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A facile template route to periodic mesoporous organosilicas nanospheres with tubular structure by using compressed CO₂.

ABSTRACT: Periodic mesoporous organosilicas (PMOs) nanospheres with tubular structure were prepared with compressed CO₂ using cationic and anionic mixed surfactant (CTAB/SDS) and triblock copolymer Pluronic P123 as bi-templates. TEM, N₂ adsorption-desorption, solid NMR, and FTIR were employed to characterize the obtained materials. Compressed CO₂ severed as acidic reagent to promote the hydrolysis of organosilicas, and could tune the morphology and structure of the obtained PMOs nanomaterials simple by adjusting the CO₂ pressure during the synthesis process. Rhodamine B (RB) and Ibuprofen (IBU), as the model dye and drug, were loaded into the prepared nanomaterials to reveal its adsorption and desorption ability. Furthermore, different molars of the surfactant (CTAB/SDS) and organosilane precursor (BTEB) were investigated to show the effect of the surfactant concentration on the morphology and structure of the PMOs prepared with compressed CO₂, and some different structures were obtained. A possible mechanism for the synthesis of PMOs with tubular structure using compressed CO₂ was proposed based on the experimental results.

SUBMITTER: Huang X

PROVIDER: S-EPMC5357914 | biostudies-literature |

REPOSITORIES: biostudies-literature

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