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Defect Engineering: A Path toward Exceeding Perfection.

ABSTRACT: Moving to nanoscale is a path to get perfect materials with superior properties. Yet defects, such as stacking faults (SFs), are still forming during the synthesis of nanomaterials and, according to common notion, degrade the properties. Here, we demonstrate the possibility of engineering defects to, surprisingly, achieve mechanical properties beyond those of the corresponding perfect structures. We show that introducing SFs with high density increases the Young's Modulus and the critical stress under compressive loading of the nanowires above those of a perfect structure. The physics can be explained by the increase in intrinsic strain due to the presence of SFs and overlapping of the corresponding strain fields. We have used the molecular dynamics technique and considered ZnO as our model material due to its technological importance for a wide range of electromechanical applications. The results are consistent with recent experiments and propose a novel approach for the fabrication of stronger materials.

SUBMITTER: Attariani H

PROVIDER: S-EPMC6641029 | biostudies-literature | 2017 Feb

REPOSITORIES: biostudies-literature

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Defect Engineering: A Path toward Exceeding Perfection.

Attariani Hamed H Momeni Kasra K Adkins Kyle K

ACS omega 20170223 2

Moving to nanoscale is a path to get perfect materials with superior properties. Yet defects, such as stacking faults (SFs), are still forming during the synthesis of nanomaterials and, according to common notion, degrade the properties. Here, we demonstrate the possibility of engineering defects to, surprisingly, achieve mechanical properties beyond those of the corresponding perfect structures. We show that introducing SFs with high density increases the Young's Modulus and the critical stress ...[more]

PMID: 31457463

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