2 transition, and the emission bands centered at 663 nm and 682 nm are ascribed to the 4F9/2 → 4I15/2 transition. The emission intensity increases with increasing Er3+ content, up to a critical concentration between x = 0.025 and x = 0.05, and then decreases with further increasing Er3+ concentration.