Macroporous Monometal Oxides

The most successful metal precursors are alkoxides of Ti and Zr, because their reactivity is easily controllable. They are liquids at room temperature and can be used without a solvent, and the metal concentration is high. After infiltration into the voids of templates, they can be solidified via a sol-gel transformation. Therefore, well-ordered macroporous crystalline TiOi and ZrOi can often be prepared. 

Metal Precursor solution Template Solidification Template removal Crystal Phase Properties and application Ref. 

Ti Ti(OiPr)4 in iPrOH PS (640 nm) coated with polyelectrolyte multilayer Air dry 

Ti TiCb (50 mM) aqueous Carboxylate-modified Anodic oxidative 

Ti02 (anatase) Pore shrinkage 20 % (SEM) Crystallite size 6-12 nm (TEM) Photocatalyst Ti02 (anatase) Solar cell 

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Table 3.3 Precursors, templates, solidifications, template removal methods, crystal phase and properties of ordered macroporous crystalline monometal oxides... 

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