Ultrahigh carrier mobility, Dirac cone and high stretchability in pyrenyl and pyrazinoquinoxaline graphdiyne/graphyne nanosheets confirmed by first-principles

TL;DR

This study uses first-principles simulations to demonstrate that novel pyrenyl and pyrazinoquinoxaline graphdiyne/graphyne nanosheets possess ultrahigh carrier mobility, high stretchability, and suitable optical properties, making them promising for nanoelectronics and energy applications.

Contribution

First-principles analysis of Pyr-GDY, PQ-GDY, and related monolayers revealing their stability, mechanical strength, optical properties, and ultrahigh carrier mobility, especially highlighting PQ-GDY's distorted Dirac cone.

Findings

Pyr-GDY and PQ-GDY nanosheets are dynamically and thermally stable.

PQ-GDY exhibits a distorted Dirac cone and anisotropic Fermi velocities.

PQ-GYN monolayer has ultrahigh carrier mobility, surpassing phosphorene and MoS2.

Abstract

Graphdiyne nanomaterials are low density and highly porous carbon-based two-dimensional (2D) materials, with outstanding application prospects for electronic and energy storage/conversion systems. In two latest scientific advances, large-area pyrenyl graphdiyne (Pyr-GDY) and pyrazinoquinoxaline graphdiyne (PQ-GDY) nanosheets have been successfully fabricated. As the first theoretical study, herein we conduct first-principles simulations to explore the stability and electronic, optical and mechanical properties of Pyr-GDY, N-Pyr-GDY, PQ-GDY and N-Pyr-GYN monolayers. We particularly examine the intrinsic properties of PQ-graphyne (PQ-GYN) and Pyr-graphyne (Pyr-GYN) monolayers. Acquired results confirm desirable dynamical and thermal stability and high mechanical strength of these novel nanosheets, owing to their strong covalent networks. We show that Pyr-based lattices can show high stretchability. Analysis of optical results also confirm the suitability of Pyr- and PQ-GDY/GYN nanosheets to adsorb in the near-IR, visible, and UV range of light. Notably, PQ-GDY is found to exhibit distorted Dirac cone and highly anisotropic fermi velocities. First-principles results reveal ultrahigh carrier mobilities along the considered nanoporous nanomembranes, particularly PQ-GYN monolayer is predicted to outperform phosphorene and MoS2. Acquired results introduce pyrenyl and pyrazinoquinoxaline graphyne/graphyne as promising candidates to design novel nanoelectronics and energy storage/conversion systems.