TEM observation of aggregation steps in room-temperature silicalite-1 zeolite formation

Aggregates of nanosized crystalline units of Silicalite-1 zeolite were detected in a detailed TEM analysis of a clear solution aged for 40 months at room temperature. Inspection of the TEM images reveals the aggregation of these building units into larger crystalline zeolite particles even without heating. The smaller individual units resemble the earlier proposed nanoslab and preferentially stack along a or b crystallographic directions.

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