An efficient and facile method was designed to produce an acidâbase bifunctional mesoporous silica nanoreactor (MS-SO3H@MS@MS-NH2) with acid sites on the inner core, unfunctionalized silica as the neutral zone shell and basic sites on the outer shell. Such acid coreâneutral zoneâbase shell structure design resulted in excellent spatial separation of the hostile functionalities and was better than that of the coreâshell structure. The spatial order of acid sites and basic sites in the mesoporous silica nanosphere offered a designated diffusion pathway that was favorable for reaction species, while the mesoporous structure endowed the material with the confinement effect. As a result, the coreâshellâshell structured mesoporous silica nanosphere was an excellent bifunctional catalyst for one-pot cascade reaction sequences.
设计了一种高效且便捷的方法,生产出一种具有酸性、碱性双功能的介孔
二氧化硅纳米反应器(MS-SO3H@MS@MS-NH2),其内核具有酸性位点,中性区域外壳为未功能化的
二氧化硅,外壳则具有碱性位点。这种酸核-中性区-碱壳的结构设计实现了对敌对功能的优秀空间分离,优于核心-壳结构。介孔
二氧化硅纳米球中酸性位点和碱性位点的空间排列提供了有利于反应物扩散的指定通道,而介孔结构赋予材料约束效应。因此,具有核心-壳-壳结构的介孔
二氧化硅纳米球是进行一次性级联反应序列的优良双功能
催化剂。