Template-Directed Molecular Assembly on Silicon Carbide Nanomesh: Comparison Between CuPc and Pentacene

详细信息    查看全文

• 作者：Chen Shi ; Chen Wei ; Huang Han ; Gao Xingyu ; Qi Dongchen ; Wang Yuzhan ; Andrew T. S. Wee
• 刊名：ACS Nano
• 出版年：2010
• 出版时间：February 23, 2010
• 年：2010
• 卷：4
• 期：2
• 页码：849-854
• 全文大小：349K
• 年卷期：0
• ISSN：1936-086X

文摘

The template-directed assembly of two planar molecules (copper phthalocyanine (CuPc) and pentacene) on SiC nanomesh has been studied by scanning tunneling microscopy and photoelectron spectroscopy, respectively. Both molecules are trapped as single molecules in the cells of SiC nanomesh at low coverage. At high coverage, CuPc forms a highly ordered single-molecular array with identical symmetry and periodicity as the substrate, whereas pentacene forms a quasi-amorphous layer due to the random mixture of three different adsorption configurations. This difference in adsorption behavior is attributed to differences in molecular geometries. The measured changes of work functions reveal weak charge transfer between the molecules and substrate. Both molecules are preferentially adsorbed on the SiC nanomesh rather than on graphene. The CuPc single-molecular array possesses good long-range order, large area coverage, and a molecular density of over 3.0 × 10¹³ molecules/cm².