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arXiv · 2409.07329

A 2D T-carbon 2-(111) structure with tunable electric and optical properties via chemical decorations: a first-principles investigation

Haifang Cai·Zhiwen Duan·Douglas S. Galvao·Kun Cai
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Abstract

We proposed a new two-dimensional carbon material named 2-(111) planar T-carbon, which is obtained by slicing bulk T-carbon along its (111) crystallographic direction. 2-(111) planar T-carbon's optical and electrical properties can be engineered via surface decoration. Comparing the DFT phonon spectra of pristine and five decorated 2-(111) planar T-carbon obtained by first-principles calculations, we conclude that surface decoration presents a promising, effective, and feasible strategy to improve the structural stability of 2-(111) planar T-carbon. The calculated band structures and electronic properties show direct electronic band gap values between 0.17 eV (-O= decorated) and 2.21 eV (Hydrogenated). Chemical decoration also promises blue or red energy shifts in its optical properties.

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Haifang Cai, Zhiwen Duan, Douglas S. Galvao, Kun Cai. 2024-09-11. A 2D T-carbon 2-(111) structure with tunable electric and optical properties via chemical decorations: a first-principles investigation. https://arxiv.org/abs/2409.07329

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