The Influence of Interfacial Effects on the Photophysics of Rhodamine 6G Thin Films on a Poly(vinylidene fluoride) Surface

Abstract

The spectral response of ultrathin films of rhodamine 6G (Rh6G) cast onto polyvinylidenefluoride (PVDF) coated glass slides is studied to investigate a perceived fluorescence emission enhancement. Varying the thickness of the Rh6G layer (submonolayer to multiple layers) on the PVDF layer revealed the existence of multiple Rh6G species on the surface, similar to previous reports on glass. Excitation spectra show that J-type excitons are not responsible for an emission enhancement. Trends in the fluorescence emission intensity show that the surface roughness of the PVDF layer prevents the Rh6G molecules from organizing the way they would on a smooth glass surface. The PVDF surface roughness preserves the emissive monomers and excited-state excimers of Rh6G while reducing the self-quenching of aggregates. Coupled with this is an internal reflection effect that causes light to be trapped between the Rh6G/PVDF and PVDF/glass interfaces. This effect leads to multiple absorption events, and thus more efficient use of the incident light.

Influence of an Interfacial Effect on the Laser Performance of a Rhodamine 6G/Cellulose Acetate Waveguide on a Vinylidene Fluoride Copolymer Layer

“…This is consistent with the result reported recently by Mullen and Euler . In a previous report, the roughness of the surface was shown to preserve the emissive R6G dyes, which enhanced the fluorescence intensity.…”

“…This is consistent with the previously reported result. 14 Futhermore, P(VDF-TrFE) has large dielectric moments because of the noncentrosymmetrically aligned polar β-crystals (ferroelectric). The interaction between polar β-crystals and R6G dye might be responsible for the fluorescence enhancement.…”

“…Motivation of the present article is based on the fact that the surface roughness of poly­(vinylidene fluoride) (PVDF) preserves emissive rhodamine 6G (R6G) dyes coated onto a PVDF layer . The surface properties of P­(VDF-TrFE) can be suitably tailored for applications. , We hypothesized that the preservation of the emissive R6G dyes due to the interaction between large dipole moments due to non-centrosymmetric alignment of vinylidene fluoride (VDF) and trifluoroethylene (TrFE) moieties in P­(VDF-TrFE) and R6G dyes will enhance laser emission, especially via improvement of the SE.…”

Investigation of Self-Emulsifying Drug-Delivery System Interaction with a Biomimetic Membrane under Conditions Relevant to the Small Intestine

“…Planar substrates with porous PVDF thin films were prepared based on the protocol developed by Mullen & Euler. 40 Briefly, PVDF (4% wt/vol) was dissolved in a 9:1 solution of acetone and N , N -dimethylformamide by sonicating for 3 h at 40 °C. The PVDF solution was then applied to a dried and nitrogen purged silica substrate (QCM-D crystal or glass) by spin coating.…”

“…Planar substrates with porous PVDF thin films were prepared based on the protocol developed by Mullen & Euler . Briefly, PVDF (4% wt/vol) was dissolved in a 9:1 solution of acetone and N , N -dimethylformamide by sonicating for 3 h at 40 °C.…”