Correlating Growth Habit of Boron-Rich Low-Dimensional Materials with Defect Structures by Electron Microscopy

Abstract

Boron carbide and boron suboxide low-dimensional materials with α-rhombohedral symmetry, here simply referred to as boron-rich nanomaterials, exhibit a variety of growth habits, including rodlike fibers, slablike platelets, and some intermediary structures, as confirmed by scanning electron microscopy (SEM) observation. The defect structures of these variants have been thoroughly characterized by advanced transmission electron microscopy techniques, which reveal the prevalence of two basic contact twinning: parallel twinning and cyclic twinning. The growth habits and defect structures of boron-rich materials are found to be strongly correlated. This has been summarized by a growth habit map, which allows us to establish a quick strategy for the determination of defect structures by simple SEM shots in boron-rich materials, alleviating ceramists from the need and complexity in the identification of multitwinned structures.