Fabrication Of Inorganic/Organic Composite Materials Templated From Two-dimensional Nanosheets-stabilized Pickering Emulsions

Pickering emulsion template plays a great role in preparing organic/inorganic composite materials. Owing to the less use of emulsifying agent, great stability and less toxicity, Pickering emulsion template have drawn great attention. In this study, we used low internal and high internal phase emulsion template stabilized by two kinds of two-dimensional nanosheets to prepare hybrid microsphere and porous composite material. The main contents and results of this study are listed as follows:1. Fabrication of Mo S2/polystyrene hybrid microsphere. For the first time, we used chemically exploited Mo S2(ce-Mo S2) to stabilize oil-in-water(O/W) Pickering emulsions. We systematically investigated the influences of salt in aqueous solution and ce-Mo S2 concentration on the stability of the emulsion, and thus confirmed the optimal recipe of the emulsion system. Pickering emulsion homogenized by mechanical force often resulted in polydispersity of the emulsion droplet which limits their practical applications. In order to obtain uniform emulsion droplet, membrane emulsification process was required. With the increasing of the passing times, the average sizes of the obtained droplets decreased. Hybrid microspheres were prepared by using emulsions after membrane extrusion. Scanning electron microscope(SEM) were adopted to survey the above two microspheres. The results show that the uniformity of the microspheres had been greatly improved after membrane extrusion. These hybrid particles could be served as stabilizers to form liquid marbles by rolling water droplets on a powder bed of the particles and followed by a solvent vapor treatment. It was demonstrated that the obtained liquid marbles exhibited good mechanical strength and consisted of a monolayer Mo S2/PS hybrid shell, having great potential applications in microcapsulation and surface chemistry.2. Fabrication of porous graphene oxide/melamine formaldehyde resin. Graphene oxide had been successfully prepared by modified Hummers’ method. The obtained graphene oxide cannot be used to stabilize oil in water high internal phase emulsions(HIPEs). It can be ascribed that the excess hydrophilicity and negative charge make GO not effectively prevent droplets from coalescence in a very concentrated state. For the first time, we used nanoparticle-modified graphene oxide to stabilize oil in water HIPEs. We systematically investigated the influences of p H, particle concentration and modify agent on the formation of Pickering emulsions, and thus confirmed the best recipe of the emulsion system. We used the above emulsion as a template, after polymerize the dispersed phase, the porous composite material had been prepared. SEM indicated the pore was closed.