H2O Si Molar Ratio R

Silica xerogel monoliths are the major class of sol-gel process materials and their fabrication procedures were described extensively in many reviews and papers [54-58]. The principal concepts of fabrication of silica xerogel monoliths have already been described in Section 10.2, and the effects of parameters such as metal alkoxide precursor types, type of catalyst used, H2O Si molar ratio R), steric effect of precursor ligand groups, and functionality of organically modified silanes have also been discussed. Important pioneering research on the influence of these parameters on xerogel fabrication was presented in Refs [9,59-63]. 

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