Two-dimensional crystals of mesoporous silica SBA-15 nanosheets with perpendicular and open channels

A preparation of mesoporous silica SBA-15 thin sheets with perpendicular nanochannels (SBA(perpendicular to)) and open ends is reported here. At a synthesis condition of pH = 2 where the silica condensation is extremely slow, micron-sized single-crystal-like hexagonally faceted nanosheets (SBA(perpendicular to)-pH2) with aspect ratio of 10-50 were formed. The nanosheets can attach to each other in sideway to extend the thin sheet. At pH = 5, multi-domain SBA(perpendicular to)-pH5 nanosheets are formed, and stacking attachment of sheets is preferred. Vivid Moire patterns are observed in large areas of stacked silica sheets, indicating excellent structure order. (C) 2014 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution 3.0 Unported License.