A method of making a thin film is disclosed. A solution is dispensed on a substrate. The solution is spread into a thin layer with a hydrophilic material. The substrate or the hydrophilic material is moved relative to the other. In one embodiment, a thin film grows on the substrate by chemical reaction with the solution. In an alternative embodiment, the solution is evaporated, leaving behind a particulate film.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
 The invention was made with Government support under Contract DE-AC-05-RL01830, awarded by the U.S. Department of Energy. The Government has certain rights in the invention.