SGER: NANOPOROUS THIN-FILM OXIDE ELECTRODES FOR PHOSPHATE SENSING

CBET-0836625M。威斯康星大学麦迪逊分校的安德森：已经证明，可以使用微孔氧化铁薄膜电极来制造磷酸盐传感器。Fe(III)还原为Fe(II)的电位是磷酸盐浓度的函数。磷酸盐在氧化铁表面的吸附改变了电极的电流-电压行为。已测量到低至10-9M和几个数量级的溶液中的磷酸盐水平。提出的假设是，铁的氧化还原峰的电位是吸附的磷酸盐及其在溶液中的形态的函数。与现场pH探头和化学平衡建模相结合，可能开发出一种独特的传感器，能够测量额外分析物的浓度和形态，如砷酸盐、硅酸盐、碳酸盐、乙酸盐等。广泛的影响：磷作为水生系统限制营养的重要性首次在1974年由迅达在安大略省实验湖地区进行的全湖施肥实验中得到证明。过量的磷会导致藻类和其他水生植物的不良生长，最终导致自然水体的富营养化。现场电化学磷酸盐传感器的开发将允许在自然水域中进行近瞬时测量，使分析更方便、更便宜。实时传感器将允许磷酸盐监测数据与瞬时天气事件同步，并将促进对磷酸盐控制战略的快速反馈。虽然有商业上可用的氮素营养传感器，但没有这样的磷酸盐传感器。这项建议满足了这一需求。在这个项目中，安德森教授和伊莎贝尔·泰杰多博士将培养一名博士生。Tejedor博士是年轻本科生和研究生的榜样，尤其是理工科女性的榜样。作为一名以西班牙语为母语的人，泰耶多博士不仅提供了作为导师的学术和实验室技能，还提供了学生在其他讲英语的人的指导下无法获得的文化和语言接触。

CBET-0836625M. Anderson, University of Wisconsin MadisonIntellectual Merrit: It has been shown that a phosphate sensor can be fabricated using a microporous iron oxide thin film electrode. The reduction potential of Fe (IIII) to Fe (II) is shown to be a function of phosphate concentration. The adsorption of phosphate to the surface of the iron oxides alters current vs. voltage behavior of the electrode. Phosphate levels in solution as low as 10-9M and several orders of magnitude have been measured. The hypothesis of the proposal is that the potential of the oxidation-reduction peak of iron is a function of phosphate adsorbed as well as its speciation in solution. Coupled with an in-situ pH probe and chemical equilibrium modeling using it may be possible to develop a unique sensor capable of measuring the concentration and speciation of additional analytes such as arsenates, silicates, carbonates, acetates, etc.Broader Impacts: The importance of phosphorus as the limiting nutrient in aquatic systems was first documented in whole lake fertilization experiments conducted by Schindler in the Ontario Experimental Lakes Area in 1974. Excess phosphorus can lead to undesired growth of algae and other aquatic vegetation, ultimately causing the eutrophication of natural water bodies. The development of an in-situ electrochemical phosphate sensor would allow for near-instantaneous measurements in natural waters, making analysis more convenient and less expensive. A real-time sensor would allow for the synchronization of phosphate monitoring data with transient weather events, and would facilitate rapid feedback for phosphate control strategies. While commercially available sensors exist for the nitrogen nutrients, no such sensor exists for phosphate. This proposal addresses this need. In this project, Prof. Anderson, and Dr. Isabel Tejedor, will train one PhD student. Dr. Tejedor serves as a role model for young undergraduate and graduate students and especially for woman in science and engineering. As a native Spanish-speaking person, Dr. Tejedor provides not only the academic and laboratory skills as a mentor but as well the cultural and language exposure that the students would otherwise not obtain working under the guidance of other English-speaking individuals.