سنتز و مشخصه يابي نانوساختار كروي توخالي سيليس با پوسته مزوحفره و پوشش دهي آن بر سطح منسوج

The severe limitations of mesoporous materials for absorbing large molecules as well as the low speed of the absorption process have led to extensive efforts in recent years to synthesize hierarchical macro/meso/microporous materials within the structure. In this study, the synthesis of hollow mesoporous silica particles with hierarchical porous structure (micro, meso an‎d macro pores) an‎d tunable shell thickness was performed by modifying the Stöber method an‎d controlling the synthesis process, in particular by removing the surfactant. Also, in order to control the size of macropores to improve the properties of particles, especially the absorption an‎d loading of large molecules in the resulting particle structure, a new synthesis method based on the combination of the Stöber an‎d microemulsion methods was investigated, in which normal-hexane organic compound was used as the oil phase in the Stöber bath. On the other han‎d, no research has been reported on coating textiles with hollow mesoporous silica particles an‎d investigating their properties. Therefore, in this study, synthesis of silica mesoporous structure with large pores, optimization of its structure an‎d coating it on fabric were considered in order to increase the development of application of these particles, an‎d the properties an‎d performance of the fabricated textile were investigated, especially in terms of dye absorption capability. The physical, chemical an‎d pore structure properties of hollow mesoporous silica particles an‎d coated fabric samples were eva‎luated using TEM, FE-SEM, EDS spectroscopy, nitrogen adsorption-desorption tests, DLS analysis an‎d FTIR an‎d contact angle, an‎d cationic dyes were used to investigate absorption properties. Based on the results, the optimum conditions for the production of hollow mesoporous silica particles included a Stöber solution containing water/ethanol/ammonium hydroxide/TEOS with a volume ratio of 50/30/1/5 mL an‎d then aging in ethanol for 24 hours an‎d also the use of an acidic ethanol solution (ethanol/HCl with a volume ratio of 40/0.24 mL) to remove the surfactant template. The resulting sample with a uniform hierarchical porous structure an‎d particle size of 841 nm, specific surface area of 3965 m2/g an‎d total pore volume of 2.5 cm3/g had high cationic dye absorption capacity an‎d showed 82% efficiency an‎d 71 mg/g absorption capacity in 20 minutes from the start of the absorption process of 50 ppm Basic Red 18 dye. Also, increasing the stirring rate of the sample during the formation of the silica network structure, in addition to increasing the size of macropores (from 627 nm to 750 nm), increased the size of mesopores in the shell structure, an‎d consequently increased the dye absorption rate by the resulting sample. By increasing the TEOS concentration an‎d thus increasing the average shell thickness from 98 nm to 167 nm, the size of macropores an‎d mesopores decreased in the synthesized particles. Also, by increasing the storage time of silica core-shell particles in ethanol from 1 hour to 24 hours, the shell thickness of hollow silica particles increased from 167 nm to 240 nm an‎d dye absorption efficiency improved up to 2 times. Increasing the HCl concentration in the template removal solution, by swelling the shell an‎d better penetration of the removal solution into the structure, resulted in increased hydro‎philicity of the particles an‎d increased thickness an‎d size of shell mesopores. Using the combined Stöber/emulsion method increased particle size from 841 nm to 1041 nm an‎d resulted in increased dye absorption efficiency from 40% to 67% in the initial stages of the absorption process.coating stability in the sample modified with monoethanolamine.

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حسين توانايي , فرزانه علي حسيني