Grain boundary transport and vapor sensing in α-sexithiophene

Abstract

The charge transport through an α-sexithiophene bi-crystal exposed to various gaseous agents is investigated in the temperature range from 4 to 300 K. This method allows a comparison between intragrain and grain boundary effects. The importance of grain boundaries for gas sensing applications is demonstrated. Charged trap states are formed at the grain boundaries, which lead to the change of the potential barrier at the boundary. Consequently, the charge transport properties are affected by the gas exposure. © 2001 American Institute of Physics.