Kuganathan Navaratnarajah, Chroneos Alexander
Department of Materials, Imperial College London, London SW7 2AZ, UK.
Faculty of Engineering, Environment and Computing, Coventry University, Priory Street, Coventry CV1 5FB, UK.
Nanomaterials (Basel). 2019 May 30;9(6):816. doi: 10.3390/nano9060816.
Technetium (Tc) is an important long-lived radionuclide released from various activities including nuclear waste processing, nuclear accidents and atmospheric nuclear weapon testing. The removal of Tc from the environment is a challenging task, and chemical capture by stable ceramic host systems is an efficient strategy to minimise the hazard. Here we use density functional theory with dispersion correction (DFT+D) to examine the capability of the porous inorganic framework material C12A7 that can be used as a filter material in different places such as industries and nuclear power stations to encapsulate Tc in the form of atoms and dimers. The present study shows that both the stoichiometric and electride forms of C12A7 strongly encapsulate a single Tc atom. The electride form exhibits a significant enhancement in the encapsulation. Although the second Tc encapsulation is also energetically favourable in both forms, the two Tc atoms prefer to aggregate, forming a dimer.
锝（Tc）是一种重要的长寿命放射性核素，可从包括核废料处理、核事故和大气核武器试验在内的各种活动中释放出来。从环境中去除锝是一项具有挑战性的任务，而通过稳定的陶瓷主体系统进行化学捕获是将危害降至最低的有效策略。在这里，我们使用带色散校正的密度泛函理论（DFT+D）来研究多孔无机骨架材料C12A7的能力，该材料可在工业和核电站等不同场所用作过滤材料，以原子和二聚体的形式封装锝。本研究表明，C12A7的化学计量形式和电子化物形式都能强烈地封装单个锝原子。电子化物形式在封装方面表现出显著增强。尽管在两种形式中第二次封装锝在能量上也是有利的，但两个锝原子倾向于聚集形成二聚体。
