Department of Chemistry and the Institute for Soldier Nanotechnologies , Massachusetts Institute of Technology , Cambridge , Massachusetts 02139 , United States.
ACS Sens. 2018 Mar 23;3(3):569-573. doi: 10.1021/acssensors.8b00026. Epub 2018 Feb 16.
Formic acid is corrosive, and a sensitive and selective sensor could be useful in industrial, medical, and environmental settings. We present a chemiresistor for detection of formic acid composed of single-walled carbon nanotubes (CNTs) and nickel bis( ortho-diiminosemiquinonate) (1), a planar metal complex that can act as a ditopic hydrogen-bonding selector. Formic acid is detected in concentrations as low as 83 ppb. The resistance of the material decreases on exposure to formic acid, but slightly increases on exposure to acetic acid. We propose that 1 assists in partial protonation of the CNT by formic acid, but the response toward acetic acid is dominated by inter-CNT swelling. This technology establishes CNT-based chemiresistive discrimination between formic and acetic acid vapors.
甲酸具有腐蚀性，因此在工业、医疗和环境等领域，能够灵敏且选择性识别甲酸的传感器将非常有用。我们提出了一种基于单壁碳纳米管（CNTs）和镍双（邻-二亚氨基-对-亚甲基苯醌）（1）的甲酸化学电阻传感器，其中 1 是一种平面金属配合物，可以作为双位氢键选择剂。该传感器可以检测低至 83 ppb 的甲酸浓度。该材料的电阻在接触甲酸时会降低，但在接触乙酸时会略有升高。我们认为 1 有助于 CNT 部分质子化生成甲酸，但对乙酸的响应则主要由 CNT 间的膨胀引起。这项技术实现了基于 CNT 的化学电阻式对甲酸和乙酸蒸气的区分。
