Microarrayed Nanostructured Titania Thin Films Functionalized for Hydrogen Detection

Abstract

Wafer scale arrays of nanostructured titania (NST) sensing elements have been fabricated using standard microfabrication techniques. Sensing elements are on a side and formed by the oxidation of titanium thin films in aqueous hydrogen peroxide. NST elements are highly sensitive to oxygen, but only slightly sensitive to hydrogen. High sensitivity to hydrogen is achieved by modification of the sensors with platinum. A platinum salt solution is introduced to the NST sensor elements and subsequently thermally decomposed. When exposed to of hydrogen at , the functionalized devices exhibit over a one-order-of-magnitude resistance decrease with a response time of ; conversely, unmodified NST exhibit little, if any, response under the same conditions. Proposed sensing mechanisms of the NST elements are briefly discussed.