| Pacific Rim Symposium on Surfaces, Coatings and Interfaces (PacSurf 2016) | |
| Nanomaterials | Tuesday Sessions |
| Session NM-TuP |
| Session: | Nanomaterials Poster Session |
| Presenter: | Hyunhak Jeong, Seoul National University, Republic of Korea |
| Authors: | H. Jeong, Seoul National University, Republic of Korea Y. Jang, Seoul National University, Republic of Korea D. Kim, Seoul National University, Republic of Korea W.-T. Hwang, Seoul National University, Republic of Korea J.-W. Kim, Seoul National University, Republic of Korea T. Lee, Seoul National University, Republic of Korea |
| Correspondent: | Click to Email |
The ultimate aim of molecular electronics is to overcome the limit of the conventional silicon based solid-state electronics by utilizing either single molecules or a bundle of molecules as an active electronic device component. For example, Nijhuis et al. recently reported a robust molecular diode using ferrocene-alkanethiolate self-assembled monolayers (SAMs) and eutectic Ga and In (EGaIn) electrodes.[1] They demonstrated a large rectification ratio of up to ~1000 and reported that the strong asymmetric electrical characteristics could be interpreted by hopping assisted tunneling transport arising from the ferrocene-alkanethiolates and the electrodes.
Similar to these studies, we have also examined the possibility of the electronic device application by fabricating a large number of molecular devices based on ferrocene-alkanethiolate (denoted as FcC) SAMs using a conventional solid-state device fabrication technique both on rigid and flexible substrates.[2] Specifically, we observed a distinctive temperature dependence on the electrical characteristics; that is, the current density decreased as the temperature increased in a certain temperature range when a sufficient voltage was applied with a certain voltage polarity. This behavior was in contrast to the usually expected thermally activated charge transport in the molecular device junction or other device junctions in which, most times, the current density increases as the temperature increases. In that study,[2] we suggested the unusual thermal characteristics are probably due to the redox-induced conformational changes of the FcC in the molecular junctions. While the analysis was quite reasonable and consistent with the experimental results, further evidence was needed to support our suggested explanation. We also performed temperature-dependent transition voltage spectroscopy (TVS) analysis based on a multibarrier tunneling model, which supports the occurrence of the proposed redox-induced conformational changes in the FcC molecular junctions.[3]
References
1. L. Yuan et al., Nano Lett. 15, 5506 (2015).
2. H. Jeong et al., Adv. Funct. Mater. 24, 2472 (2014).
3. H. Jeong et al., J. Phys. Chem. C 120, 3564 (2016).