Methods of manufacturing metal oxide nanowires

A method of manufacturing metal oxide nanowires including the steps of:

• providing a metal element partially enclosing a shaped cross-section;
• heating and maintaining the metal element at a temperature from 250 to 800° C.;
• and
• exposing the metal element to oxygen and water vapor containing air stream for a predetermined time period capable of allowing formation of the metal oxide nanowires within an inner lumen portion of the metal element, wherein the oxygen and water vapor containing air stream flows in a direction substantially parallel to an outer surface of the metal element such that at least a portion of the air stream enters the inner lumen through an at least partially open portion of the metal element.

A method of manufacturing metal oxide nanowires including the steps of:

• providing a tubular element with a longitudinal direction and a lumen cross-sectional area orthogonal to the longitudinal direction, wherein the lumen cross-sectional area comprises a partially enclosed area and an opening, and wherein the tubular element comprises metal;
• heating and maintaining the tubular element;
• and
• exposing the tubular element to a wet air stream directed toward an upper region on an outer surface of the tubular element in a direction orthogonal to the lumen to form relatively uniformly aligned nanowires within the lumen.