| In this article we mainly investigated the syntheses of inorganic mesoporous materials in the polyol system(polyethylene glycol-PEG).The formation mechanism was discussed based on the experiment results,and a formation mechanism was proposed:inorganic particles formed first and then aggregated to form the mesostructures.In the same system several kinds of inorganic mesoporous materials formed,which conformed that this route can be a general route for the synthesis of inorganic mesoporous materials.This article consists of three chapters,chapter one to three:In chapter one,we introduced four parts of content,mainly introduced the related information of the mesoporous materials.In the first part,we simply introduced the discovery and the concept of the mesoporous materials,and the properties compared with the traditional porous materials.The second part is the main part of chapter one. In this part,we introduced the basic synthesis process for the mesoporous materials, the prepare methods for the mesoporous materials(the method based on the inorganic templates and the method based on the organic templates),several common formation mechanisms for the mesoporous materials(liquid crystal template mechanism,cooperative formation mechanism and the formation mechanisms for the non-siliceous mesoporous materials),and the factors that influence the pore diameters.In the third part,we mainly introduced some important applications of the mesoporous materials.In the last part,we described the objective of this study.In chapter two,the template-free syntheses of mesoporous metal oxides and sulfides were introduced.Using diethylene glycol as solvent and the inorganic metal salts as metal sources,one step solvothermal processes were taken to prepare crystalline mesoporous SnO2,TiO2,ZrO2,ZnO,In2O3,ZnS and In2S3.N2 adsoption-desorption analysis proved that the materials were mesoporous in nature with relatively large specific surface areas and relatively narrow pore size distributions.Based on kinds of analysis,the formation process of the mesoporous materials in this synthesis route was as below:inorganic nanoparticles were initially formed and then aggregated to lower the surface energy,the existence of the DEG molecules prevented the nanopaticles from densely aggregating and mesopores formed.It was discovered that the morphologies of the nanoparticles for different materials varied,corresponding to different structures and morphologies of the resulting mesopores.The results from the observation of the electron microscope and the analysis from the N2 adsorption-desorption coincided.PEG with different molecule weights(TEG,PEG200,PEG400,PEG600) was used as solvent to synthesize SnO2.Based on the N2 adsorption-desorption analysis,mesoporous SnO2 formed in all these solvents,and all the SnO2 samples showed large specific surface areas,which conformed that this route using polyols as solvents and structure-directing agents can be a general route for the preparation of inorganic mesoporous materials.In chapter three,we described the synthesis and characterization of rose-flower-like mesoporousα-Ni(OH)2 and NiO.In this one-step solvothermal process,DEG was used as solvent and Ni(CH3COO)2·4H2O as reagent,rose-flower-likeα-Ni(OH)2 were formed.After calcination at 420℃for 5h,rose-flower-like NiO similar to the originalα-Ni(OH)2 formed.According to the observation from electron microscope images,the rose-flower-likeα-Ni(OH)2 were composed of nanoplates,the edges of which crinkled in some areas.And the nanopaltes of the NiO sample were not continuous,nanopores appeared.N2 adsorption-desorption analyses indicated that both the rose-flower-likeα-Ni(OH)2 and NiO were mesoporous in nature,and had relatively large specific surface areas.We also investigated the removal of acid fuchsine from aqueous solution in presence of the prepared NiO.It was discovered that the mesoporous NiO could both adsorb and decompose the acid fuchsine,the removal ability was better than P25 under the same conditions. |
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