日本京都大学Gu Cheng团队利用扩散调节多孔材料分离水同位素。相关研究成果发表在2022年11月9日出版的《自然》。

同位素是组成上存在差异的分子实体。发现一种分离同位素的方法在根本上和技术上都是至关重要的，但仍然具有挑战性，这是由于其非常相似的物理化学性质和化学交换平衡，它们是最难分离的同位素对。

该文中，研究人员报道了在室温下通过构建两种多孔配位聚合物（PCPs，或金属-有机框架）有效分离水同位素，其中框架内的触发器分子运动提供扩散调节功能。流量由收缩孔隙上的动态闸门的局部运动调节，从而放大水同位素扩散速率的微小差异。

两种PCPs：H₂O蒸汽上都发生了显著的温度响应吸附，并优先吸附到PCPs中，与D₂O蒸汽相比，吸收显著增加，促进了H₂O/HDO/D₂O三元混合物在室温下基于动力学的蒸汽分离，H₂O分离因子约为210。

附：英文原文

Title: Separating water isotopologues using diffusion-regulatory porous materials

Author: Su, Yan, Otake, Ken-ichi, Zheng, Jia-Jia, Horike, Satoshi, Kitagawa, Susumu, Gu, Cheng

Issue&Volume: 2022-11-09

Abstract: The discovery of a method to separate isotopologues, molecular entities that differ in only isotopic composition1, is fundamentally and technologically essential but remains challenging2,3. Water isotopologues, which are very important in biological processes, industry, medical care, etc. are among the most difficult isotopologue pairs to separate because of their very similar physicochemical properties and chemical exchange equilibrium. Herein, we report efficient separation of water isotopologues at room temperature by constructing two porous coordination polymers (PCPs, or metal–organic frameworks) in which flip-flop molecular motions within the frameworks provide diffusion-regulatory functionality. Guest traffic is regulated by the local motions of dynamic gates on contracted pore apertures, thereby amplifying the slight differences in the diffusion rates of water isotopologues. Significant temperature-responsive adsorption occurs on both PCPs: H2O vapour is preferentially adsorbed into the PCPs, with substantially increased uptake compared to that of D2O vapour, facilitating kinetics-based vapour separation of H2O/HDO/D2O ternary mixtures with high H2O separation factors of around 210 at room temperature.

DOI: 10.1038/s41586-022-05310-y

Source: https://www.nature.com/articles/s41586-022-05310-y