Facile preparation of edelweiss-like ZnO microparticles with strong UV-violet emission

Abstract Here, a single-step wet-chemical synthetic approach to fabricate novel hierarchically-structured edelweiss-like ZnO microparticles is reported. The construction of microparticles with an average size of 2.7 μm was accomplished within 3 min via hydrolysis of tetraamminezinc (II) complex at dynamic underwater Leidenfrost conditions. The possible formation mechanism of the microparticles was discussed and their microstructural and optical properties were examined. Photoluminescence studies at room temperature showed that the as-prepared ZnO possesses an intense UV-violet emission (370–422 nm range), while the low-temperature annealing at 200 °C leads to the predominant UV-violet-blue co-emission. In addition, the relationship between the photoluminescence properties of microparticles and the type of intrinsic defects in ZnO was analyzed.