In the present study, silver nanoparticles have been synthesized in new hierarchical shapes by combining a simple electrospinning technique with a novel hydrothermal treatment process. A sol gel consisting of poly(vinyl alcohol) and silver nitrate was electrospun to produce nanofiber mats that were dried under vacuum at room temperature for 24 h. The dried nanofiber mats were hydrothermally treated by a novel strategy. The treatment process relied on producing water gas (Co and H(2)) to eliminate the polymer and reduce silver nitrate to silver metal. The process was carried out by heating the dried nanofiber mates at 300 degrees C for 30 min in a suitably designed reactor in which a stream of water vapor was passed through an activated carbon bed. Physiochemical characterization analyses indicate that the proposed hydrothermal treatment process can lead to production of silver nanostructures in shapes resembling the leaves of date trees.