Synthesis of Pd, Pt, and Pd–Pt Nanoparticles on Carbon Nanotubes under Hydrothermal Autoclave Conditions

Pd/CNT, Pt/CNT, and Pd–Pt/CNT composites having various metal contents were prepared via ammoniate thermolysis under autoclave conditions at 180°С, and were characterized. The morphology of the thus-manufactured items was comprehensively studied by scanning electron microscopy (SEM). Metallic palladium had particles sizes in the range within 20−120 nm, and platinum in the range within 20−150 nm. X-ray powder diffraction showed that the joint reduction of palladium(II) and platinum(II) ammine complexes on carbon nanotubes under autoclave conditions yielded a Pd–Pt solid solution phase. When Pd/CNT composites were brought in contact with hydrochloric acid solutions of H 2 PtCl 6 under hydrothermal conditions at 130°С, a Pd–Pt solid solution phase was also formed on carbon nanotubes.