TiO2 Nanotube Arrays: Application to Hydrogen Sensing

  • Craig A. Grimes
  • Gopal K. Mor


In this chapter we consider application of TiO2 nanotube arrays to hydrogen gas sensing. Hydrogen, a combustible, widely used industrial gas has great potential for use as a carbon-free chemical fuel. The use of hydrogen, or where hydrogen is an undesired contaminant, requires a monitor suitable for detection of meaningful concentrations. Furthermore, quantification of ppm – ppb hydrogen gas concentrations has medical relevance as an indicator of lactose intolerance [1–3], fructose malabsorption [4–8], microbial activity [9], bacterial growth [10–12], fibromyalgia [13], diabetic gastroparesis [14–16], and neonatal necrotizing enterocolitis (NEC) [17–21]. The pathogenesis of neonatal NEC results in the production of hydrogen gas, which accumulates as bubbles in the sub-mucosal area of the bowel wall [18]. Hydrogen is absorbed into the blood stream and excreted transcutaneously, as well as via the lungs into the exhaled breathe [19–21]. For monitoring of NEC in pre-term infants, it appears a clinically useful hydrogen sensor must be capable of detecting transcutaneous hydrogen at levels of approximately 25 ppm to 1 ppm, while the sensitivity of the infants’ skin requires the use of unheated sensors.


Lactose Intolerance Space Charge Layer Sensor Resistance Hydrogen Sensor Hydrogen Exposure 
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© Springer Science + Business Media, LLC 2009

Authors and Affiliations

  1. 1.Electrical Engineering DepartmentPennsylvania State UniversityUniversity ParkUSA
  2. 2.Materials Research InstitutePennsylvania State UniversityUniversity ParkUSA

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