title: Highly Sensitive Thin-Film Field-Effect Transistor Sensor for Ammonia with the DPP-Bithiophene Conjugated Polymer Entailing Thermally Cleavable tert-Butoxy Groups in the Side Chains.
abstract: The sensing and detection of ammonia have received increasing attention in recent years because of the growing emphasis on environmental and health issues. In this paper, we report a thin-film field-effect transistor (FET)-based sensor for ammonia and other amines with remarkable high sensitivity and satisfactory selectivity by employing the DPP-bithiophene conjugated polymer pDPPBu-BT in which tert-butoxycarboxyl groups are incorporated in the side chains. This polymer thin film shows p-type semiconducting property. On the basis of TGA and FT-IR analysis, tert-butoxycarboxyl groups can be transformed into the -COOH ones by eliminating gaseous isobutylene after thermal annealing of pDPPBu-BT thin film at 240 °C. The FET with the thermally treated thin film of pDPPBu-BT displays remarkably sensitive and selective response toward ammonia and volatile amines. This can be attributed to the fact that the elimination of gaseous isobutylene accompanies the formation of nanopores with the thin film, which will facilitate the diffusion and interaction of ammonia and other amines with the semiconducting layer, leading to high sensitivity and fast response for this FET sensor. This FET sensor can detect ammonia down to 10 ppb and the interferences from other volatile analytes except amines can be negligible.
authors.affiliation: Beijing National Laboratory for Molecular Sciences, Organic Solids Laboratory, Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Yang
authors.affiliation: Beijing National Laboratory for Molecular Sciences, Organic Solids Laboratory, Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, China.
authors.forename: Guanxin
authors.initials: G
authors.lastname: Zhang
authors.affiliation: Beijing National Laboratory for Molecular Sciences, Organic Solids Laboratory, Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, China.
authors.forename: Hewei
authors.initials: H
authors.lastname: Luo
authors.affiliation: Beijing National Laboratory for Molecular Sciences, Organic Solids Laboratory, Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, China.
authors.forename: Jingjing
authors.initials: J
authors.lastname: Yao
authors.affiliation: Beijing National Laboratory for Molecular Sciences, Organic Solids Laboratory, Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, China.
authors.forename: Zitong
authors.initials: Z
authors.lastname: Liu
authors.affiliation: Beijing National Laboratory for Molecular Sciences, Organic Solids Laboratory, Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, China.
authors.forename: Deqing
authors.initials: D
authors.lastname: Zhang
keywords: ammonia sensor; conjugated polymer; diketopyrrolopyrrole; thermally cleavable groups; thin-film field-effect transistor