Catalytic and inhibitive effects of Pd and Pt decorated MWCNTs on the dehydrogenation behavior of LiAlH4

A novel catalyst was developed to modify the dehydrogenation behavior of LiAlH4 (lithium alanate). Using a chemical reduction method, Pd and Pt nano-particles were decorated on multi-walled carbon nanotubes (MWCNTs). The homogeneity and surface morphology of Pd and Pt decorated MWCNTs were examined by using transmission electron microscopy and scanning electron microscopy. The dehydrogenation behavior of LiAlH4 admixed with Pd and Pt decorated MWCNTs was investigated by thermal gravimetric analysis (TGA) and the in-situ synchrotron X-ray diffraction (XRD) technique. The TGA results revealed that the addition of Pd or Pt decorated MWCNTs would have either catalytic or inhibitive effects on the dehydrogenation of LiAlH4, which were concentration dependent. The in-situ XRD analysis confirmed the catalytic power of Pd or Pt decorated MWCNTs and the corresponding dehydrogenation reaction pathway of LiAlH4. The TGA results showed that both Pd and Pt decorated MWCNTs acted not only as a catalyst for LiAlH4, but also a hydrogen absorber.