alkoxides will react and polymerize to form a gel as polymerization and crosslinking proceeds viscosity increases and the material can eventually set to a rigid u201c gel u201d the u201c gel u201d consists of a crosslinked network of the desired material which incorporates the original solvent within its open porous structure the u201c gel u201d may then be dried typically by either simple heating in a flow of dry air to produce an aerogel or the entrapped solvent may be removed by displacement with a supercritical fluid such as liquid co 2 to produce an aerogel as described below final calcination of these dried materials to elevated temperatures gt 200 u00b0 c results in products which typically have very porous structures and concomitantly high surface areas depending on the alkoxide system and the water alkoxide ratios used a discernible gel point can be reached immediately or hours later the molar ratio of the total water added including water present in aqueous solutions can vary according to the specific inorganic alkoxide being reacted generally a molar ratio of water to alkoxide within the broad range of 3 to 150 is within the scope of this invention it is understood that the order of addition of the various solutions can be reversed the addition of acidic or basic reagents to the gellation reaction can have an effect on the kinetics of the hydrolysis and condensation reactions and the microstructure of the oxide hydroxide matrices derived from the alkoxide precursor which entraps or incorporates the soluble metal reagents generally a ph range of 1 12 can be used with a ph range of 1 6 preferred for these experiments after reaction the catalytic.