Ruthenium aminophenanthroline metallopolymer films electropolymerized from an ionic liquid: deposition and electrochemical and photonic properties.
The oxidative electropolymerization of [Ru(aphen)3](PF6)2 from an ionic liquid, 1-butyl-2,3-dimethylimidazolium bis[(trifluoromethyl)sulfonyl]imide (BDMITFSI), is reported; aphen is 5-amino-1,10-phenanthroline. The deposition rate in the ionic liquid is more than an order of magnitude faster than in conventional solvents such as anhydrous acetonitrile and aqueous sulfuric acid. The UV-vis absorbance, Raman, and emission spectra of the films grown in ionic liquid, acetonitrile, and sulfuric acid suggest that the polymer formed does not depend on the solvent. However, scanning electron microscopy shows that the film morphologies differ significantly; e.g., films deposited from BDMITFSI have high surface roughness, while films produced in acetonitrile and sulfuric acid are relatively smooth. The rate of homogeneous charge transport through films grown in ionic liquids is (6.4 +/- 1.2) x 10(-9) cm (2) s (-1), which is approximately 2 orders of magnitude faster than that found for films deposited from acetonitrile. Thin electropolymerized films generate electrochemiluminescence (ECL) in the presence of tripropylamine as a coreactant. Films produced from sulfuric acid are very thin compared to the ones produced in BDMITFSI; however, they produce an ECL signal of similar intensity. The ECL responses of films produced in anhydrous acetonitrile are significantly less intense. The ECL intensity within the films is approximately 5-fold higher than when they are dissolved and measured in solution.
Venkatanarayanan
Anita
A
The Biomedical Diagnostics Institute, National Centre for Sensor Research, School of Chemical Sciences, Dublin University, Dublin, Ireland.
Spehar-Délèze
Anna-Maria
AM
Dennany
Lynn
L
Pellegrin
Yann
Y
Keyes
Tia E
TE
Forster
Robert J
RJ
D004563:Electrochemistry; D052578:Ionic Liquids / Q000737:chemistry*; D049449:Luminescence; D008855:Microscopy, Electron, Scanning; D009942:Organometallic Compounds / Q000737:chemistry*; D010618:Phenanthrolines / Q000737:chemistry*; D010777:Photochemistry; D011108:Polymers / Q000737:chemistry*; D013059:Spectrum Analysis, Raman; D013464:Sulfuric Acids / Q000737:chemistry
D052578:Ionic Liquids; D009942:Organometallic Compounds; D010618:Phenanthrolines; D011108:Polymers; D013464:Sulfuric Acids; C532462:ruthenium aminophenanthroline; C033158:sulfuric acid