In this article, we report on the characterization of various molecular junctions' current-voltage characteristics (Ⅰ-Ⅴ curves) evolution under mechanical modulations, by employing a novel electrochemically assis...In this article, we report on the characterization of various molecular junctions' current-voltage characteristics (Ⅰ-Ⅴ curves) evolution under mechanical modulations, by employing a novel electrochemically assisted-mechanically controllable break junction (EC-MCBJ) method. For 1,4-benzenedithiol, the Ⅰ-Ⅴ curves measured at constant electrode pair separation show excellent reproducibility, indicating the feasibility of our EC-MCBJ method for fabricating molecular junctions. For ferrocene-bisvinylphenylmethyl dithiol (Fc-VPM), an anomalous type of Ⅰ-Ⅴ curve was observed by the particular control over the stepping motor. This phenomenon is rationalized assuming a model of atomic contact evolution with the presence of molecular junctions. To test this hypothesized model, a molecule with a longer length, 1,3-butadiyne-linked dinuclear ruthenium(H) complex (Ru-1), was implemented, and the Ⅰ-Ⅴ curve evolution was investigated under similar circumstances. Compared with Fc-VPM, the observed Ⅰ-Ⅴ curves show close analogy and minor differences, and both of them fit the hypothesized model well.展开更多
基金This work was supported by the National Basic Research Program of China (Nos. 2011YQ030124, 2014CB845603, and 2015CB932301), National Natural Science Foundation of China (Nos. 91427304, 21321062, 21303114, 21403181, and 21503179), Natural Science Foundation of Fujian Province (No. 2012J05034), and by CNRS UMR 8640 PASTEUR and LIA CNRS NanoBioCatEchem.
文摘In this article, we report on the characterization of various molecular junctions' current-voltage characteristics (Ⅰ-Ⅴ curves) evolution under mechanical modulations, by employing a novel electrochemically assisted-mechanically controllable break junction (EC-MCBJ) method. For 1,4-benzenedithiol, the Ⅰ-Ⅴ curves measured at constant electrode pair separation show excellent reproducibility, indicating the feasibility of our EC-MCBJ method for fabricating molecular junctions. For ferrocene-bisvinylphenylmethyl dithiol (Fc-VPM), an anomalous type of Ⅰ-Ⅴ curve was observed by the particular control over the stepping motor. This phenomenon is rationalized assuming a model of atomic contact evolution with the presence of molecular junctions. To test this hypothesized model, a molecule with a longer length, 1,3-butadiyne-linked dinuclear ruthenium(H) complex (Ru-1), was implemented, and the Ⅰ-Ⅴ curve evolution was investigated under similar circumstances. Compared with Fc-VPM, the observed Ⅰ-Ⅴ curves show close analogy and minor differences, and both of them fit the hypothesized model well.