Aqueous chloramine sensors based on molecules acting as switchable dopant sites on graphene-like carbon films

基于分子作为类石墨烯碳膜上可切换掺杂位点的水性氯胺传感器

• 批准号: 530411-2018
• 负责人: Kruse, Peter
• 金额: $ 4.37万
• 依托单位: McMaster University
• 依托单位国家: 加拿大
• 项目类别: Collaborative Research and Development Grants
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=697724
• 关键词: Aqueous; chloramine; sensors; based; molecules

Water is fundamentally important to most aspects of our existence. One of the most important monitoring parameters of drinking water quality is the level of disinfectants. If their levels are too low, microorganisms can grow in the water, which are harmful to our health. If the disinfectant levels are too high, the disinfectants themselves may be harmful, or at least unpleasant to humans. After primary disinfection at the water treatment plant is complete, disinfectant levels have to be maintained throughout the water distribution system (secondary disinfection). Chloramination is increasingly used for this purpose instead of chlorination. While its persistence is a benefit during distribution, monochloramine is harder to detect (it is odorless) and remove (it is stable) at the consumer end. For applications in health care, aqua culture, swimming pools, and in the food and beverage industry, however, complete removal of chloramines by filtration is imperative. Filter lifetime is difficult to judge just by age or water volume since it is more directly a function of filter capacity and contaminant load. Ideally, a sensor immediately after the filter could warn of breaches due to defects or exhausted capacity. Here we focus on the development of a chloramine sensor for point-of-use water filters. This work will build on a novel sensor design that our research team has recently demonstrated as effective for detecting free chlorine in drinking water. The design is based on our finding that aniline oligomers are capable of being oxidized by the free chlorine in water, thus switching on their ability to act as p-dopants for carbon nanotube films. A simple chemiresistor configuration can quantitatively detect the significant conductivity change of the nanocarbon film due to the dopant switching, and hence serve as a quantitative redox sensor across the entire relevant range. Preliminary data indicates that these sensors can also be used to detect and distinguish a variety of redox-active species. The same sensing principle can be applied to pH or other analytes by using different selectively switchable dopant molecules. Hence, we propose to develop a sensing array capable of quantitatively detecting chloramines in relevant applications for our industrial partner, 3M Canada.

水对于我们存在的大多数方面至关重要。饮用水质量的最重要监测参数之一是消毒剂的水平。如果它们的水平太低，那么微生物可能会在水中生长，这对我们的健康有害。如果消毒剂水平太高，则消毒剂本身可能有害，或者至少对人类不愉快。在水处理厂进行初次消毒后，必须在整个水分配系统（第二消毒）中维持消毒剂水平。越来越多地用于此目的而不是氯化。尽管它的持久性是在分发过程中的好处，但单氯胺很难检测到（它是无味的）并在消费者端删除（稳定）。但是，对于医疗保健，水上文化，游泳池和食品和饮料行业的应用，必须通过过滤完全去除氯胺。滤波器寿命很难仅根据年龄或水量来判断，因为它更直接地是过滤容量和污染物负载的函数。理想情况下，由于缺陷或耗尽的容量，过滤器后立即警告传感器。在这里，我们专注于开发用于使用点滤器的氯胺传感器。这项工作将以一种新型的传感器设计为基础，我们的研究团队最近证明，这对于检测饮用水中的自由氯有效。该设计基于我们的发现，即苯胺低聚物能够被水中的游离氯氧化，从而开启其充当碳纳米管膜的P型物的能力。一种简单的化学仪构型可以定量检测由于掺杂剂切换而导致的纳米碳膜的显着电导率变化，因此可以作为整个相关范围内的定量氧化还原传感器。初步数据表明，这些传感器也可以用于检测和区分各种氧化还原活性物种。相同的感应原理可以使用不同的可切换掺杂剂分子应用于pH或其他分析物。 因此，我们建议开发一个能够在我们的工业合作伙伴3M加拿大的相关应用中定量检测氯胺的传感阵列。