Graphene quantum dots with Stone-Wales defect as a topologically tunable platform for visible-light harvesting

Abstract

In this work, we report for the first time the crucial role of topological anomalies like Stone-Wales (SW) type bond rotations in tuning the optical properties of graphene quantum dots (GQDs). By means of first-principles calculations, we first show that the structural stability of GQDs strongly depends on position of SW defects. Optical absorption spectra is then computed using electron-correlated methodology to demonstrate that SW type reconstruction is responsible for the appearance of new defect-induced peaks below the optical gap and dramatically modifies the optical absorption profile. In addition, our investigations signify that electron correlation effects become more dominant for SW-defected GQDs. We finally establish that the introduction of SW defects at specific locations strongly enhances light absorption in visible range, which is of prime importance for designing light harvesting, photocatalytic and optoelectronic devices.

19 pages, 4 figures (included), accepted in Physical Review B

References in corpus (6)

• Self-passivating edge reconstructions of graphene
• Structure, Stability, Edge States and Aromaticity of Graphene Ribbons
• From Graphene constrictions to single carbon chains
• Anisotropy of the Stone-Wales Defect and Warping of Graphene Nano-ribbons: A First-principles Analysis
• Graphene flakes with defective edge terminations: Universal and topological aspects, and one-dimensional quantum behavior
• Tunable Optoelectronic Properties of Triply-Bonded Carbon Molecules with Linear and Graphyne Substructures

Cited by in corpus (2)

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