Nanoporous-Carbon Coatings for Gas-Phase Chemical Microsensors
Nanoporous-carbon (NPC) is compared directly to commonly-used polymers as a gassorbing coating material on surface acoustic wave (SAW) microsensor devices. The sensing capability of these materials is measured for volatile organic compounds (VOCs), toxic-industrial chemicals (TICs), and a chemical warfare agents (CWA) simulant. All of the coatings reversibly sorb and desorb the volatile VOC and TIC compounds, however, NPC outperforms the polymers over the range of analyte concentrations studied, especially at the lowest levels, by multiple ordersof- magnitude. Conversely, NPC has good retention properties for the semi-volatile CWA simulant tested, which while detrimental for use on a reversible SAW device, infers that NPC may be wellsuited as a preconcentrator coating for such analytes. NPC is a highly-disordered low-density carbon containing both nanopores and increased interplanar spacing between graphene sheet fragments, self-assembles using pulsed laser deposition, has no residual-stress at room temperature, is stable to 600 °C, and is chemically-inert in harsh environments. It has superior chemical and aging properties compared to the conventional polymer films used in microsensor devices.
P. VINCENZINI and E. CAPPELLI
M.P. Siegal and W.G. Yelton, "Nanoporous-Carbon Coatings for Gas-Phase Chemical Microsensors", Advances in Science and Technology, Vol. 48, pp. 161-168, 2006