Photon-conversion and sensitization evaluation of Eu³⁺ in a borate glass system

Photon conversion is exhibited in a borate (LKZBSB) glass system containing Eu³⁺, and the enhanced characteristic emissions of Eu³⁺ with the codoping of Ce³⁺ have been verified. A large Judd-Ofelt intensity parameter ω₂ of Eu³⁺ indicates a high asymmetrical and strong covalent environment around rare-earth (RE) ions in LKZBSB glasses and spontaneous emission probability and a maximum emission cross section of the dominant ⁵D₀ → ⁷F₂ transition were derived to be 370 s^-1 and 1.28 × 10^-21 cm², respectively, revealing the potential UV → visible photon-conversion capacity of Eu³⁺. Absolutely quantitative evaluation illustrates that Eu³⁺ is a favorable photonconversion center to achieve high photon-conversion efficiency. The addition of Ce³⁺ is beneficial to realizing effective red emission of Eu³⁺, which possesses commercial value by decreasing the dopant of expensive europium compounds. As an expectation, this photon-conversion LKZBSB glass system can promote the development of a photon downconversion layer for solar cells, which are particularly used in outer space with intense UV radiation.