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On-surface synthesis and characterization of polyynic carbon chains.

ABSTRACT: Carbyne, an elusive sp-hybridized linear carbon allotrope, has fascinated chemists and physicists for decades. Due to its high chemical reactivity and extreme instability, carbyne was much less explored in contrast to the sp²-hybridized carbon allotropes such as graphene. Herein, we report the on-surface synthesis of polyynic carbon chains by demetallization of organometallic polyynes on the Au(111) surface; the longest one observed consists of ∼60 alkyne units (120 carbon atoms). The polyynic structure of carbon chains with alternating triple and single bonds was unambiguously revealed by bond-resolved atomic force microscopy. Moreover, an atomically precise polyyne, C₁₄, was successfully produced via tip-induced dehalogenation and ring-opening of the decachloroanthracene molecule (C₁₄Cl₁₀) on a bilayer NaCl/Au(111) surface at 4.7 K, and a band gap of 5.8 eV was measured by scanning tunnelling spectroscopy, in a good agreement with the theoretical HOMO-LUMO gap (5.48 eV).

SUBMITTER: Gao W

PROVIDER: S-EPMC10896587 | biostudies-literature | 2024 Mar

REPOSITORIES: biostudies-literature

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On-surface synthesis and characterization of polyynic carbon chains.

Gao Wenze W Zheng Wei W Sun Luye L Kang Faming F Zhou Zheng Z Xu Wei W

National science review 20240122 3

Carbyne, an elusive sp-hybridized linear carbon allotrope, has fascinated chemists and physicists for decades. Due to its high chemical reactivity and extreme instability, carbyne was much less explored in contrast to the sp2-hybridized carbon allotropes such as graphene. Herein, we report the on-surface synthesis of polyynic carbon chains by demetallization of organometallic polyynes on the Au(111) surface; the longest one observed consists of ∼60 alkyne units (120 carb ...[more]

PMID: 38410826

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