Effect of sodium citrate on the shape and photoluminescence properties of CaWO4:Eu3+ superstructures synthesized by the hydrothermal method

Abstract

In this paper, we report a successful synthesis of monodisperse CaWO₄:Eu³⁺ superstructures by a surfactant-assisted hydrothermal process. The formation of the superstructures is strongly dependent on reaction parameters such as surfactant concentration, temperature and reaction time. The citrate concentration has significant influence in the resulting morphologies by selectively binding to the nuclei facets inducing preferential crystalline growth. In search of the formation mechanism of monodisperse CaWO₄:Eu³⁺ superstructures, extensive characterization has been performed by using XRD, FE-SEM, TEM, HRTEM and SAED. The growth mechanism of monodisperse CaWO₄:Eu³⁺ superstructures was proposed and their photoluminescence properties are discussed.