Abstract: Two groups of Mg/Nb composite films were prepared by magnetron sputtering. The effects of Nb layer thicknesses and substrate temperature of Mg/Nb composite films on the dehydrogenation temperatures were investigated. Results showed that the Nb layers with thicknesses of 1 nm and 2 nm exhibited the superior catalytic effects, which can lower the dehydrogenation temperatures to 110 ℃ and 122 ℃, respectively. Besides, the substrate temperature of 125 ℃ during sputtering presented the vastest enhancement to the dehydrogenation performance of Mg (100 nm)/Nb (1 nm) composite film. The dehydrogenation temperature could decrease to 100 ℃. Meanwhile, the relative mechanisms and the effects of Nb layer thicknesses and substrate temperatures of Mg/Nb composite thin films on their dehydrogenation temperatures were discussed.
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