Effect of crystal structure and concentration on luminescence in Er3+:ZrO2 nanocrystals

The sol–emulsion–gel method is used for the preparation of Er3+ doped ZrO2 nanocrystals. The luminescence spectra and lifetime of the excited state 4I13/2 of Er3+ ions in ZrO2 nanocrystals are found to be sensitive to the crystal structure and dopant concentration. It is found that the luminescence lifetimes of 1.0 mol% Er3+ doped ZrO2 nanocrystals are 1.94 and 3.36 ms for 800 and 1000 °C heat-treated samples, respectively. The analysis suggests that modification of relaxation mechanism is due to the crystal structure of the host and concentration of ions.