This presentation will focus on the synthesis, characterization, and applications of porous nano-size particles of metal oxides. Selectivity to produce desired products in catalytic reactions is the focus of our research. Several examples of the design of catalysts to drive various reactions will be discussed. These catalysts are nano-size and designed via molecular control. The role of redox chemistry in preparation and use of such catalysts will be discussed. Catalysts for selective oxidations, production of acrolein, and activation of CO2 are of current interest in our group. Novel methods of catalyst preparation such as in situ mixing nozzle microwave methods will be mentioned. Catalysts that are porous oxides and mixed metal oxides are used in these reactions. Effects of morphology and particle size on rates of reaction have been observed. Applications in adsorption, catalysis, spintronics, and others will be discussed.