In a recently published paper in the Journal of the American Chemical Society, Professor Howard Katz details research showcasing a polymer-dopant combination that resulted in a large number of charges per unit volume of the polymer, and a high mobility for the charges, thus leading to the potential development of a polymer with a high conductivity.

The researchers from Johns Hopkins Department of Materials Science and Engineering teamed up with the University of Virginia’s Department of Mechanical and Aerospace Engineering to showcase their research in the paper titled Modification of the Poly(bisdodecylquaterthiophene) Structure for High and Predominately Nonionic Conductivity with Matched Dopants.  The paper begins by explaining that doped polymeric semiconductors feature desirable characteristics, like low thermal conductivity, structural and compositional tunability, and the capability to be flexible and printable over large areas.

With a variety of experiments to test the polymer structure and conductivity of several conductive polymers, the team concludes that with structural modifications the PQT12-type polymer backbone can support high electrical conductivity. These findings can be transferred into the development of highly conductive films that can be used in flexible displays.

Shifting focus slightly, but staying within polymer based conductors, Dr. Katz, along with researchers from JHU’s Department of Materials Science and Engineering and Department of Environmental Health and Engineering, has published the paper Sensitive and Selective NO2 Sensing Based on Alkyl- and Alkylthio-Thiophene Polymer Conductance and Conductance Ratio Changes from Differential Chemical Doping in the journal ACS Applied Materials and Interfaces.

The paper shows that NO2 can increase the electrical conductivity of the same type of polymers (PQT12 and PQTS12).  The two polymers were able to act as sensing materials for room temperature NO2 detection. These two polymers are also able to distinguish whether the detection is due to extended exposure time, or high concentration of the gas.