Electron Transport Behavior Analysis of Bis(terpyridine)Metal Complex Wires on Electrodes

摘要

Bis(terpyridine)iron(II) complex (Fe(tpy)_2) wires terminated with redox active molecules were sequentially constructed on gold and hydrogen-terminated silicon electrodes. Potential-step chronoamperometry (PSCA) and electrochemical impedance spectroscopy (EIS) were performed to study the electron transfer of ferrocene-Fe(tpy)_2 arrays on gold surfaces. The obtained Tafel plots and impedance spectra revealed greater first-order electron transfer rate constant than a ferrocene-terminated alkanethiol self-assembled monolayer and parameters contributing the smooth electron transport. On silicon electrodes, ferrocene-terminated Fe(tpy)_2 wires showed slow electron transport between the ferrocene and the electrode while triarylamine-terminated Fe(tpy)_2 wires displayed rapid electron transport. The difference of electron transport behaviors was discussed based on the band structure of silicon electrode and the HOMO level of terminal redox units.