Growth of graphene-like films for NO2 detection

Chemical vapor deposition of graphene-like (GL) films (nano-crystalline graphite films) from methane on single crystal quartz substrates is reported. The GL films have been characterized by means of Raman spectroscopy, atomic force microscopy and electrical measurements. The thinnest GL films obtained so far have a thickness of 1.5 nm, a relatively rough surface structure and an electrical conductivity in the range of 20 kΩ/□. The high chemical sensitivity of GL films has been demonstrated by measuring the change of their conductance during exposure to a NO2-containing atmosphere. The optimal electrical conductance, high chemical sensitivity as well as the simple growth method make the GL films promising for practical applications as a chemically sensitive material.