A versatile in situ etching-growth strategy for synthesis of yolk–shell structured periodic mesoporous organosilica nanocomposites. Issue 56 (25th May 2016)

• Record Type: Journal Article
• Authors: Wei, Yong; Li, Xiaomin; Elzatahry, Ahmed A.; Zhang, Renyuan; Wang, Wenxing; Tang, Xueting; Yang, Jianping; Wang, Jinxiu; Al-Dahyan, Daifallah; Zhao, Dongyuan
• Is Part Of: RSC advances. Volume 6:Issue 56(2016)
• Page Start: 51470
• Page End: 51479
• Publication Date: 2016-05-25
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/c6ra08541e
• Languages: English
• ISSNs: 2046-2069

Abstract

Abstract : A versatile " in situ etching-growth" strategy has been proposed to synthesize mesoporous composites with yolk–shell structure and controlled PMO shell, by combing the etching process with the shell growth. Abstract : This paper describes a versatile in situ etching-growth strategy for the preparation of periodic mesoporous organosilica (PMO) composites with yolk–shell structure, which can generate the void space and construct the outer PMO shells at the same time. The superparamagnetic yolk–shell Fe3 O4 @PMO composites (YS-Fe3 O4 @PMO) with radical mesochannels were also synthesized with this unique in situ etching-growth strategy by using Fe3 O4 @nSiO2 nanoparticles as the initial core. This method provides a general route for the synthesis of yolk–shell structured nanomaterials with different sized void spaces, various chemical composition cores, as well as organic functional PMO shells with radical mesochannels. Moreover, we can also obtain asymmetric or asymmetric hollow Fe3 O4 @PMO materials with a cubic PMO shell. All the magnetic mesoporous composites possess very high surface areas and large pore volumes (586 m 2 g −1 and 0.52 cm 3 g −1 for YS-Fe3 O4 @PMO, 946 m 2 g −1 and 0.86 cm 3 g −1 for asymmetric hollow Fe3 O4 @PMO). Gold nanoparticles could be encapsulated and confined in the void space of YS-Fe3 O4 @PMO composites through an in situ salt impregnation. The resultant YS-Fe3 O4 @Au@PMO nanomaterials could be used to catalyze the reduction of 4-nitrophenol with an ultrahigh efficiency ( k = 0.01197 s −1 ). The magnetic catalysts could be easily recovered by a magnet and reused for more than 10 cycles with efficiency retained as high as 95%.