ZIF-8-based mixed matrix membranes are most used for selective gas separation due to their obvious molecular sieving properties. However, their application remains challenging due to their incompatibility with polymer matrix. In this study, we introduced the AZIF-8 nanoparticles synthesized via partial substitution of 2-methyl imidazole (2-Mim) ligand by 3-amino-1, 2, 4-triazole (Atz) to finely tune the aperture and increase gas separation performance of MMMs. The integration of Atz ligand significantly enhances particle dispersion and compatibility with polymer. Different ligand substitution times and loadings were applied to investigate the gas separation performance. The experimental results reveal that the Atz modified ZIF-8 (AZIF-8) blended CA MMMs with 1 wt% loading showed the high separation activity. The A