open access

https://hdl.handle.net/2115/39538

Direct synthesis of MgH2 nanofibers at different hydrogen pressures

英語

Hydriding chemical vapor deposition

2009-09

Elsevier Ltd.

International Journal of Hydrogen Energy

34(17)

7283-7290

This paper describes the direct synthesis of magnesium hydride (MgH2) nanofibers by hydriding chemical vapor deposition (HCVD), in which the effect of hydrogen pressure on the production rate, the composition and the shape of products obtained were examined by using X-ray diffraction (XRD), scanning electron microscopy (SEM) and Brunauer-Emmett-Teller (BET). The XRD patterns showed that the main product in each case was MgH2; in particular, the products formed at 2, 3 and 4 MPa were highly pure. In contrast, at a hydrogen pressure of 1 MPa, unhydrided Mg was deposited along with MgH2. The SEM images also revealed orientation of the as-deposited products; higher pressures of 3 and 4 MPa caused the formation of straight and curved nanofibers, and lower ones of 1 and 2 MPa, highly curved nanofibers and nanorods with a few straight nanofibers. With pressurizing hydrogen, not only the BET specific surface areas of the products but also the production rate increased. The results also appealed that HCVD could control the shape/size of MgH2 nanofibers by changing the pressure via only a single operation.

学術雑誌論文

Accepted Manuscript

0360-3199