Pulsed-laser deposition of nanostructured Pd/C thin films: A new entry into metal-supported catalysts for hydrogen producing reactions

Carbon-supported palladium thin films were synthesized at room temperature by KrF excimer pulsed laser deposition by using oriented pyrolytic graphite and Pd target. By changing the experimental conditions, a range of structures, from smooth to porous cluster-assembled carbon films were obtained prior to deposition of the Pd films. High amount of sp2 coordinated graphitic carbon embedded with large degree of disorder is observed in these carbon films. Surface morphology was studied by using scanning electron microscopy, while compositional analysis was performed by using energy dispersive spectroscopy. Structural analysis was performed using Raman spectroscopy and Fourier transform infrared spectroscopy. The importance of morphology and chemical structure of carbon films on their catalytic activity was investigated by using the hydrolysis of aqueous NaBH4 as a reference process. Pd/C film produced by pulsed laser deposition are here demonstrated to be a better catalyst than Pd/C powder because of the high content of sp2 bonding carbon atoms arranged into the porous and irregular surface of the carbon film.