Scalable and sustainable synthesis of superparamagnetic iron oxide nanoparticles using new tubular electrochemical system

A new tubular electrochemical system (TES) was developed to overcome scalability and sustainability challenges during synthesis of superparamagnetic iron oxide (Fe3O4) nanoparticles (SPIONs). The SPION yield and productivity were 8.3 mg mol−1 Fe and 163 µg mol−1 Fe min−1, respectively. The TES functions efficiently with electrolyte reuse and supplementation without any reduction in productivity. Gradual electrolyte supplementation (0.5 mL min−1) resulted in 75% higher yield than the non-supplemented system. TEM and XRD analyses confirmed the presence of Fe3O4. TES enables the use of a new reaction parameter—flow rate—for controlling SPION properties. Increasing electrolyte flow rate caused a decrease in SPION average size and size distribution. TES offers advantages of scalability and sustainability for large-scale production of Fe3O4 nanoparticles.