| The carbon molecular sieve microspheres(CMSm) were spherical porous carbonaceous functional materials with ultra-microporous structure. Owing to its unique pore structure, high surface area and structural stability, CMSm have been extensively applied in various fields such as adsorption/separation, storage, catalysis and electrochemistry.However, the applications of CMSm are limited due to the pore structure and morphology of CMSm is hard to control. In this work, we synthesized CMSm with controllable pore structure through in-situ polymeration and carbonization using surfactant PE6800 as template and the monomers of m-aminophenol/formaldehyde resin aqueous self-assembled structure as precursor. The pore structure, chemical structure, morphology, thermal properties and hydrogen storage properties of products before or after carbonization were characterized by modern structural analysis technology such as nitrogen adsorption analysis, Fourier transform infrared spectroscopy(FTIR), Ttransmission electron microscope(TEM), Thermogravimetric analysis(TGA), etc. The influences of in-situ assembly, polymerization conditions, carbonization technology and different pore-controlled agents on the structure of CMSm were studied. The main researches are listed as follow:1) Study on the preparation of CMSm by self assembly of organic precursor: The CMSm were prepared employing organic monomers of m-aminophenol and hexamethylenetetramine self-assembled structure as precursor and PE6800 as soft template. The influences of carbonization temperatures, heating rate, surfactant concentration and the amount of pore-forming agent on the structure of CMSm were discussed. The CMSm were characterized by nitrogen adsorption/desorption analysis, FTIR, TEM and TG. The results indicate that the template decomposes at 400?, and then the pore developed. The carbon framework generally formed above 650?.Finally, CMSm with tunable micropore volume of 0.02 cm~3/g ~0.73 cm~3/g were successfully prepared.2) Study on the control of pore structure of CMSm: The CMSm were prepared employing organic monomers of m-aminophenol and hexamethylenetetramine self-assembled structure as precursor and PE6800 as soft template. The influences of the additive amount of silica spheres, P(St-AA) on the structure of CMSm were investigated. The CMSm were characterized by nitrogen adsorption/desorption analysis and TG. The results indicate that the surface area was varied from 567.1 m~2/g to 1111.9 m~2/g, and the micropore volume ranges from 0.23 cm~3/g to 0.44 cm~3/g when different amount of silica spheres were added to the reaction system and removed with hydrofluoric acid. When different amount of P(St-AA) was added, the surface area was varied from 532.0 m~2/g to 1680.0 m~2/g and the micropore volume was in the range of 0.21 cm~3/g~0.68 cm~3/g.3) Study on hydrogen storage properties of CMSm: The CMSm were prepared using monomers of m-aminophenol/formaldehyde resin aqueous self-assembled structure as precursor. The hydrogen adsorption capacity of CMSm prepared with different carbonization temperature and PE6800 concentration was studied. The results show that the H2 adsorption quantity of CMSm were 2.13wt%, 8.04wt%, 1.82wt%, 2.74wt% when the carbonization temperature range from 950?~650? under the condition of-196?/5MPa. Under the same condition, the H2 adsorption quantity of CMSm prepared with different template concentration and carbonizaed at 950? were 19.54wt%, 10.58wt%, 2.13wt%, 5.41wt%.This work enriches the ways of controlling the pore structure and the effects of pore structure on the hydroge storage properties of CMSm were also discussed. It will provide reference to the preparation of CMSm with controllable structure and application in the field of hydrogen storage. |
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