Controllable Preparation And Utilization Of Janus Mesoporous Materials

Mesoporous materials are attracting widespread attention of the field of materials for high degree of orderliness,large specific surface area and adjustable aperture,and Janus mesoporous materials of special microstructure and capability are being an important research direction of the field of materials.However,the research about manufacture and utilization of Janus colloid now is mostly focusing on Janus particles,but Janus nanosheets with special structure is less reported.The chemical composition and pattern of Janus mesoporous nanosheets are asymmetric,so Janus nanosheets are better than Janus particles for the stabilization of emulsion,and this makes Janus nanosheets have broad application prospects in separation,biomaterials and catalyst.But the complexity of Janus structure makes Janus mesoporous materials hard to prepare,meanwhile,the preparation methods of Janus mesoporous materials nowadays are always limited,so the problem of controllable and large-scale preparation of Janus mesoporous materials must be solved.In this paper we prepared Janus mesoporous nanosheets around the scientific and technical problems which mentioned above,and we researched how magnetically responsive surfactant affects mesoporous materials at last.The paper presents a simple and convenient method to prepare Janus mesoporous nanosheets,emulsion interface provides Janus environment,sol-gel process is adopted,silane coupling agents are used as the precursor of SiO2,then kinds of precursors and certain surfactants self-assembled at the emulsion interface by sol-gel process,finally Janus mesoporous nanosheets are gained.It is first reported that how oil-water ratio,silane coupling agents,surfactants and solvents affect the pore and thickness of Janus mesoporous nanosheets in this paper.We confirmed appropriate conditions of different Janus mesoporous nanosheets(50 g water,20 g decane,1.0 g SDS,0.4 g TEOS,0.08 g APTMS,0.11 g PTES;or 50 g water,20 g decane,0.5 g CTAB,1.0 g TEOS,0.4 g APTMS),and prepared Janus mesoporous nanosheets of ideal pattern and structure(the thickness is 7 nm,specific surface area is 495 m2/g,average pore diameter is 9.8 nm).A certain surfactant and FeCl3 are chose to synthesize a magnetically responsive surfactant.The magnetically responsive surfactant is used as template,silane coupling agent is used as the precursor of SiO2,and then the precursor and the certain surfactant self-assembled at the emulsion interface by sol-gel process,finally the affection of magnet to the mesoporous materials are analyzed.The pore structure changed in applied magnetic field which proves the method that pore structure could be changed by preparing mesoporous materials of magnetically responsive surfactants in applied magnetic field is available.