Construction And Application Of Functional Materials With Engineered Microspherical Structure From Pickering Droplets

Hierarchical superstructures that built from primary nanoscale objects and featured with a micro-or macroscopic architecture are highly desired in various applications,including adsorption,catalysis,sensing et al,credited by their synergistically integrated specialties,like rich porosity,high surface area and fast mass diffusion,excellent mechanical properties and easy operation.For synthesizing such materials,a variety of methods have been developed,such as three-dimensional printing,colloidal assembly,microfluidic,spray drying and so on.Nevertheless,most of these preparation methods face some intrinsic shortcomings and challenges,such as the necessity for specific devices,complicated operations,and the difficulty in engineering morphology or structure of materials.Herein,this paper focused on constructing functional microsphere materials with engineered structures from Pickering droplets,and exploring their properties and applications.The main research results are listed as follows:(1)Hierarchically pomegranate-like mesoporous carbon microspheres were prepared by the combination of Pickering droplet confined nano-structure assembly and surfactant induced interface growth of phenolic resin.The obtained material possesses a unique nano-to-micro multilevel complex structure,which is composed of micrometer sized spheres(70±40?m)at the macroscopic level,while constituted by a mesoporous shell layer and a large number of hollow nano-carbon spheres(about 200 nm).Such a material effectively combines the advantages of both nano and micron carbons,including high BET surface area(647.3 m²/g)and large pore volume(0.584cm³/g),excellent mechanical stability and easy separation.Moreover,we found that the thickness of outer shell and interior structure of the microspheres could be finely engineered by tuning the synthesis parameters.These microspherical materials showed high adsorption capacity and stability(13cycles)in organic pollutants adsorption,and could also be utilized as efficient support of Ru nanoparticles to enhance the catalytic performance(conversion>99%,selectivity>99%)and cycle stability(>8 cycles)in hydrogenation of aromatic compounds.(2)Polymeric ionic liquid microspheres were prepared by the polymerization of imidazolyl ionic liquid monomers within Pickering droplets.The size of these materials was about 20±10?m,and their interior structure could be engineered by tuning the synthesis parameters.Meanwhile,such synthesis method exhibited good universality and could be used to prepare other polymeric ionic liquid microspheres by using different polymerization monomers.The obtained polymeric ionic liquid microspheres showed good catalytic activity(conversion?90%,selectivity>99%)and cycle stability(>10 times)in cycloaddition reaction of CO₂ with epichlorohydrin,and could be expanded for the cycloaddition reaction of a variety of epoxy compounds.