Metal-organic framework composites for nuclear waste clean-up

诸如99 Tc（锝）的长寿命环境移动放射性核素造成了严重的地下水污染问题，并且对诸如塞拉菲尔德的核场地的清理提出了严峻的挑战。这可以通过使用配置为可渗透反应屏障（PRB）材料的固相吸附剂来解决，该材料对占主导地位的99 TcO 4-阴离子具有高选择性，从而将其从受污染的地下水中捕获。在最近建立的南安普顿化学和国家海洋学中心南安普顿（NOCS）之间的多学科项目中，我们正在研究被称为金属有机框架（MOFs）的微孔材料作为PRB去除锝的潜力。MOFs是基于金属离子和有机连接剂的连接的高表面积多孔固体，并构成模块化材料平台，确保它们具有高度可调的结构和功能，以优化其特定应用的性能。在这个项目中，你将准备和测试一系列新的和现有的MOFs，并直接评估它们的锝吸收特性，预计将研究一些锝吸收机制。为了增加其作为PRB的实际效用，性能最好的MOF将被配置为复合材料，例如被污染的地下水可以流过的膜和柱。成功的候选人将在化学和NOCS方面花费时间，并将在与核工业相关的材料合成和表征以及分析方法方面发展广泛的技能。

Long-lived environmentally-mobile radionuclides such as 99Tc (technetium) pose a significant groundwater contamination issue and present a serious challenge for the clean-up of nuclear sites such as Sellafield. This can be addressed using solid-phase adsorbents configured as permeable reactive barrier (PRB) materials that have high selectivity for the dominant 99TcO4- anion, trapping this from contaminated groundwaters. In a recently established multi-disciplinary project between Southampton chemistry and the National Oceanography Centre Southampton (NOCS) we are investigating the potential of microporous materials known as metal-organic frameworks (MOFs) as PRBs for technetium removal. MOFs are high surface area porous solids based on the linking of metal-ions and organic linkers and constitute a modular materials platform ensuring they have highly tuneable structures and functionality for the optimisation of their properties for given applications. In this project you will prepare and characterise a range of new and existing MOFs and directly evaluate their technetium uptake properties, and it is expected that a number of technetium uptake mechanisms will be investigated. In order to increase their practical utility as PRBs the best performing MOFs will be configured as composite materials such as membranes and columns through which contaminated groundwater can flow. The successful candidate will spend time in both chemistry and NOCS and will develop broad skills in materials synthesis and characterisation and analytical methods relevant to the nuclear industry.