Microfluidic emulsification techniques for controllable emulsion production and functional microparticle synthesis

•Microfluidic emulsification for controllable emulsion production is introduced.•Microfluidic emulsions show controllable size, shape, composition and structure.•Tuning the packed structures of interfacial surfactants varies emulsion structures.•Emulsion-template syntheses of controllable functional microparticles are reviewed.•Interplay between the mesoscale features of microparticles achieves desired functions.