Core-Shell Engineering of PSD@HKUST-1 With Hierarchical Channels for Accelerated SF₆/N₂ Separation

The separation of sulfur hexafluoride (SF₆) from nitrogen (N₂) is an essential challenge for semiconductor industrial gas purification due to the size similarity. While microporous adsorbents exhibit highly selective adsorption, their high-capacity results in greater mass transfer resistance, longer separation times, and increased energy consumption during regeneration. Featuring a tunable shell thickness, core-shell structured PSD@HKUST-1s were synthesized via an in -situ growth approach. Benefiting from the outer-layer gas enrichment effect, the SF₆/N₂ IAST selectivity of optimized PSD@HKUST-1-AcOH boosts to 924, which is significantly higher than that of pristine HKUST-1, with about 25% lower cost. By leveraging a thin microporous shell to retain high SF₆/N₂ selectivity while utilizing a mesoporous core to accelerate gas diffusion, PSD@HKUST-1s enable shorter separation times and demonstrate robust cyclic stability. This work highlights PSD@HKUST-1s as cost-effective, high-performance candidates for semiconductor-related SF₆/N₂ separation and demonstrates a promising strategy via core-shell design and mass transfer optimization.