Hydrogen-Induced Sensing Response in Pd-Capped TiZrV Alloy Thin Films

Madhuri Surya1, Arka Bikash Dey2* Amit Kumar Chawla1*, Devesh Kumar Avasthi1*

2Deutsches Elektronen-Synchrotron DESY, Notskestr. 85, 22607, Hamburg, Germany
1Applied Science Cluster, School of Advanced Engineering, UPES, Dehradun, 248007, Uttarakhand, India

Email (Corresponding author): arka.bikash.dey@desy.de, akchawla@ddn.upes.ac.in, dka4444@gmail.com 

 

Hydrogen (H₂) is regarded as a clean energy carrier with applications in fuel cells, chemical industries, and energy storage. However, its high flammability and low ignition energy necessitate highly sensitive, selective, and reliable sensors to detect hydrogen leaks at low concentrations and across a range of environmental conditions. A detailed understanding and precise control of hydrogen absorption and desorption kinetics in metal hydride systems are essential for advancing hydrogen storage and sensing technologies. In this study, we explore the hydrogen sensing behaviour of Pd–TiZrV alloy thin films fabricated via magnetron sputtering on silicon substrates. The combination of palladium’s well-known catalytic activity for hydrogen dissociation with the strong gettering properties of the TiZrV alloy provides a synergistic platform for enhanced sensing performance. The films were characterized using XRD to confirm phase formation. Hydrogen gas sensing was evaluated over range of concentrations from room temperature to 200˚C. The gas sensing characteristics of the sample were recorded using a computer-controlled gas sensing set-up using Keithley 2450 source measure unit. The Pd–TiZrV thin films exhibited rapid response and recovery times, high sensitivity, and good stability at mild heating conditions. The improved performance is attributed to the formation of a Pd-capped surface layer, which facilitates hydrogen dissociation, and the underlying TiZrV layer, which enhances hydrogen uptake and electron transfer. These findings suggest that Pd–TiZrV thin films are promising candidates for hydrogen sensing applications.