Visible-light-emitting layered BC2N semiconductor

We have examined the band gap of a layered BC2N compound semiconductor. The spectroscopic measurements of scanning tunneling microscopy showed the characteristics of a semiconductor with a band gap energy of 2 eV. The valence band edge measured by x-ray photoelectron spectroscopy was 0.95 eV below the Fermi level. Photoluminescence spectra showed a peak at 2.1 eV at room temperature and 4.2 K. These results were compared with the calculated band structures, and good agreement was obtained. It was concluded that the BC2N is a semiconductor with a direct band gap which emits visible light.