Influence of palladium chemical structure on hydrogen sensing properties of carbonaceous–palladium thin films

In this work we investigate nanocomposite carbonaceous–palladium (C–Pd) films prepared by physical vapor deposition. Such films are promising materials for hydrogen sensor applications. This is related to the highly selective hydrogen absorption by palladium nanocrystallites. The C–Pd films obtained in various technological conditions differ in structure and electrical properties. These films were characterized by SEM, EDS and FTIR spectroscopy. FTIR spec-troscopy was used to determine the amount of palladium acetate and fullerene, incompletely decomposed during the deposition process. FTIR spectra enabled us to explain the differences in C–Pd films resistance based on palladium chemical structure. The possibility of the application of C–Pd films as active layers in hydrogen sensors was also studied. The results showed that synthesized C–Pd films containing palladium nanograins could be used for hydrogen sensing.