Amperometric sensor for nanomolar nitrous oxide analysis
Amperometric sensor for nanomolar nitrous oxide analysis
复制标题
用于纳摩尔一氧化二氮分析的电流传感器
DOI：
10.1016/j.aca.2019.12.019
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发表时间：
2020
影响因子：
6.2
通讯作者：
Revsbech, Niels Peter
中科院分区：
文献类型：
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作者：
Damgaard, Lars Riis;Kelly, Colette;Casciotti, Karen;Ward, Bess B.;Revsbech, Niels Peter
一氧化二氮是一种重要的温室气体，需要敏感的技术来研究其在接近与大气平衡的浓度（20 °C时水中9.6 nM）下在环境中的分布。在这里，我们提出了一种电化学传感器，可以量化N2O在纳摩尔范围内。传感器原理依赖于放置在测量阴极前面的前保护阴极。该阴极用于周期性地阻止N2O流向测量阴极，从而在信号中产生幅度。该信号幅度不受基线电流漂移的影响，并且可以以非常高的分辨率读取，从而使新构建的传感器的灵敏度为2 nM N2O。通过将前保护阴极放置在耗氧电解液中来防止来自氧的干扰。该传感器进行了实地测试，测量N2O剖面到120米的深度在东部热带北太平洋（ETNP）的氧气最低区墨西哥海岸。
Nitrous oxide is an important greenhouse gas and there is a need for sensitive techniques to study its distribution in the environment at concentrations near equilibrium with the atmosphere (9.6 nM in water at 20 °C). Here we present an electrochemical sensor that can quantify N2O in the nanomolar range. The sensor principle relies on a front guard cathode placed in front of the measuring cathode. This cathode is used to periodically block the flux of N2O towards the measuring cathode, thereby creating an amplitude in the signal. This signal amplitude is unaffected by drift in the baseline current and can be read at very high resolution, resulting in a sensitivity of 2 nM N2O for newly constructed sensors. Interference from oxygen is prevented by placing the front guard cathode in oxygen-consuming electrolyte. The sensor was field tested by measuring an N2O profile to a depth of 120 m in the oxygen minimum zone of the Eastern Tropical North Pacific Ocean (ETNP) off the coast of Mexico.