Department of Chemistry, University of Minnesota , 207 Pleasant Street SE, Minneapolis, Minnesota 55455, United States.
Carestream Health , 1 Imation Way, Oakdale, Minnesota 55128, United States.
ACS Nano. 2015 Dec 22;9(12):12104-14. doi: 10.1021/acsnano.5b05170. Epub 2015 Nov 30.
Potentiometric sensors, such as polymeric membrane, ion-selective electrodes (ISEs), have been used in the past to monitor a variety of chemical processes. However, the use of these sensors has traditionally been limited to aqueous solutions and moderate temperatures. Here we present an ISE with a high-capacity ion-exchange sensing membrane for measurements of nitrate and nitrite in the organic solvent propylene glycol at 150 °C. It is capable of continuously measuring under these conditions for over 180 h. We demonstrate the usefulness of this sensor by in situ monitoring of anion concentrations during the synthesis of copper and silver nanoparticles in propylene glycol using the polyol method. Ion chromatography and a colorimetric method were used to independently confirm anion concentrations measured in situ. In doing so, it was shown that in this reaction the co-ion nitrate is reduced to nitrite.
离子选择性电极（ISE）等电位传感器过去曾被用于监测各种化学过程。然而，这些传感器的使用传统上仅限于水溶液和中等温度。在这里，我们提出了一种具有高容量离子交换传感膜的 ISE，用于在 150°C 的有机溶剂丙二醇中测量硝酸盐和亚硝酸盐。它能够在这些条件下连续测量超过 180 小时。我们通过使用多元醇法在丙二醇中合成铜和银纳米粒子的原位监测阴离子浓度来证明该传感器的有用性。离子色谱法和比色法被用来独立确认原位测量的阴离子浓度。通过这样做，表明在该反应中，共离子硝酸盐被还原为亚硝酸盐。
