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The synthetic clay lucentite consists of nano-plates of silicate (SiO-M. M: Mg, Al etc) with the dimension of height to length being approximately 1:100 nm or more. The preferential, face-to-face staking of these plates leads to formation of the interlayer spaces with the average distance of 1 nm. The abilities to intercalate the spaces with polymers or delaminate (exfoliate) the stacked plates have opened up many opportunities in formation of Nanomaterials. Further treatment to cause exfoliation produces silica nano-plates, which could be used as precursor for deposition of thin films via controllable, re-stacking process or as nano-fillers in nanocomposites. We have shown that poly(acrylic acid) can be used to form aligned silica nano-plates, which have structural branches. In this talk, we present in more details the silica plate surface characterization and draw conclusions on how these branches are formed. FTIR and Mg K-edge NEXAFS analysis shows that non surface (bulk) Mg ions were not chemically involved in the poly(acrylic acid)/clay intercalation, but were substantially involved in the exfoliation resulting in the silica nano-plates. During intercalation, O K-edge NEXAFS shows that surface defects were formed which represent additional structural branches on the surface. During exfoliation, these increased significantly. Si L3,2-edge NEXAFS shows this occurred by migration of SiO4 groups within the exfoliated silica plates. |