Preparation of Janus nanosheets via reusable cross-linked polymer microspheres template

摘要

Janus nanosheets have great potential applications in diverse fields to provide improved performance over conventional homogenous nanoparticles. A novel strategy to prepare Janus nanosheets by surface adsorption and the sol-gel process of trialkoxy silanes onto the reusable cross-linked polymer microspheres template is presented in this paper. Polymer microspheres were synthesized by inverse suspension polymerization, and the matched silanes were screened by molecular simulations. After adsorption and sol-gel of silanes onto microspheres surface, the microspheres were covered with silica-based membranes. The silica-based membranes were further selective modified and exfoliated from the microspheres surface to obtain Janus nanosheets. Microspheres could be easily recycled and reused. Two kinds of silica-based Janus nanosheets of carboxyl/alkyl composite and amide/alkyl composite were successfully prepared by the above approach. The synthesized nanosheets exhibited sheet-like morphology, Janus nature, interfacial activity and excellent ability to stabilize emulsions. This study provides a scalable method for the controllable synthesis of Janus nanosheets, which may provide a new avenue for their fundamental studies and practical applications.