  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.
