Highly sensitive hydrogen sensing properties of Pt-Pd alloy thin films on a flexible substrate

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Kılınç N.

NANO EXPRESS, vol.6, no.3, pp.1-11, 2025 (ESCI, Scopus) identifier

  • Publication Type: Article / Article
  • Volume: 6 Issue: 3
  • Publication Date: 2025
  • Doi Number: 10.1088/2632-959x/ade81d
  • Journal Name: NANO EXPRESS
  • Journal Indexes: Emerging Sources Citation Index (ESCI), Scopus, Compendex, INSPEC, Directory of Open Access Journals
  • Page Numbers: pp.1-11
  • Inonu University Affiliated: Yes

Abstract

In the present study, the thin films of platinum–palladium (Pt-Pd) alloy with various compositions are prepared on a flexible polyamide substrate by using the magnetron co-sputtering technique. The atomic Pd content in the alloy was varied from 25% to 63% and the Pt-Pd alloy film thickness was approximately 2 nm. The Pt-Pd alloy thin films were tested in a wide range of hydrogen concentrations from 10 ppm to 4% hydrogen at various temperatures between room temperature to 200 °C. The hydrogen sensing mechanism of Pt-Pd alloy thin films is dominated by Pt atoms in the alloy and could be explained by surface scattering. The highest sensor response () is received as about 8.1% for Pt50Pd50 alloy thin films during exposure to 1000 ppm hydrogen at 50 °C. The sensor response and the response time of all Pt-Pd alloy thin films decreased with rising temperature in the measurement temperature range. Another result of this study is that Pt-Pd alloy thin film sensors require oxygen in the working environment to achieve both high sensor response and full recovery. As a summary, Pt-Pd alloy thin film sensors show high sensitivity, hysteresis free, low temperature operation and selective to hydrogen.