Microfluidic Flow Synthesis of Functional Mesoporous Silica Nanofibers with Tunable Aspect Ratios

Microfluidic techniques open new frontiers for the controllable synthesis of functional micro/nanomaterials with desired shapes for a variety of applications. In this study, miniaturized spiral-shaped microchannel with two inlets and one outlet was specially designed for the controllable flow synthesis of mesoporous silica nanofibers (MSNFs) using one inlet flow containing cetyltrimethylammonium bromide and diluted ammonia and the other inlet flow containing diluted tetraethyl orthosilicate. The aspect ratios and diameters of MSNFs can be easily tuned by changing the flow rates and/or the concentrations of reactants. In addition, fluorescent dyes, magnetic nanoparticles, therapeutic drugs, or silver nanoparticles can be simultaneously assembled into MSNFs to make them promising functional materials in bioimaging, theranostics, and catalysis fields.