Three-Dimensional Analysis of Structural Defects in Block Copolymer-Assembled Body-Centered Cubic Spherical Packing

Structural defects would have great influence on the properties of materials with an ordered microstructure. Body-centered cubic (BCC) structure is one of the most common spherical packing ordered structures in nature that widely exists in different material systems. Tremendous efforts have been made to study structural defects within metal BCCs. However, knowledge about structural defects in soft matter-assembled BCC systems is still limited. Here, taking advantage of the three-dimensional reconstruction through slice-and-view scanning electron microscopy (SVSEM) of block copolymer (BCP)-assembled BCC, various kinds of structural defects within soft matter-assembled BCC have been analyzed in a three-dimensional real space. Typical defects (monovacancy, interstitials, dislocations, and twinning) and defects not commonly found in hard matter BCC (I-shaped vacancy) both exist in the BCP-assembled BCC system. The strain fields of these defects have been evaluated. Results indicate that although sharing many similar defect morphological features compared with defects in hard matter BCC, structural defects in BCP-assembled BCC also present unique features due to the malleability of the polymer system. The study presented here would enrich the knowledge about structural defects within soft matter-assembled BCC and lay the foundation for further study on the structural defect–material property relationship.