College of Environmental and Resource Sciences, Zhejiang University, 310058 Hangzhou, China.
Key Laboratory of Water Pollution Control and Environmental Security Technology, 310058 Hangzhou, Zhejiang Province, China.
Environ Sci Technol. 2021 Oct 5;55(19):13093-13102. doi: 10.1021/acs.est.1c05363. Epub 2021 Sep 22.
Phosphate as one of the most essential components of living systems, robust analytical techniques available for phosphate sensing in natural waters and soils are essential for monitoring and predicting water quality and agronomic evaluation of phosphate. Using cyclic voltammetry, a point-of-use electrochemical sensor zirconium dioxide/zinc oxide/multiple-wall carbon nanotubes/ammonium molybdate tetrahydrate/screen printed electrode (ZrO/ZnO/MWCNTs/AMT/SPE) was applied to explore the electro-redox reaction of phosphomolybdate complexes on the surface of electrode, which produced a quantitative electrochemical response of phosphate anions. The modification of the electrode surface with ZrO/ZnO/MWCNTs nanocomposites is able to generate the electroactive species via chemical reaction between molybdenum (Mo(VI)) and the targeted phosphate anions, leading to a sensitive detection technique for trace phosphate with a lower detection limit (LOD = 2.0 × 10 mol L), higher reproducibility, anti-interference, and precision in different soil sources. This system will be of great potential to advance the trace-level understanding of phosphate especially in field environmental analysis.
磷作为生命系统中最基本的成分之一，在天然水和土壤中进行磷酸盐检测的强大分析技术对于监测和预测水质以及对磷酸盐的农学评价至关重要。本研究采用循环伏安法，应用基于氧化锆/氧化锌/多壁碳纳米管/钼酸铵四水合物/丝网印刷电极（ZrO/ZnO/MWCNTs/AMT/SPE）的现场电化学传感器，研究了电极表面上磷钼酸盐配合物的电氧化还原反应，从而产生了磷酸盐阴离子的定量电化学响应。通过钼（Mo(VI)）与目标磷酸盐阴离子之间的化学反应，在电极表面修饰 ZrO/ZnO/MWCNTs 纳米复合材料，能够产生电活性物质，从而实现对痕量磷酸盐的灵敏检测，检测下限（LOD = 2.0×10mol L）更低，重现性更高，具有抗干扰性和在不同土壤来源中的精度。该系统将极大地促进对磷的痕量水平的理解，特别是在现场环境分析中。
