title: Morphology-Driven High-Performance Polymer Transistor-based Ammonia Gas Sensor.
abstract: Developing high-performance gas sensors based on polymer field-effect transistors (PFETs) requires enhancing gas-capture abilities of polymer semiconductors without compromising their high charge carrier mobility. In this work, cohesive energies of polymer semiconductors were tuned by strategically inserting buffer layers, which resulted in dramatically different semiconductor surface morphologies. Elucidating morphological and structural properties of polymer semiconductor films in conjunction with FET studies revealed that surface morphologies containing large two-dimensional crystalline domains were optimal for achieving high surface areas and creating percolation pathways for charge carriers. Ammonia molecules with electron lone pairs adsorbed on the surface of conjugated semiconductors can serve as efficient trapping centers, which negatively shift transfer curves for p-type PFETs. Therefore, morphology optimization of polymer semiconductors enhances their gas sensing abilities toward ammonia, leading to a facile method of manufacturing high-performance gas sensors.
authors.affiliation: School of Chemical Engineering and Material Science, Chung-Ang University , Seoul 156-756, Korea.
authors.forename: Seong Hoon
authors.initials: SH
authors.lastname: Yu
authors.affiliation: School of Chemical Engineering and Material Science, Chung-Ang University , Seoul 156-756, Korea.
authors.forename: Jangwhan
authors.initials: J
authors.lastname: Cho
authors.affiliation: School of Chemical Engineering and Material Science, Chung-Ang University , Seoul 156-756, Korea.
authors.forename: Kyu Min
authors.initials: KM
authors.lastname: Sim
authors.affiliation: School of Chemical Engineering and Material Science, Chung-Ang University , Seoul 156-756, Korea.
authors.forename: Jae Un
authors.initials: JU
authors.lastname: Ha
authors.affiliation: School of Chemical Engineering and Material Science, Chung-Ang University , Seoul 156-756, Korea.
authors.forename: Dae Sung
authors.initials: DS
authors.lastname: Chung
keywords: ammonia sensor; buffer layer; field-effect transistor; high sensitivity; morphology control