Fluorescence quenching in ceria nanoparticles: dissolved oxygen molecular probe with relatively temperature insensitive Stern–Volmer constant up to 50°C

Shehata, N., Meehan, K. and Leber, D. E. (2012) Fluorescence quenching in ceria nanoparticles: dissolved oxygen molecular probe with relatively temperature insensitive Stern–Volmer constant up to 50°C. Journal of Nanophotonics, 6(1), 063529. (doi: 10.1117/1.JNP.6.063529)

Abstract

Ceria nanoparticles (∼7  nm in diameter) were used as a molecular probe for dissolved oxygen sensing based on fluorescence quenching. Strong inverse correlation was found between the amplitude of the fluorescence emission at 520 nm (from excitation shift at 430 nm) and the dissolved oxygen concentration (between 5  and 13  mg/L). The phenomenon employed depends on the concentration, diffusion, and reactivity of the oxygen vacancies in ceria. These vacancies are associated with the conversion of cerium ions from the Ce+4 to Ce+3 states. The Stern–Volmer constant, which is an indication of the sensitivity of gas sensing, was found to be 184.6  M−1 at room temperature. This constant shows good stability between 25°C to 50°C when compared to that of other currently used fluorophores in optical oxygen sensors.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Meehan, Professor Kathleen
• Authors: Shehata, N., Meehan, K., and Leber, D. E.
• College/School: College of Science and Engineering > School of Engineering
• Journal Name: Journal of Nanophotonics
• Publisher: SPIE
• ISSN: 1934-2608