Monodispersed hollow microsphere of ZnO mesoporous nanopieces: Preparation, growth mechanism and photocatalytic performance

Abstract The mesoporous ZnO nanopieces-based nest-like hollow microsphere are successfully synthesized through the thermal decomposition of hydrozincite (Zn 5 (CO 3 ) 2 (OH) 6 ) formed by a facile hydrothermal method. The time-dependent experiments reveal the unique growth process of hydrozincite (Zn 5 (CO 3 ) 2 (OH) 6 ) microsphere. Hydrozincite Zn 5 (CO 3 ) 2 (OH) 6 nanopiece clusters were formed via homogenous nucleation process at the initial stage, these hydrozincite nanopieces assemble into the ring-like structures through a complex secondary nucleation with the growth of Zn 5 (CO 3 ) 2 (OH) 6 crystalline at the edge of each nanopiece, and further formed the hollow microspheres. Study show ZnO inherits well the size and morphology of hydrozincite crystals after the thermal decomposition. Nest-like hollow microspheres of ZnO mesoporous nanopieces are monodispersed with a uniform size distribution of ∼15 μm. Study also shows ZnO nanopieces interwaved microspheres with high surface area and porosity exhibit excellent photocatalytic activitiy on the photodegradation of methyl orange.