Dependence of the up-conversion emission of Li⁺ co-doped Y2O3:Er³⁺ films with dopant concentration

Abstract The effect of dopant concentration on the up-conversion emission, and in particular on the Er³⁺ related green and red emissions of spray pyrolysis deposited films of Y2O3:Er³⁺ co-doped with Li⁺, is reported. Er³⁺ concentrations in the films in the range of 1.1-5.6 at% (1.5-14 at% Er³⁺ in the spraying solution) were studied, as well as the effect of co-doping them with Li⁺. Large concentrations of Er³⁺ favor the red emission, especially for contents higher than 10 at% in the spraying solution. Li⁺ co-doping improves the green and red emissions up to 365 and 171 times, respectively, depending on the Er³⁺ and Li⁺ concentrations.