Enrichment of Semiconducting Single-Walled Carbon Nanotubes with Indigo-Fluorene-Based Copolymers and Their Use in Printed Thin-Film Transistors and Carbon Dioxide Gas Sensors

作者：Chang Guo, Jianying Ouyang, Homin Shin, Jianfu Ding, Zhao Li, François Lapointe, J. Lefebvre, Arnold J. Kell, Patrick R. L. Malenfant · 发表于：ACS Sensors · 年份：2020 · DOI：10.1021/acssensors.0c00764 · 被引用次数：50 · 研究领域：Carbon Nanotubes in Composites、Gas Sensing Nanomaterials and Sensors、Advanced Sensor and Energy Harvesting Materials

High-purity semiconducting single-walled carbon nanotubes (sc-SWCNTs) are promising for portable and high-sensitivity gas sensors because of their excellent physical and electrical properties. Here, we describe the synthesis of a novel indigo-fluorene-based copolymer ( PFIDBoc ) that has been designed to selectively enrich sc-SWCNTs with excellent purity (>99.9%) yet contain a latent function in the form of a tert -butoxy ( t -BOC)-protected amine that can be later revealed and exploited for carbon dioxide (CO 2 ) gas sensing. SWCNTs wrapped with the PFIDBoc polymer can be easily converted via an on-chip thermal process to reveal a vinylogous amide moiety with a secondary amine nitrogen within the indigo building block of the copolymer which is perfectly suited for CO 2 recognition. Thin-film transistors and sensors were inkjet-printed onto rigid and flexible substrates, demonstrating the versatility of enriched PFIDBoc- derived sc-SWCNT dispersions. The printed transistors exhibited a mobility up to 9 cm 2 V –1 s –1 and on/off current ratios >10 5 . We further demonstrate herein a CO 2 sensor for indoor air quality monitoring even in low humidity environments, possessing a linear response with up to ∼5.4% sensitivity and a dynamic range between 400 and 2000 ppm in air with a relative humidity of ∼ 40%.