KSEF Emerging Ideas: Interfacial Engineering of Biomass Saccharification by T. reesei enzymes

Since their discovery in 1992 by researchers at Mobil R&D Labs, mesoporous ceramic materials synthesized by surfactant templating of molecular precursors have been subjects of numerous technological advances. However, most researchers have focused almost exclusively on controlling pore characteristics (size, shape, and type of order). To develop realistic applications of these materials, it will be necessary to form mesoporous materials with tailored functionality, adsorption capabilities, and catalytic activity. To accomplish this, we propose using two methods to drive the formation of functional inorganic structures at the surface of silica pores. In the first, a mixture of surfactants will be used during materials synthesis to create isolated metals on the pore surface. One surfactant will be employed that forms a complex with transition metals. The complexed metal will be confined to the interface between the surfactant and the growing inorganic phase. The second surfactant will be used to increase the degree of ordering of the materials and to control the density of the metal on the silica surface. A systematic approach to forming ordered materials will be taken by first measuring phase diagrams in the presence or absence of transition metals, and then using silica precursors to make the final materials by "nanocasting". Preliminary experiments with glycoside surfactants mixed with cetyltrimethylammonium bromide demonstrate that ternary phase diagram of mixed surfactants in water can be used to predict the pore structure of materials produced by nanocasting. Our second approach to depositing metal oxides will be to functionalize the surface with reactive organic groups, such as amines, which induce the localized precipitation of transition metal hydroxides. The hydroxides will be calcined to create silica with a high loading of well-dispersed transition metal oxide nanoparticles. Keywords: materials, synthesis, porous, ceramics, catalysis