Room-temperature synthesis of near-ultraviolet light-excited Tb3+-doped NaBiF4 green-emitting nanoparticles for solid-state lighting

Abstract

We reported a facile reaction technique to prepare Tb³⁺-doped NaBiF₄ green-emitting nanoparticles at room temperature. Under 378 nm excitation, the prepared samples exhibited the featured emissions of Tb³⁺ ions and the green emission located at 543 nm corresponding to the ⁵D₀ → ⁷F₄ transition was observed in the photoluminescence (PL) emission spectra. The PL emission intensity relied on the dopant concentration and its optimum value was determined to be 50 mol%. The involved concentration quenching mechanism was dominated by the electric dipole–dipole interaction and the critical distance was evaluated to be around 10.4 Å. Meanwhile, the color coordinate and color purity of the obtained emission were revealed to be (0.328, 0.580) and 62.4%, respectively. The thermal quenching performance of the synthesized nanoparticles was analyzed using the temperature-dependent PL emission spectra and the activation energy was calculated to be 0.39 eV. By integrating a near-ultraviolet chip with the prepared nanoparticles, a dazzling green light-emitting diode was fabricated to explore the feasibility of the Tb³⁺-doped NaBiF₄ nanoparticles for solid-state lighting applications.