Unexpected current–voltage characteristics of mechanically modulated atomic contacts with the presence of molecular junctions in an electrochemically assisted–MCBJ
molecular junction, electrochemical deposition, mechanically controllablebreak junction (MCBJ), ruthenium complex, ferrocenyl molecular wire
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(II) 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.
Tsinghua University Press
Yang Yang,Junyang Liu,Shi Feng,Huimin Wen,Jinghua Tian,Jueting Zheng,Bernd Schöllhorn,Christian Amatore,Zhongning Chen,Zhongqun Tian, Unexpected current–voltage characteristics of mechanically modulated atomic contacts with the presence of molecular junctions in an electrochemically assisted–MCBJ. NanoRes.2016, 9(2): 560–570