An excellent universal catalyst support-mesoporous silica: Preparation, modification and applications in energy-related reactions

Abstract

As a kind of versatile, excellent catalyst carriers, mesoporous silicas (mSiO2) have been widely applied for preparing various supported catalysts with ideal catalytic properties due to their uniform and regular channels, adjustable medium pore size, big surface area, controllable wall composition, high hydrothermal stability, easy functional modification and good accessibility of larger reactant molecules. mSiO2 not only enhances the dispersity of the active phase and generates more active sites for superior catalytic activity but also improves resulted selectivity and cyclic lifespan for enhanced interaction. And high adsorption capacity of mSiO2 also increases the reactant molecule enrichment. In addition, mesoporous feature of the mSiO2 pore wall can ensure diffusion of the substrate molecules and prevent leaching of active components. Thus, related investigation and application have been rapidly growing in the past decades. In this review, the development of mesoporous silica based catalysts on preparation, modification, pore size tune and energy-related applications, especially in hydrogenation reaction, esterification reaction, hydrogen production by alkane dry reforming and alcohol steam reforming and photocatalytic water splitting, is introduced in detail and the design ideas, preparation strategies and corresponding mechanism of different composite catalysts are discussed.