Tailoring of Spectral Behaviors in Ce3+-Activated Ba2Gd8(SiO4)6O2 Cyan-Emitting Phosphors via Site Substitution Engineering for Plant Growth and Full-Spectrum White Light-Emitting Diodes.

Abstract

Highly efficient Ce³⁺-activated Ba₂Gd₈(SiO₄)₆O₂ (BGSO) cyan-emitting phosphors were designed to simultaneously fulfill the applications of plant growth and a white-light-emitting diode (white-LED). Here, the spectral behaviors of the studied samples are manipulated by arranging Ce³⁺ to occupy various crystallographic sites (i.e., Ba²⁺ and Gd³⁺) in BGSO host lattices. Upon ultraviolet light excitation, all the samples emit an intense asymmetric broadband emission from Ce³⁺ and its fluorescence intensity is strongly impacted by the dopant concentration and occupied position. In addition, the resultant phosphors do not only possess satisfied thermal stability but also present high internal and extra quantum efficiencies of 78.6 and 61.8%, respectively, which can be regulated by selecting the substituted sites. Two cyan-emitting LEDs are fabricated by integrating the synthesized phosphors, and their emission bands align well with the absorption peaks of plant pigments, enabling their uses in plant growth. Furthermore, the controlled plant growth environments also clarify that the packaged cyan-emitting LED can effectively promote plant growth. Additionally, via adopting the resulting phosphors as cyan-emitting converters, full-spectrum white-LED with good electroluminescence behaviors is developed. These findings manifest that the Ce³⁺-activated BGSO phosphors with tunable spectral properties are promising cyan-emitting components for both artificial plant growth LED and full-spectrum white-LED.