Patchy Template Synthesis Of Porous Hollow Spheres

Porous hollow microspheres not only have the advantages of hollow structures such as large internal storage capacity,low density and large specific surface area,but also the pore structure on the shell meets the needs for controlled release of functional materials,high loading capacity and so on.Therefore,porous hollow microspheres have wide application prospect in the fields of medicine,energy,biology,etc.More and more researchers are devoted to the preparation and application of porous hollow microspheres,and various synthesis methods have been explored.However,for the applications in various fields,porous hollow spheres need to meet the requirements of simple synthesis methods,low cost,and good monodispersity.For these requirements,current preparation methods have many disadvantages and deficiencies,such as poor monodispersity of porous hollow spheres,uncontrollable shape,poor reproducibility,low yield,and so on.Based on these problems,this paper presents a new type of Patchy template method to prepare porous hollow microspheres using colloidal particles with patchy structure as template.SiO₂ was selectively grown on the surface of Patchy template and porous hollow microspheres were obtained.The main research content is as follows:1.Using golf ball-like Patchy template with sulfonic groups prepared by phase separation method,SiO₂ particles synthesized by adding a cationic medium to grow SiO₂ on the surface of the Patchy template.The selectivity of Patchy template between two cationic media of cetyltrimethylammonium bromide?CTAB?and polyallylamine hydrochloride?PAH?was studied.The results show that PAH is selective for patchy template.Porous hollow SiO₂ spheres can be obtained via layer-by-layer self-assembly method.However,CTAB is not selective for patchy template and porous hollow SiO₂sphere cannot be prepared.And the selectivity reason of PAH to the Patchy template was analyzed.Then,porous Si O₂ hollow spheres with tunable size and pore diameter were synthesized by controlling the size of Patchy templates.In addition,the effect of the amount of PAH on the selectivity of Patchy template was studied,and the saturated adsorption capacity of PAH for a certain amount of Patchy templates was finally determined by designing experiment.2.Sulfonate-based spheronoid,bowl-shaped,and single-porous Patchy templates prepared by phase separation method were used to synthesize SiO₂ particles with different morphologies by adding cationic media and growing SiO₂ on the surface of Patchy templates.The effect of SiO₂ particles obtained with two cationic media of CTAB and PAH was investigated as particle emulsifier.The results show that CTAB is not selective for the Patchy template.The obtained Si O₂ particles cannot be used as particle emulsifier to stabilize the oil droplets.PAH is selective for Patchy template,and the prepared Janus particles are amphiphilic which can act as emulsifier to stabilize the oil droplets.O/W Pickering emulsion formed by n-decane and water stabilized with Janus particles was investigated.The influence of the mass fraction of Janus particles on the size of the emulsion droplets was studied.Furthermore,the Janus particles were also employed to stabilize O/W Pickering emulsion formed by paraffin wax and water.The arrangement of the Janus particles at the interface of the emulsion was examined.