TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Method: The flame temperature is greater than the support surface temperature, and the support surface temperature is controlled from 20-2000 degrees C, preferably 20-350 degrees C. The flame temperature is 100-5000 degrees C, preferably 1500-3500 degrees C. The metal species-based nanoparticle comprises titanium dioxide. The nanoparticle deposition and nanoparticle sintering occurs simultaneously. Preferred components: The nanostructured metal oxide: is titanium dioxide; and comprises metal oxide particles having an average particle size of less than about 100 nm, preferably 20 nm. The film has a thickness of 10-20 mu m. The nanostructure has a short range crystalline order of 1-50 nm. In the nanostructured p/n junction solar cell, the n-type metal oxide is titanium dioxide and the p-type metal oxide is nickel oxide. The fuel stream is sodium (preferred), hydrogen and hydrocarbon compound, preferably methane. The oxidizer stream is air, ozone, oxygen (preferred), fluorine, sulfur, chlorine, bromine and iodine. The metal precursor stream further comprises an inert gas. The metal species based nanoparticle comprises a metal oxide. The metal species based nanoparticle comprises a zero valent metal. The nanostructure is of columnar or granular morphology. The metal species based nanoparticles have an average particle size of less than about 100 nm, preferably 20 nm. Two or more metal species-based nanoparticles combine to form an aggregate before deposition on the support. The nanostructure morphology is columnar having a short range crystalline order of 1-50 nm. The metal species based nanoparticles have an average particle size of 10-100 nm and the nanostructure morphology is granular. The metal species based nanoparticle comprises titanium dioxide. The metal species based nanostructured film thickness is 10 nm to 1 mm. The metal species based nanostructured film: is an optoelectrical film having a thickness of 10 nm to 20 mu m; and is a catalytic film having a thickness of 1-1000 mu m.