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Electrical and SERS detection of disulfide-mediated dimerization in single-molecule benzene-1,4-dithiol junctions.

ABSTRACT: We applied a combination of mechanically controllable break junction (MCBJ) and in situ surface enhanced Raman spectroscopy (SERS) methods to investigate the long-standing single-molecule conductance discrepancy of prototypical benzene-1,4-dithiol (BDT) junctions. Single-molecule conductance characterization, together with configuration analysis of the molecular junction, suggested that disulfide-mediated dimerization of BDT contributed to the low conductance feature, which was further verified by the detection of S-S bond formation through in situ SERS characterization. Control experiments demonstrated that the disulfide-mediated dimerization could be tuned via the chemical inhibitor. Our findings suggest that a combined electrical and SERS method is capable of probing chemical reactions at the single-molecule level.

SUBMITTER: Zheng J

PROVIDER: S-EPMC5994741 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature

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Electrical and SERS detection of disulfide-mediated dimerization in single-molecule benzene-1,4-dithiol junctions.

Zheng Jueting J Liu Junyang J Zhuo Yijing Y Li Ruihao R Jin Xi X Yang Yang Y Chen Zhao-Bin ZB Shi Jia J Xiao Zongyuan Z Hong Wenjing W Tian Zhong-Qun ZQ

Chemical science 20180501 22

We applied a combination of mechanically controllable break junction (MCBJ) and in situ surface enhanced Raman spectroscopy (SERS) methods to investigate the long-standing single-molecule conductance discrepancy of prototypical benzene-1,4-dithiol (BDT) junctions. Single-molecule conductance characterization, together with configuration analysis of the molecular junction, suggested that disulfide-mediated dimerization of BDT contributed to the low conductance feature, which ...[more]

PMID: 29938032

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