Construction of carbon-based two-dimensional crystalline nanostructure by chemical vapor deposition of benzene on Cu(111)

A new carbon-based two-dimensional crystalline nanostructure was discovered. The nanostructure was facilely constructed by chemical vapor deposition of benzene on Cu(111) in an ultrahigh vacuum chamber. A low temperature scanning tunneling microscopy and spectroscopy study of the nanostructure indicated that it has an orthorhombic superstructure and a semiconductor character with an energy gap of 0.8 eV. An X-ray photoelectron spectroscopy study showed that C-C(sp(2)) bonding is predominantly preserved, suggesting a framework consisting of pi-conjugated building blocks. The periodic nanostructure was found to be a surprisingly excellent template for isolating and stabilizing magnetic atoms: Co atoms deposited on it can be well dispersed and form locally ordered atomic chains with their atomic magnetism preserved. Therefore the nanostructure may be suitable for organic spintronic applications. The most likely structural model for the nanostructure is proposed with the aid of density functional theory calculations and simulations, suggesting that the 2D nanostructure may consist of polyphenylene chains interconnected by Cu adatoms.