Fabrication of Nanoporous Platinum Films with Dealloying Method for Hydrogen Sensor Application

Abstract

In this research, a nanoporous platinum film is synthesized using the dealloying method. Platinum–copper (Pt–Cu) alloy films with a thickness of approximately 50 nm are prepared on glass using the magnetron-co-sputtering technique. In order to obtain nanoporous Pt, the Pt–Cu alloy films are dealloyed in 1 M nitric acid solution for different intervals. It is observed that when dealloyed in the nitric acid solution for 5 h, Cu was completely removed from the alloy, and nanoporous Pt with a regular pore structure was obtained. Then, the fabricated nanoporous Pt film is tested for hydrogen detection in the concentration range of 10 ppm and–5% hydrogen at various temperatures. The results demonstrated that the sensitivity of nanoporous Pt is about 6.5 for exposure to 1% hydrogen, and the sensing mechanism of nanoporous Pt could be explained by the surface scattering phenomenon.

Keywords

• platinum
• nanoporous
• resistive sensor
• hydrogen sensor
• co-sputtering
• dealloying method