Harnessing the Sol–Gel Process for the Assembly of Non-Silicate Mesostructured Oxide Materials

Mesostructured non-silicate oxides, with well-defined organization on the 2–50 nm size scale, may play a pivotal role in advancing vital disciplines such as catalysis, energy conversion, and biotechnology. Herein, we present selected methodologies for utilizing the sol–gel process, in conjunction with organic-directed assembly, to synthesize a variety of mesostructured oxides. The nature of the inorganic precursor is critical for this process. We discuss the development of general routes for yielding stable, nanoscopic, hydrophilic, inorganic precursors compatible with organic co-assembly. In particular, we highlight the use and characterization of organic-acid-modified transition metal oxide sol–gel precursors that allow for the synthesis and processing of designer mesostructured oxides such as titania hybrids for optical applications and porous multicomponent metal oxides useful for catalysis.