Continuous Preparation of Size-Controllable BaTiO3 Nanoparticles in a Rotor–Stator Spinning Disk Reactor

Abstract

The controlled synthesis of BaTiO3 nanoparticles (BTNPs) with a small particle size and a narrow particle size distribution (PSD) is key for the preparation of multilayer ceramic capacitors with high capacitance and high volumetric efficiency. This paper reports the research to continuously synthesize nanoparticles in a rotor–stator spinning disk reactor (RSSDR) for the first time and obtain BTNPs with a mean particle size (MPS) of 15.71 nm and a yield of 280 g/h. The MPS and PSD of BTNPs are related to the rotor–stator distance, the rotational speed, the volume flow, the molar ratio of Ba to Ti, and the flow rate ratio. The results show that the increasing micromixing efficiency of the RSSDR weakened the influence of mixing restriction on the chemical reaction. However, the enhancement of mass transfer is accompanied by the shortening of residence time, which has a negative impact on the synthesis of BTNPs. Moreover, BTNPs prepared in the RSSDR show superior results compared with other reactors. In addition, a novel dispersion method was proposed to control particle agglomeration in the glycerol matrix and the dispersion effectiveness was verified by comparing transmission electron microscopy results with dynamic light scattering results. The polydispersity index of each result was below 0.200. In conclusion, a large-scale continuous preparation of BTNPs with a controllable particle size can be achieved in the RSSDR.