Structural and Optical Characterisation of an Erbium/Ytterbium Doped Hybrid Material Developed via a Nonhydrolytic Sol-Gel Route

Abstract

This paper proposes the development and structural characterisation of an Er 3 + / Yb 3 + doped hybrid organic-inorganic material synthesised by a nonhydrolytic sol-gel process. By using a pumping laser diode at 980 nm, a typical Er 3 + luminescence has been recorded in the near infrared region (1.53–1.55 μ m). However, the detected fluorescence was particularly weak compared to that generally observed in pure mineral materials, suggesting the occurrence of strong quenching due to multiphonon relaxation processes. To understand this behaviour, structural characterisation of both of the matrix and the local environment of Er 3 + ions were conducted employing infrared spectroscopy, nuclear magnetic resonance, electron paramagnetic resonance, and neutron scattering. These studies showed that the major phenomenon competing with the Er 3 + fluorescence is intimately associated to the strong vibrational modes of the organic species that involve multiphonon relaxation processes, resulting in energy dissipation within the host matrix.