TY - JOUR

T1 - Preparation of ZIF-62 polycrystalline and glass membranes for helium separation

AU - Zhao, Zhijun

AU - Ding, Li

AU - Mundstock, Alexander

AU - Stölting, Oliver

AU - Polarz, Sebastian

AU - Wang, Haihui

AU - Feldhoff, Armin

N1 - Funding Information: This work was financially supported by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation, project number 409987259). The authors thank L. Wagner and Prof. U. Giese for the DSC measurements, Dr. R. Almeev for access to the JSM-7610FPlus scanning electron microscope, and F. Steinbach for the technical assistance during energy-dispersive X-ray experiments.

PY - 2024/5

Y1 - 2024/5

N2 - Defects among the grains of MOF polycrystalline membranes lead to non-selective gas transport, thereby reducing their selectivity in gas separation. In this work, ZIF-62 polycrystalline membranes with a well-intergrown structure were prepared on MXene-modified supports. Subsequent thermal treatment transformed the membranes into glass membranes, effectively eliminating non-selective defects at grain boundaries. Due to the incorporation of the MXene film and the vertical positioning of the support during the solvothermal process, only a minimal portion of the glass melt infiltrated into the porous support. Across the temperature range of 303 K–423 K and pressure range of 1 bar–3 bar, the ZIF-62 glass membranes showcased superior helium separation property and long-term chemical stability (resistant to CO2 and H2O). The helium permeance reached approximately 51 GPU, with selectivities against N2 and CH4 being 17.4 and 13.9, respectively, outperforming current MOF membranes.

AB - Defects among the grains of MOF polycrystalline membranes lead to non-selective gas transport, thereby reducing their selectivity in gas separation. In this work, ZIF-62 polycrystalline membranes with a well-intergrown structure were prepared on MXene-modified supports. Subsequent thermal treatment transformed the membranes into glass membranes, effectively eliminating non-selective defects at grain boundaries. Due to the incorporation of the MXene film and the vertical positioning of the support during the solvothermal process, only a minimal portion of the glass melt infiltrated into the porous support. Across the temperature range of 303 K–423 K and pressure range of 1 bar–3 bar, the ZIF-62 glass membranes showcased superior helium separation property and long-term chemical stability (resistant to CO2 and H2O). The helium permeance reached approximately 51 GPU, with selectivities against N2 and CH4 being 17.4 and 13.9, respectively, outperforming current MOF membranes.

KW - Gas separation

KW - Helium recovery

KW - MOF glass

KW - MXene

KW - ZIF-62 membrane

UR - http://www.scopus.com/inward/record.url?scp=85188706894&partnerID=8YFLogxK

U2 - 10.1016/j.memsci.2024.122677

DO - 10.1016/j.memsci.2024.122677

M3 - Article

AN - SCOPUS:85188706894

VL - 700

JO - Journal of membrane science

JF - Journal of membrane science

SN - 0376-7388

M1 - 122677

ER -