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Hollow and core/shell ZSM-5 spheres were simply synthesized through in situ transformation of mesoporous silica spheres (MSS) into MFI-type zeolite with the assistant of isopropylamine (IPA) as a structure-directing agent (SDA). IPA, with a mild structure-directing ability for the construction of MFI structure, triggered a stepwise crystallization of MSS after Al addition. First, the sphere surface was crystallized to a shell of ZSM-5 crystals. The silica and alumina species in the core condensed and crystallized to ZSM-5 thereafter, forming zeolite crystal aggregates inside the spheres. The obtained ZSM-5 spheres were highly crystalline materials and maintained the shape of pristine MSS, but exhibited a hollow and core/shell structure. The techniques of XRD, FT-IR, SEM, N 2 adsorptiondesorption, 29 Si and 27 Al MAS NMR were employed to trace the crystallization process, which allowed us to propose a ''templating and surface to core'' crystallization mechanism. This strategy may serve as an alternative way for synthesizing hollow zeolite spheres.

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SCM-14 (Sinopec Composite Material No. 14), a new stable germanosilicate zeolite with a 12×8×8-ring channel system, was synthesized using commercially available 4-pyrrolidinopyridine as organic structure-directing agents (OSDAs) in fluoride medium. The framework structure of SCM-14 was determined using rotation electron diffraction (RED), and refined against synchrotron X-ray powder diffraction (SXPD) data for both as-made and calcined materials. The framework structure of SCM-14 is closely related to that of three known zeolites: mordenite (MOR), GUS-1 (GON), and IM-16 (UOS). SCM-14 has the same projection as that of mordenite and GUS-1 when viewed along the 12-ring channels, and possesses two more straight 8-ring channels running perpendicular to the 12-ring channels. The structure of SCM-14 can be constructed by either the same layers as that of GUS-1 or the same columns as that of IM-16. Based on their structural relationship, three topologically reasonable hypothetical zeolites were predicted.

A new germanosilicate zeolite named SCM‐15 (Sinopec Composite Material No. 15), the first zeolite containing a 3‐dimensional (3D) channel system with interconnected 12‐, 12‐, and 10‐ring channels (pore sizes: 6.1×7.2, 6.1×7.4, and 5.2×5.9 Å), has been synthesized using neutral 4‐pyrrolidinopyridine as organic structure‐directing agents (OSDAs). Its structure has been determined by combining single‐crystal electron diffraction (SCED) and synchrotron powder X‐ray diffraction (SPXD) data. The unique open framework structure of SCM‐15 is related to that of FOS‐5 (BEC), ITQ‐7 (ISV), PKU‐16 (POS), ITQ‐26 (IWS), ITQ‐21, Beta polymorph B, and SU‐78B, since all these framework structures can be constructed from similar chains which are connected through shared 4‐ring or double 4‐ring (d4r) units. Based on this relation, six topologically reasonable 3D large or extra‐large pore hypothetical zeolites are predicted.

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