A method of forming a material structure from structural units contained within a liquid solution in a spray head is described. The liquid solution includes a solvent and a solute, the solute comprising a plurality of the structural units, the structural units including monomer units, oligomer units, or combinations thereof. The method comprises forming droplets of the liquid solution including the structural units, and spraying the droplets on a substrate, thereby substantially increasing the reactivity of the structural units within the droplets relative to the structural units within the liquid solution in the spray head. The increase in reactivity can result from the droplets containing an excess of a particular ion, the ion excess resulting from a voltage applied to conductive walls of the device which dispenses the droplets. The material structure is then formed on the substrate from the more highly reactive structural units within the droplets.