Adsorption of Expanded Pyridinium Molecules at the Electrified Interface and Its Effect on the Electron-Transfer Process

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61388955%3A_____%2F18%3A00490605" target="_blank" >RIV/61388955:_____/18:00490605 - isvavai.cz</a>

Výsledek na webu

<a href="http://dx.doi.org/10.1021/acs.langmuir.8b00671" target="_blank" >http://dx.doi.org/10.1021/acs.langmuir.8b00671</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1021/acs.langmuir.8b00671" target="_blank" >10.1021/acs.langmuir.8b00671</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Adsorption of Expanded Pyridinium Molecules at the Electrified Interface and Its Effect on the Electron-Transfer Process

Popis výsledku v původním jazyce

Adsorption properties of a series of redox-active expanded pyridinium molecules were studied at an electrified interface by cyclic and alternating current voltammetry methods. It was shown that the adsorbed state can sufficiently block N-pyramidalization of the pyridinium redox center of 2′,6′-diphenyl-[4,1′:4′,4′′-terpyridin]-1′-ium tetrafluoroborate (2), leading to a change of the mechanism from a single two-electron-transfer process to stepwise transfer of two electrons. Chemically locked molecules 1, 9-(pyridin-4-yl)benzo[c]benzo[1,2]quinolizino[3,4,5,6-ija][1,6]naphthyridin-15-ium tetrafluoroborate (ring fusion), and 3, 3,5-dimethyl-2′,6′-diphenyl-[4,1′:4′,4′′-terpyridin]-1′-ium tetrafluoroborate (steric hindrance) do not enable N-pyramidalization of the redox center upon electron transfer (ET) and serve as references. It was shown that 1 follows Langmuir-type adsorption around a potential of zero charge and that 1-3 form a close-packed film with some repulsive interactions between individual molecules at potentials where ET takes place. It has been suggested that all three molecules lie flat on the electrode surface, with the lowest free energy of adsorption found for 2. Maximum surface concentration Γ∗ equal to (1.4 ± 0.1) × 10-10mol·cm-2was found for 1, (1.5 ± 0.1) × 10-10mol·cm-2for 2, and (1.6 ± 0.1) × 10-10mol·cm-2for 3. These findings will help to clarify the role of molecular contacts with conducting substrate in the single-molecule electron-transport measurements of 1-3 during the metal-molecule-metal junction formation process.

Název v anglickém jazyce

Adsorption of Expanded Pyridinium Molecules at the Electrified Interface and Its Effect on the Electron-Transfer Process

Popis výsledku anglicky

Adsorption properties of a series of redox-active expanded pyridinium molecules were studied at an electrified interface by cyclic and alternating current voltammetry methods. It was shown that the adsorbed state can sufficiently block N-pyramidalization of the pyridinium redox center of 2′,6′-diphenyl-[4,1′:4′,4′′-terpyridin]-1′-ium tetrafluoroborate (2), leading to a change of the mechanism from a single two-electron-transfer process to stepwise transfer of two electrons. Chemically locked molecules 1, 9-(pyridin-4-yl)benzo[c]benzo[1,2]quinolizino[3,4,5,6-ija][1,6]naphthyridin-15-ium tetrafluoroborate (ring fusion), and 3, 3,5-dimethyl-2′,6′-diphenyl-[4,1′:4′,4′′-terpyridin]-1′-ium tetrafluoroborate (steric hindrance) do not enable N-pyramidalization of the redox center upon electron transfer (ET) and serve as references. It was shown that 1 follows Langmuir-type adsorption around a potential of zero charge and that 1-3 form a close-packed film with some repulsive interactions between individual molecules at potentials where ET takes place. It has been suggested that all three molecules lie flat on the electrode surface, with the lowest free energy of adsorption found for 2. Maximum surface concentration Γ∗ equal to (1.4 ± 0.1) × 10-10mol·cm-2was found for 1, (1.5 ± 0.1) × 10-10mol·cm-2for 2, and (1.6 ± 0.1) × 10-10mol·cm-2for 3. These findings will help to clarify the role of molecular contacts with conducting substrate in the single-molecule electron-transport measurements of 1-3 during the metal-molecule-metal junction formation process.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10405 - Electrochemistry (dry cells, batteries, fuel cells, corrosion metals, electrolysis)

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2018

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Langmuir

ISSN

0743-7463

e-ISSN

—

Svazek periodika

34

Číslo periodika v rámci svazku

22

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

8

Strana od-do

6405-6412

Kód UT WoS článku

000434893600010

EID výsledku v databázi Scopus

2-s2.0-85047071190