Synthesis of Cu₂O Nanoparticles by Ellipse Curve Micromixer

Micromixers offer the advantage of rapid and homogeneous mixing compared with conventional macroscale reaction systems, and thus they show great potential for the synthesis of nanoparticles. An ellipse curve serpentine micromixer, which had been proposed in our prior works was employed to synthesize Cu₂O nanoparticles. Cu₂O are excellent photocatalysts that have been widely utilized in the degradation of organic dyes. Owing to the excellent mixing performance, the reduction of Cu(OH)₂ in micromixing synthesis was more sufficient than that in conventional stirring synthesis. The Cu₂O nanoparticles synthesized by micromixing had smaller size and narrower size distribution compared with those synthesized by stirring in a beaker. The smallest Cu₂O nanoparticles were obtained by micromixing with Re = 100 at T = 60 °C, while the most uniform Cu₂O nanoparticles were obtained at T = 80 °C owing to Ostwald ripening. Through the photocatalytic degradation experiments of Rhodamine B, the Cu₂O nanoparticles synthesized by micromixing were found to have better photocatalysis than those synthesized by stirring. The research results showed that the micromixing synthesis was a more suitable choice to produce Cu₂O nanoparticles with excellent photocatalysis. The ellipse curve micromixer with a simple structure and high mixing performance can be applied in the synthesis of various nanoparticles.