Epitaxial Growth of Hexagonal Boron Nitride on Ir(111)
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- 作者：Fabrizio Orlando ; Rosanna Larciprete ; Paolo Lacovig ; Ilan Boscarato ; Alessandro Baraldi ; Silvano Lizzit
- 刊名：The Journal of Physical Chemistry C
- 出版年：2012
- 出版时间：January 12, 2012
- 年：2012
- 卷：116
- 期：1
- 页码：157-164
- 全文大小：500K
- 年卷期：v.116,no.1(January 12, 2012)
- ISSN：1932-7455
文摘
The formation of a hexagonal boron nitride (h-BN) layer through dissociation of borazine (B3N3H6) molecules on Ir(111) has been investigated by a combination of X-ray photoelectron spectroscopy, near-edge X-ray absorption fine structure, temperature-programmed desorption, and low-energy electron diffraction. At low temperature (T = 170 K), molecular borazine adsorption occurs with the plane of the benzene-like ring parallel to the substrate. Dehydrogenation is observed at temperatures higher than 250 K and extends up to 900 K, with a maximum H2 desorption rate around 300 K. Besides dehydrogenation, room temperature adsorption of borazine leads to the formation of atomic and molecular fragments due to the break-up of part of the BN bonds. The epitaxial growth of h-BN starts at temperature higher than 1000 K where an extended and long-range ordered layer is obtained. The presence of a corrugation in the h-BN layer with moir茅 periodicity of (13 脳 13)/(12 脳 12) BN/Ir unit cell is reflected in the double component structure of the B 1s and N 1s core level spectra.