A Novel Double-Diamond Microreactor Design for Enhanced Mixing and Nanomaterial Synthesis

This study introduces the Double-Diamond Reactor (DDR), a novel planar passive microreactor designed to overcome the following conventional limitations: inefficient mass transfer, high flow resistance, and clogging. The DDR integrates splitting–turning–impinging (STI) hydrodynamic principles via CFD-guided optimization, generating chaotic advection to enhance mixing. Experimental evaluations using Villermaux–Dushman tests showed a segregation index (Xs) as low as 0.027 at 100 mL·min−1, indicating near-perfect mixing. In BaSO4nanoparticle synthesis, the DDR achieved a 46% smaller average particle size (95 nm) and narrower distribution (σg=1.27) compared to reference designs (AFR-1), while maintaining low pressure drops (<20 kPa at 60 mL·min−1). The DDR’s superior performance stems from its hierarchical flow division and concave-induced vortices, which eliminate stagnant zones. This work demonstrates the DDR’s potential for high-throughput nanomaterial synthesis with precise control over particle characteristics, offering a scalable and energy-efficient solution for advanced chemical processes.