11:30 AM - 11:45 AM
▼ [18a-C310-8] Room-Temperature Detection of Single-Electron Transfer in N719 Redox State by Frequency-mode AFM
Keywords:atomic force microscope, Ru-dye complex, single-electron tunneling
The sensitizing dye molecule, N719, is a potential candidate in molecular electronics, where the charge state can be stably changed due to highly localized frontier molecular orbitals. This characteristic provides an exploration of electron transfer in molecular states transitions for redox chemistry.In this work, probing the electronic propertiesof N719 on quantum confined surface investigates electron transfer between a tunnel barrier and capacitively coupled electrodes. Measurement of electron injection is setup to characterize the molecular state of N719 under atomic force microscopy (AFM) platform in room-temperature environment.
To detect the electron transfer process, the cantilever tip monitors dynamic motion under frequency modulated mode AFM (FM-AFM) combined with non-contact scanning morphology above the sample surface. The scanning topography displays the distribution of N719 on 6-aminohexanethiolself-assembled monolayer (SAM) grown on a gold substrate, helping inAFMtip located at the nanometer scale. FM-AFM probes the electronic excitations by tip oscillating above N719 when applied dc-bias voltage across the capacitive interfaces, detecting the tunneling electrons through SAM layer and injection of the electrons in and out of N719. These electronic excitations are recorded by the spectra of oscillating frequency shift versus bias, showing the electron transfer occurred at a specific energy. The intermediary region of oscillating mode shifting indicates the transfer of redox electrons when applied bias surpasses the ionization energy of N719. This technique refers to as single-electron electric force microscope (e-EFM) used to analyze the electronic structure of single molecule.
To detect the electron transfer process, the cantilever tip monitors dynamic motion under frequency modulated mode AFM (FM-AFM) combined with non-contact scanning morphology above the sample surface. The scanning topography displays the distribution of N719 on 6-aminohexanethiolself-assembled monolayer (SAM) grown on a gold substrate, helping inAFMtip located at the nanometer scale. FM-AFM probes the electronic excitations by tip oscillating above N719 when applied dc-bias voltage across the capacitive interfaces, detecting the tunneling electrons through SAM layer and injection of the electrons in and out of N719. These electronic excitations are recorded by the spectra of oscillating frequency shift versus bias, showing the electron transfer occurred at a specific energy. The intermediary region of oscillating mode shifting indicates the transfer of redox electrons when applied bias surpasses the ionization energy of N719. This technique refers to as single-electron electric force microscope (e-EFM) used to analyze the electronic structure of single molecule.