CRYSTALLIZATION IN ZEOLITE-A STUDIED BY ATOMIC-FORCE MICROSCOPY

Crystal growth in zeolite A has been studied by atomic force microscop y (AFM), which is a very powerful technique for imaging nanoscale surf ace features. However, imaging microcrystallites is far from trivial d ue to the difficulty in controlling their orientation-surfaces incline d to the horizontal yield distorted images in an AFM. In this study th e origin and correction of image distortion is discussed and a general method for sample preparation that can be easily adapted to any micro crystalline powder is detailed. Crystal growth in zeolite A, chosen fo r its industrial importance, is discussed in detail and is shown to oc cur via a process akin to a terrace-ledge-kink (TLK) layer mechanism.