Highly luminescent hybrid materials based on smectites with polyethylene glycol modified with rhodamine fluorophore

0468444 - ÚACH 2018 RIV NL eng J - Journal Article
Sas, S. - Danko, M. - Bizovská, V. - Lang, Kamil - Bujdák, J.
Highly luminescent hybrid materials based on smectites with polyethylene glycol modified with rhodamine fluorophore.
Applied Clay Science. Roč. 138, MAR (2017), s. 25-33. ISSN 0169-1317. E-ISSN 1872-9053
Institutional support: RVO:61388980
Keywords : Luminescent polymers * Rhodamine B * Molecular aggregation * Fluorescence * Optical materials
OECD category: Inorganic and nuclear chemistry
Impact factor: 3.641, year: 2017

Highly luminescent anisotropic materials are promising for light harvesting systems, sensors, solid lasers and optical devices. To achieve this, polyethylene glycol (PEG) was derivatized with a reactive rhodamine B (RhB) fluorophore to produce a luminescent, water-soluble and positively-charged polymer (RhPEG) that can be intercalated between layers of smectites. An optimal degree of polymer derivatization was applied to avoid fluorescence quenching. The optical properties of RhPEG were similar to those of the RhB precursor. Colloids were prepared using RhPEG and the montmorillonite Kunipia (Mt) and the synthetic saponite Sumecton (Sap), with polymer/smectite mass ratios of 0.05–0.25, and were cast into thin solid films by a vacuum filtration deposition technique. The luminescent hybrid films exhibited a similar structure to those obtained by the intercalation of non-modified PEG. Optical properties depended considerably on the smectite type. The hybrid films made of Sap, the smectite with low charge density, negligibly induced the molecular aggregation of RhPEG and had high fluorescence quantum yields, similar to dilute solutions of RhB or RhPEG. On the other hand, the results of spectroscopic methods indicated molecular aggregation of RhPEG when intercalated between Mt layers leading to considerable fluorescence quenching, making this material unsuitable for the fabrication of photoactive optical films.

Permanent Link: http://hdl.handle.net/11104/0269459