  Here we report two-dimensional (2D) single-crystalline holey-graphyne (HGY)
created an interfacial two-solvent system through a Castro-Stephens coupling
reaction from 1,3,5-tribromo-2,4,6-triethynylbenzene. HGY is a new type of 2D
carbon allotrope whose structure is comprised of a pattern of six-vertex and
eight-vertex rings. The carbon-carbon 2D network of HGY is alternately linked
between benzene rings and sp (carbon-carbon triple bond) bonding. The ratio of
the sp over sp2 bonding is 50%. It is confirmed that HGY is stable by DFT
calculation. The vibrational, optic, and electric properties of HGY are
investigated theoretically and experimentally. It is a p-type semiconductor
that embraces a natural direct band gap (~ 1.0 eV) with high hole mobility and
electron mobility at room temperature. This report is expected to help develop
a new types of carbon-based semiconductor devices with high mobility.
