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Unusual reversibility in molecular break-up of PAHs: the case of pentacene dehydrogenation on Ir(111).

ABSTRACT: In this work, we characterize the adsorption of pentacene molecules on Ir(111) and their behaviour as a function of temperature. While room temperature adsorption preserves the molecular structure of the five benzene rings and the bonds between carbon and hydrogen atoms, we find that complete C-H molecular break up takes place between 450 K and 550 K, eventually resulting in the formation of small graphene islands at temperatures larger than 800 K. Most importantly a reversible temperature-induced dehydrogenation process is found when the system is annealed/cooled in a hydrogen atmosphere with a pressure higher than 5 × 10^-7 mbar. This novel process could have interesting implications for the synthesis of larger acenes and for the manipulation of graphene nanoribbon properties.

SUBMITTER: Curcio D

PROVIDER: S-EPMC8179676 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Magnetic anisotropy, unusual hysteresis and putative "up-up-down" magnetic structure in EuTAl4Si2 (T = Rh and Ir).

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| S-EPMC4496665 | biostudies-literature

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