Controllable morphology and tunable colors of Mg and Eu ion co-doped ZnO by thermal annealing

Abstract

Mg²⁺ and Eu³⁺ co-doped ZnO nanostructures were prepared by an environmentally friendly method. With an increase in the annealing temperature, the Mg²⁺ and Eu³⁺ co-doped ZnO nanosheets, composed of aggregated crystallites, experienced structural evolution from individual nanochains to partially sintered short rods and finally smooth nanorods. Consequently, the optical properties of Mg²⁺ and Eu³⁺ co-doped ZnO changed accordingly, shown here for white, green and yellow emitting segments. This study on the correlation between the sintered structure and optical properties shows that controlled thermal annealing affects the stress through structural evolution of the Mg²⁺ and Eu³⁺ co-doped ZnO nanocrystallites.