Structural Investigation of Amorphous Ni2B by EXAFS and XRD
نویسندگان
چکیده
The structure and thermostability of hyperfine amorphous Ni2B catalysts (HA-Ni2B) have been sttidied by EXAFS, XPD and DSC. The samples prepared by chemical reduction have been proved to be amorphous. The grain size is between 5 nm and 20 nm. A short-range order cluster is formed. The distances of Ni-B or Ni-Ni did not alter due to the change of the conditions but the coordination number of Ni is changed. The HA-Ni2B is only stable up to 140°C. Over 140"C, the crystal Ni and an intermediate formed. Finally the intermediate disappears but some B2O3 can be detected.
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