Particle Technology Laboratory, Department of Mechanical and Process Engineering, ETH Zurich, CH-8092 Zurich, Switzerland.
Particle Technology Laboratory, Department of Mechanical and Process Engineering, ETH Zurich, CH-8092 Zurich, Switzerland.
J Hazard Mater. 2020 Nov 15;399:123052. doi: 10.1016/j.jhazmat.2020.123052. Epub 2020 May 28.
Formaldehyde is a carcinogenic indoor air pollutant emitted from wood-based furniture, building materials, paints and textiles. Yet, no low-cost sensor exists for on-site monitoring to fulfill stringent current and upcoming (e.g., 8 parts-per-billion by volume, ppb, in France by 2023) exposure guidelines. Here, we present an inexpensive and handheld formaldehyde detector with proven performance in real indoor air. Selectivity is achieved by a compact packed bed column of nanoporous polymer sorbent that separates formaldehyde from interferants present in ambient air. Downstream, a highly sensitive nanoparticle-based chemoresistive Pd-doped SnO sensor detects formaldehyde in the relevant concentration range down to 5 ppb within 2 min. As a proof-of-concept, we measured formaldehyde in indoor air and from different wood product emissions, in excellent agreement (R > 0.98) with high-resolution proton-transfer-reaction time-of-flight mass spectrometry. This detector is simple-in-use and readily applicable for on-site formaldehyde exposure monitoring at home or work. It is promising for internet-of-things (IOT) sensing networks or even wearables for personal exposure assessment.
甲醛是一种致癌的室内空气污染物，会从木质家具、建筑材料、油漆和纺织品中释放出来。然而，目前还没有低成本的传感器可以用于现场监测，以满足严格的现行和即将出台的（例如，到 2023 年，法国每体积 8 部分/十亿，ppb）暴露标准。在这里，我们提出了一种廉价的手持式甲醛探测器，该探测器在实际室内空气中具有经过验证的性能。通过紧凑的纳米多孔聚合物吸附剂填充床柱实现选择性，该吸附剂可将甲醛与环境空气中存在的干扰物分离。在下游，高度灵敏的基于纳米颗粒的电阻式 Pd 掺杂 SnO 传感器可在 2 分钟内检测到相关浓度范围内低至 5 ppb 的甲醛。作为概念验证，我们在室内空气中以及不同的木制品排放物中测量了甲醛，与高分辨率质子转移反应飞行时间质谱法的测量结果非常吻合（R>0.98）。该探测器使用简单，可在家中或工作场所现场用于甲醛暴露监测。它有望用于物联网（IoT）感测网络，甚至用于个人暴露评估的可穿戴设备。
