ZnO hexagonal microboxes enclosed only by {0001} facets with epitaxial nanowalls

摘要

Hexagonal ZnO microboxes constructed of ZnO {0001} facets with vertical and horizontal single-crystalline nanowalls were synthesized on Si(001) via a self-assembled process by thermal chemical vapor deposition. High-resolution transmission electron microscopy images show that ZnO sheets with nanowalls on top can be assembled at 86° and 62° to each other by twinning and epitaxy, respectively. The room-temperature cathodoluminescence spectrum of the microboxes shows a strong and sharp ultraviolet emission as well as a negligible green emission. The vertical and horizontal nanowalls have potential to be applied as templates for growth of vertically and horizontally aligned nanowires for three-dimensional nanoelectronics.