Sol-Gel Synthesis of Non-Silica Monolithic Materials

Abstract

Monolithic materials have become very popular because of various applications, especially within chromatography and catalysis. Large surface areas and multimodal porosities are great advantages for these applications. New sol-gel preparation methods utilizing phase separation or nanocasting have opened the possibility for preparing materials of other oxides than silica. In this review, we present different synthesis methods for inorganic, non-silica monolithic materials. Some examples of application of the materials are also included.

Selective oxidation of cyclohexene through gold functionalized silica monolith microreactors

“…The bicontinuous "sponge like" monolith structure can be obtained under specific reaction conditions and is characterized by a "continuous mutually conjugated domains and hyperbolic interfaces". [33] SEM images in Fig. 3 show that this was successfully achieved by following the synthetic protocol described above, which can be seen to lead to a "coral like" structure seen in the Au-free monolith in Fig.…”

Preparation of monolithic aluminium titanate with well-defined macropores via a sol–gel process accompanied by phase separation

“…Moreover, compared with the monoliths composed of conventional particle-packed structure, the monoliths with cocontinuous macroporous structure display a superior performance for the applications in various kinds of fields due to the unique macrostructure [12,14]. For instance, when used as support materials, a monolithic shape provides suitable mechanical strength and the presence of interconnected macropores leads to high permeability and allows facile fluid transport [24,25].…”

A simple semi sol-gel method for preparation of alumina monoliths with hierarchical pore structures

“…Many hierarchical macro-/meso-/microporous monoliths have been developed, most of them based on silica. Less focus has been put on aluminium oxide monoliths, but some examples can be found in the literature [1,4,5]. The conventional methods for preparing alumina monoliths are either sintering or sol-gel approaches.…”