Electrochemical Interaction of Nano-Cerium Oxide Composites with Hydroxyl Radicals

自由基是由各种来源如生物代谢和大气反应产生的极其反应性和不稳定的化学物质。人体内自由基（如羟基自由基）的过度产生被认为是加速衰老、癌症、阿尔茨海默病和多发性硬化症的原因之一。因此，快速有效地检测自由基对于预防和治疗这些疾病至关重要。有几种方法已被用于检测自由基;然而，它们中的大多数在识别自由基的类型和浓度方面不够准确和一致。本提案的目标是制作一个强大的和可重复使用的羟基自由基传感器。该传感器被认为不仅对医疗诊断非常有益，而且对燃料电池和环境监测也非常有益。这项研究将由一个多元化的团队进行，他们对增加科学中代表性不足的群体的参与感兴趣（包括俄亥俄州的农村社区，WISDOM，拉丁美洲青年峰会和EXCEL计划）。拟议的研究调查羟基自由基和纳米复合材料的电化学特性，包括在纳米级的氧化还原反应机制，以及催化剂和材料结构对电子转移速率和氧化还原反应机理的影响。利用PI？利用传感器和纳米材料受控合成方面的经验，该项目力求实现以下具体目标：（1）研究基底类型和电化学催化剂对氧化铈与OH自由基之间的氧化还原反应的影响，（2）研究复合物组成对氧化铈对羟基自由基的亲和力的影响，（3）选择性地将氧化铈纳米岛存款到负载的金属纳米颗粒上以增加表面积，和（4）研究复合物对来自其它自由基类型的羟基自由基的选择性。这项研究不仅有可能改变传感器领域，还可能改变其他研究领域，包括自由基研究、纳米金属合成、复合材料合成和材料表征。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Free radicals are extremely reactive and unstable chemicals generated from various sources like biological metabolism and atmospheric reactions. Overproduction of free radicals, such as hydroxyl radicals, in a human body, is known as one of the causes for accelerated aging, cancer, Alzheimer's disease and multiple sclerosis. Therefore, a rapid and efficient detection of free radicals is essential for the prevention and cure of these diseases. Several methods have been used for the detection of free radicals; however, most of them are not accurate and consistent enough in identifying the type and concentration of free radicals. The goal of this proposal is to make a robust and reusable sensor for hydroxyl radicals. The sensor is regarded as greatly beneficial not only for medical diagnosis, but also for fuel cells, and environmental monitoring. This research will be performed by a diverse team with a strong interest in increasing the participation of underrepresented groups in science (including Ohio's rural communities, WISDOM, Latino Youth Summit, and EXCEL programs).The proposed research investigates the electrochemical characteristics of hydroxyl radicals and the nano-composites including redox reaction mechanisms at the nanoscale, and the effects of catalyst and structure of the materials on the electron transfer rate and redox reaction mechanisms. Leveraging the PIs? experience in sensors and controlled synthesis of nanomaterials, this project seeks to achieve the following specific objectives: (1) investigate the influence of the type of substrate and the electrochemical catalyst on the redox reaction between cerium oxide and OH radicals, (2) investigate the effect of the composite composition on the affinity of cerium oxide toward hydroxyl radicals, (3) selectively deposit cerium oxide nano-islands onto supported metal nanoparticles for increased surface area, and (4) investigate the selectivity of the composites toward hydroxyl radicals from other radical types. This research has the potential to transform not only the sensors field, but also other research areas including free radical studies, nano-metal synthesis, composite materials synthesis, and material characterization.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.