Discovery of highly radon-selective metal-organic frameworks through high-throughput computational screening and experimental validation

Abstract

A highly radon (Rn)-selective adsorbent is essential for the capture of radon from indoor air. Here, an aluminum-based metal–organic framework (MOF), Al-NDC, was identified as a highly Rn-selective adsorbent via high-throughput screening of 4,951 MOFs in the Computation-Ready, Experimental (CoRE) MOF database. Notably, Al-NDC experimentally demonstrated an excellent Rn removal rate (52 %) – more than twice that of the activated carbon benchmarks (25 %) – while also exhibiting excellent hydrothermal, chemical, and radioactive stabilities. Moreover, useful structure–property relationships were obtained from large-scale simulations. High crystal densities, low surface areas, small pore volumes, and small diameters of the largest cavity were found to favor the selective capture of radon. Interestingly, channel-like pores of a size appropriate to fit one to two radon molecules (4.9–9.8 Å) were found to be most effective for selective radon capture. These findings provide key insights for the future development of Rn adsorbents.