Synthesis of γ-graphyne using dynamic covalent chemistry

REVIEWS AND HIGHLIGHTS	QUANTUM SCIENCE	MOLECULAR AND SOFT-MATTER	ULTRAFAST NANO-OPTICS AND NANOPHOTONICS	MINERALOGY AND GEOCHEMISTRY

Yiming Hu, Chenyu Wu, Qingyan Pan, Yinghua Jin, Rui Lyu, Vikina Martinez, Shaofeng Huang, Jingyi Wu, Lacey J. Wayment, Noel A. Clark, Markus B. Raschke, Yingjie Zhao, and Wei Zhang
Nature Synthesis 1, 449 (2022).
DOI PDF

Most attempts to synthesize graphynes are limited to using irreversible coupling reactions, which often result in the formation of nanometre-scale materials that lack long-range order. Here the periodically sp–sp²-hybridized carbon allotrope, γ-graphyne, was synthesized in bulk via a reversible dynamic alkyne metathesis of alkynyl-substituted benzene monomers. The balance between kinetic and thermodynamic control was managed through the simultaneous use of two different hexa-alkynyl-substituted benzenes as the comonomers to yield crystalline γ-graphyne. Additionally, the ABC staggered interlayer stacking of the graphyne was revealed using powder X-ray and electron diffraction. Finally, the folding behaviour of the few-layer graphyne was also observed on exfoliation, and showed step edges within a single graphyne flake with a height of 9 nm.