There is much interest in developing electrochemical sensors for H₂S detection using room temperature ionic liquids as electrolytes. To this end, this study compared the electrochemical behavior at a Pt-microdisk electrode of H₂S in [Bmim]BF₄, [C₃OHmim]BF₄, and MEA–[C₃OHmim]BF₄ (1:6.2 M ratio) using cyclic voltammetry. In both [Bmim]BF₄ and [C₃OHmim]BF₄, the electrochemical oxidation/reduction of H₂S requires too high/low a potential (about 1.5/− 1.6 V vs. Ag/Ag⁺), and these ionic liquids are therefore unsuitable for H₂S detection. Addition of monoethanolamine (MEA) to [C₃OHmim]BF₄ significantly increases the H₂S absorption capacity through the chemical reaction between MEA and H₂S. This chemical absorption enhances the electrochemical response of H₂S, in particular generating electroactive HS⁻ ions that lead to an additional and independent anodic peak at around − 0.4 V vs Ag/Ag⁺ which is suitable for H₂S sensing. There is a good linear relationship between the peak current and H₂S content in the tested range (60–210 ppm). Moreover, electroactive ambient gases such as CO₂ and SO₂ show no response at the potentials of HS⁻ oxidation, so do not interfere with H₂S detection. Our findings reveal a new kind of ionic liquid electrolyte for the detection of H₂S gas with high sensitivity and selectivity.

开发使用室温离子液体作为电解质用于H ₂ S检测的电化学传感器引起了人们的极大兴趣。为此，本研究比较了H ₂ S在[Bmim] BF ₄，[C ₃ OHmim] BF ₄和MEA– [C ₃ OHmim] BF ₄（1：6.2 M比率）使用循环伏安法。在[Bmim] BF ₄和[C ₃ OHmim] BF _4中，H ₂ S的电化学氧化/还原都需要太高/太低的电位（相对于Ag / Ag ⁺约为1.5 /-1.6 V ），并且这些离子因此液体不适用于H₂ S检测。在[C ₃ OHmim] BF _4中添加单乙醇胺（MEA）可通过MEA与H ₂ S之间的化学反应显着提高H ₂ S的吸收容量。这种化学吸收可增强H ₂ S的电化学响应，特别是产生电活性HS ^−相对于Ag / Ag ⁺，在-0.4 V附近导致一个额外且独立的阳极峰的离子，适用于H ₂ S感测。在测试范围内（60-210 ppm），峰值电流与H ₂ S含量之间存在良好的线性关系。此外，CO ₂和SO等电活性环境气体₂示出了在HS的电位无反应^-氧化，所以不用H干涉₂小号检测。我们的发现揭示了一种新型的离子液体电解质，具有高灵敏度和高选择性，可用于检测H ₂ S气体。