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Investigation of electron-induced cross-linking of self-assembled monolayers by scanning tunneling microscopy.

ABSTRACT: Ultrathin membranes with subnanometer pores enabling molecular size-selective separation were generated on surfaces via electron-induced cross-linking of self-assembled monolayers (SAMs). The evolution of p-terphenylthiol (TPT) SAMs on Au(111) surfaces into cross-linked monolayers was observed with a scanning tunneling microscope. As the irradiation dose was increased, the cross-linked regions continued to grow and a large number of subnanometer voids appeared. Their equivalent diameter is 0.5 ± 0.2 nm and the areal density is ≈1.7 × 10¹⁷ m^-2. Supported by classical molecular dynamics simulations, we propose that these voids may correspond to free volumes inside a cross-linked monolayer.

SUBMITTER: Stohmann P

PROVIDER: S-EPMC9152271 | biostudies-literature | 2022

REPOSITORIES: biostudies-literature

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Investigation of electron-induced cross-linking of self-assembled monolayers by scanning tunneling microscopy.

Stohmann Patrick P Koch Sascha S Yang Yang Y Kaiser Christopher David CD Ehrens Julian J Schnack Jürgen J Biere Niklas N Anselmetti Dario D Gölzhäuser Armin A Zhang Xianghui X

Beilstein journal of nanotechnology 20220525

Ultrathin membranes with subnanometer pores enabling molecular size-selective separation were generated on surfaces via electron-induced cross-linking of self-assembled monolayers (SAMs). The evolution of <i>p</i>-terphenylthiol (TPT) SAMs on Au(111) surfaces into cross-linked monolayers was observed with a scanning tunneling microscope. As the irradiation dose was increased, the cross-linked regions continued to grow and a large number of subnanometer voids appeared. Their equivalent diameter i ...[more]

PMID: 35673603

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