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arXiv · 1907.03534

Direct Band Gap Semiconducting Holey Graphyne: Structure, Synthesis and Potential Applications

Xinghui Liu1·Soo Min Cho·Shiru Lin·Eunbhin Yun·Eun Hee Baek·Zhongfang Chen·Do Hyun Ryu·Hyoyoung Lee
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Abstract

Here we report two-dimensional (2D) single-crystalline holey-graphyne (HGY) created an interfacial two-solvent system through a Castro-Stephens coupling reaction from 1,3,5-tribromo-2,4,6-triethynylbenzene. HGY is a new type of 2D carbon allotrope whose structure is comprised of a pattern of six-vertex and eight-vertex rings. The carbon-carbon 2D network of HGY is alternately linked between benzene rings and sp (carbon-carbon triple bond) bonding. The ratio of the sp over sp2 bonding is 50%. It is confirmed that HGY is stable by DFT calculation. The vibrational, optic, and electric properties of HGY are investigated theoretically and experimentally. It is a p-type semiconductor that embraces a natural direct band gap (~ 1.0 eV) with high hole mobility and electron mobility at room temperature. This report is expected to help develop a new types of carbon-based semiconductor devices with high mobility.

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Xinghui Liu1, Soo Min Cho, Shiru Lin, Eunbhin Yun, Eun Hee Baek, Zhongfang Chen, Do Hyun Ryu, Hyoyoung Lee. 2019-07-08. Direct Band Gap Semiconducting Holey Graphyne: Structure, Synthesis and Potential Applications. https://arxiv.org/abs/1907.03534

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