Smart Porous 3D Macrostructures of Graphene Oxide for Selective Removal and Transformation of Contaminants from Water

超过6.5亿人，包括大量加拿大北部和土著社区，无法获得安全和清洁的水。加拿大和其他许多国家承诺，在联合国可持续发展目标框架内，到2030年消除阻碍获得安全和清洁水的障碍。因此，使用点(POU)水处理设备是偏远和人口稀少地区集中式水处理系统的替代方案，例如许多无法获得清洁水的北部和土著社区。尽管过去几年取得了进展，但POU设备仍然缺乏取代集中式水处理设施所需的效率。这项研究的范围是探索利用新型碳基纳米材料氧化石墨烯(GO)开发多功能和高效POU器件的可能性。GO自组装成类似于海绵的高度多孔的3D宏观结构(3DM)。提出的研究计划的一个主要目标是了解工艺参数对3DMS性能的关键作用，如比表面积、机械性能和表面化学。这项研究计划的另一个主要目标是改善GO 3DM的机械性能，使其能够经受住几次再生和再利用周期。各种类型的纤维素纳米晶(CNCs)将与GO纳米片结合使用，将它们自组装成杂化3DM。由此产生的机械坚固的3DM将在现实的再生和再利用场景下进行测试，并将评估它们的长期健壮性。对于再生，将研究在任何家庭中可用的简单策略，如使用弱酸(醋)。缺乏污染物选择性是GO基3DMS用于水处理的商业和大规模使用的主要障碍。3DM将使用选择性地针对令人担忧的污染物的组件进行处理，包括油和有机化合物，如药物和毒素、水性细菌、重金属以及微塑料和纳米塑料。除了选择性，这项研究计划还旨在将去除的污染物转化为危害较小的化合物。3DM将使用化学试剂进行表面功能化，这些化学试剂可以将油和有机化合物转化为更小、危害更小的分子，杀灭有害的水性细菌，并与重金属离子相互作用，将它们转化为危害较小的有机金属化合物。这项研究计划的结果将有助于加拿大土著和北方社区以及世界各地使用集中式水处理设施的有限社区公平获得安全和清洁的水。POU设备还将在灾难救援场景中得到应用，这些场景中对集中式水处理设施的访问变得受到限制。

Over 650 million people, including a large number of Canadian Northern and indigenous communities, do not have access to safe and clean water. Canada, among many other countries, has made a commitment to remove barriers against access to safe and clean water by 2030 within the United Nations Sustainable Development Goals framework. As such, point of use (POU) water treatment devices are alternatives for centralized water treatment systems in remote and sparsely populated areas, such as many of the Northern and indigenous communities that lack access to clean water. Although progress has been made in past years, POU devices still lack the required efficiency to replace centralized water treatment facilities. The scope of this research program is to investigate the possibility of using graphene oxide (GO), a novel carbon-based nanomaterial, to develop multifunctional and efficient POU devices. GO is self-assembled into highly porous 3D macrostructures (3DMs) similar to sponges. One major objective of the proposed research program is to understand the critical role of processing parameters on the properties of 3DMs such as specific surface area, mechanical properties and surface chemistry. Another major goal of this research program is to improve the mechanical properties of GO 3DMs so that they can withstand several regeneration and reuse cycles. Various types of cellulose nanocrystals (CNCs) will be used in conjunction with GO nanosheets to self-assemble them into hybrid 3DMs. The resulting mechanically robust 3DMs will be tested under realistic regeneration and reuse scenarios and their long term robustness will be evaluated. For regeneration, simple strategies available in any household such as use of weak acids (vinegar) will be investigated. Lack of contaminant selectivity is a major obstacle for commercial and large scale use of GO-based 3DMs for water treatment. 3DMs will be treated with components that selectively target contaminants of concern including oils and organic compounds such as pharmaceuticals and toxins, waterborne bacteria, heavy metals and micro- and nanoplastics. Apart from selectivity, this research program also aims to transform the removed contaminants into less harmful compounds. The 3DMs will be surface functionalized with chemical agents that convert oils and organic compounds into smaller and less harmful molecules, kill harmful waterborne bacteria, and interact with heavy metal ions to convert them into less harmful organometallic compounds. The results of this research program will help bring equity in access to safe and clean water to Canadian indigenous and Northern communities, as well as any community around the world with limited access to centralized water treatment facilities. The POU devices will also find applications in disaster relief scenarios where access to centralized water treatment facilities becomes restricted.