Synthesis of ZnO hollow microspheres via an in-situ gas growth method

Large-scale ZnO hollow spheres were fabricated by a novel in-situ gas growth method. The key strategy for the successful realization was that we employed a high concentration of H2O2 in the preparation procedure. The whole process was carried out under hydrothermal condition without any assistance of surfactant. The O2 bubbles, originating from the in-situ decomposition of H2O2, served as a soft template. The morphology, structure, composition and catalytic activity of the product have been investigated with XRD, SEM, TEM and TG-DSC. In order to demonstrate the important roles of reactive temperature, H2O2 and urea concentration, a series of controlled experiments have been carried out. It was worth noting that hexagonal wurtzite ZnO made up of various ZnO single-crystal nanosheets could be obtained, when we changed the concentration of urea to 0.4 M. In addition, the fabrication mechanism of ZnO hollow microspheres was discussed in detail. Moreover, the product showed high effective catalytic activity on the decomposition of ammonium perchlorate.

In situ gas growth approach was demonstrated to prepare ZnO hollow microspheres. The O2 bubbles, originating from the in-situ decomposition of H2O2, served as a soft template. When changed the concentration of urea to 0.4 M, ZnO microspheres consisting of various single-crystal nanosheets were obtained. The hollow microspheres showed high effective catalytic activity on the decomposition of NH4ClO4.Figure optionsDownload as PowerPoint slideHighlights
► An in-situ gas growth approach was demonstrated to prepare ZnO hollow microspheres.
► O2 bubbles, originating from decomposition of H2O2, served as a soft template.
► The sample showed high effective catalytic activity on the decomposition of KMnO4.