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.

中文翻译：

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使用双（邻-二亚氨基半醌）镍选择器的碳纳米管甲酸传感器

甲酸具有腐蚀性，灵敏且选择性的传感器可能在工业，医疗和环境环境中有用。我们提出了一种化学电阻检测单壁碳纳米管（CNT）和镍双（组成甲酸邻-diiminosemiquinonate）（1），一平面的金属配合物可以作为双中心氢键选择器起作用。检测到的甲酸浓度低至83 ppb。材料的电阻在暴露于甲酸时降低，但在暴露于乙酸时略微增加。我们建议1有助于甲酸通过甲酸使CNT部分质子化，但对乙酸的反应主要受CNT间溶胀的影响。该技术建立了甲酸和乙酸蒸气之间基于CNT的化学鉴别。