Garnet Structure-Activated Warm White Light Phosphors Ca3Al2Ge3O12: Dy3+, Eu3+ with Ultrahigh Thermal Stability and Tunable Luminescence

Lingbo Zhou; Rujia Chen; Xiliang Jiang; Tianqing Zhang; Xueming Shi; Zhuang Leng; Yimin Yang; Zhipeng Zhang; Chunyu Zuo; Chun Li; Weiling Yang; Hai Lin; Lina Liu; Shasha Li; Fanming Zeng; Zhongmin Su

doi:10.1021/acs.inorgchem.3c03739

Garnet Structure-Activated Warm White Light Phosphors Ca₃Al₂Ge₃O₁₂: Dy³⁺, Eu³⁺ with Ultrahigh Thermal Stability and Tunable Luminescence

Inorg Chem. 2024 Jan 15;63(2):1274-1287. doi: 10.1021/acs.inorgchem.3c03739. Epub 2024 Jan 2.

Authors

Lingbo Zhou^{1

2}, Rujia Chen^{1

2}, Xiliang Jiang^{1

2}, Tianqing Zhang^{1

2}, Xueming Shi^{1

2}, Zhuang Leng^{1

2}, Yimin Yang^{1

2}, Zhipeng Zhang^{1

2}, Chunyu Zuo^{1

2}, Chun Li^{1

2}, Weiling Yang^{1

2}, Hai Lin^{1

2}, Lina Liu^{1

2}, Shasha Li^{1

2}, Fanming Zeng^{1

2}, Zhongmin Su³

Affiliations

¹ School of Materials Science and Engineering, Changchun University of Science and Technology, Changchun 130022, China.
² Ministry of Education, Engineering Research Center of Optoelectronic Functional Materials, Changchun 130022, China.
³ Jilin University, Changchun 130012, P. R. China.

PMID: 38165643
DOI: 10.1021/acs.inorgchem.3c03739

Abstract

A series of Ca₃Al₂Ge₃O₁₂: xDy³⁺, yEu³⁺ phosphors were successfully prepared by the high-temperature solid-phase method. The phase and morphology of the phosphors were studied by means of Rietveld refinement and scanning electron microscopy. The results show that the phase is pure, and the crystal structure is the Ia3̅d space group. In the Ca₃Al₂Ge₃O₁₂: xDy³⁺ phosphors, using 380 nm excitation, phosphors showed blue (⁴F_9/2 → ⁶H_15/2) and yellow (⁴F_9/2 → ⁶H_13/2) emission peaks at 481 and 581 nm, respectively. In Ca₃Al₂Ge₃O₁₂: xDy³⁺, yEu³⁺ phosphors, the energy transfer was inferred by the spectrum overlap of Dy³⁺ and Eu³⁺, and the lifetime attenuation was analyzed from the perspective of dynamics; finally, the band gap structure of the phosphors was analyzed by combining diffuse reflection spectra with the first principle, and the energy transfer mechanism and luminescence mechanism were elaborated by combining theory and practice. The transition from blue white light to red light can be achieved by tuning the range of y in Ca₃Al₂Ge₃O₁₂: 0.015Dy³⁺, yEu³⁺. Wherein, when y = 0.07, phosphors, the chromaticity coordinate of warm white CIE is (0.3932, 0.3203), the color temperature is 3093 K, and the warm white light is synthesized. The thermal stability of the synthesized warm white phosphors is 90.1% (423 K), the thermal sensing factors are S_amax = 5.51 × 10^-4 K^-1 (303 K) and S_rmax = 0.0359% K^-1 (303 K), and the actual quantum efficiency is IQE = 52.48%. These results prove that Ca₃Al₂Ge₃O₁₂: Dy³⁺, Eu³⁺ have good application prospects as single-component warm w-LED devices.