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Cooperation of N-Heterocyclic Carbenes on a Gold Surface.

ABSTRACT: Atomically precise tailoring of interface structures is crucial for developing functional materials. We demonstrate an N-heterocyclic carbene (NHC) based molecular tool, which modifies the structure of a gold surface with atomic accuracy by the formation of gold nanorods. After adsorption on the gold surface, individual surface atoms are pulled out by the NHCs, generating single-atom surface defects and mobile NHC-Au species. Atomistic calculations reveal that these molecular "ballbots" can act as assembling tools to dislocate individual surface atoms. The predicted functionality of these carbene-based complexes is confirmed by scanning tunneling microscopy measurements. Cooperative operation of these NHC-Au species induces a step-wise formation of gold nanorods. Consequently, the surface is re-structured by a zipper-type mechanism. Our work presents a foundation to utilize molecular-based nanotools to design surface structures.

SUBMITTER: Amirjalayer S

PROVIDER: S-EPMC7702088 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature

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Cooperation of N-Heterocyclic Carbenes on a Gold Surface.

Amirjalayer Saeed S Bakker Anne A Freitag Matthias M Glorius Frank F Fuchs Harald H

Angewandte Chemie (International ed. in English) 20201004 47

Atomically precise tailoring of interface structures is crucial for developing functional materials. We demonstrate an N-heterocyclic carbene (NHC) based molecular tool, which modifies the structure of a gold surface with atomic accuracy by the formation of gold nanorods. After adsorption on the gold surface, individual surface atoms are pulled out by the NHCs, generating single-atom surface defects and mobile NHC-Au species. Atomistic calculations reveal that these molecular "ballbots" can act ...[more]

PMID: 32822093

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