Materials
All the materials were purchased from Sigma Aldrich unless otherwise stated. For the synthesis of different variations of zeolitic imidazolate frameworks (ZIF-62) the following chemicals were used: zinc nitrate hexahydrate (Zn(NO3)2·6H2O), imidazole (Im), benzimidazole (bIm), All these chemicals were used as is without further purification. The following solvents were used either for chemical synthesis, dispersing synthesised particles, or washing: methanol and N, N-dimethylformamide (DMF). All these solvents were used as is without further purification. Polymers for the synthesis of mixed matrix membranes were purchased and used directly from suppliers. 6FDA-DAM ((4,4’-Hexafluoroisopropylidene) diphthalic dianhydride (6FDA) and 2,4,6-trimethyl-1,3-diaminobenzene (DAM)) is a type of polyimide that was obtained from Akron Polymer Sytems (USA) at a molecular weight of ~370k.