Fabrication of TiN/TiO2 Nanotube-Based Heterostructure for Hydrogen Sensing Applications
Advanced Materials Interfaces, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Basım Tarihi: 2026
- Doi Numarası: 10.1002/admi.70607
- Dergi Adı: Advanced Materials Interfaces
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Aerospace Database, Applied Science & Technology Source, Compendex, INSPEC, Directory of Open Access Journals, Materials Science & Engineering Collection (ProQuest), Technology Collection (ProQuest)
- Anahtar Kelimeler: gas sensor, heterostructure, ion beam, TiO2 nanotube, titanium nitride
- İnönü Üniversitesi Adresli: Evet
Özet
An effective room-temperature hydrogen gas sensor based on a Pd/TiN/TiO2 nanotube heterostructure is demonstrated. A novel ion beam deposition method is used to form a TiN/TiO2 heterostructure on TiO2 nanotubes formed by electrochemical anodization. Comprehensive physical characterization is performed, and x-ray photoelectron spectroscopy reveals the presence of an oxynitride component within the TiN conformal layer. Current-voltage measurements, via deposited Pd electrodes, show rectifying behavior in the TiN/TiO2 heterostructures, confirming barrier formation at the interface, while the bare TiN film displays ohmic behaviour. Upon exposure to 1% H2, a substantial current enhancement is observed, whose magnitude depends on the TiN thickness. The enhanced sensing response is attributed to catalytic H2 dissociation at the Pd electrodes and the subsequent modulation of the barrier formed at the TiN/TiO2 interface. These findings confirm that the dominant sensing mechanism originates from barrier height modulation at the interface. AC impedance spectroscopy suggests that the oxynitride interlayer enhances electronic conductivity and reduces charge recombination by creating a strong static electric field within the space charge region. The TiN/TiO2 nanotube system offers a promising platform for sensitive and reliable room-temperature hydrogen detection through advanced interfacial engineering in solid-state gas sensors.