Far-red emitting Li2TiO3: Cr3+ phosphor: Synthesis, luminescence properties and potential applications

Abstract

The Cr[Formula: see text]-activated phosphor can emit far-red light under the excitation of an external light source, mainly due to the transition of the outermost electrons of Cr[Formula: see text] from the 2E level to the 4A2 level in a strong crystal field environment. A novel far-red Li2TiO3: Cr[Formula: see text] phosphor was prepared by the solid-state method. Under the excitation of 356[Formula: see text]nm, the Li2TiO3: Cr[Formula: see text] phosphors emit intense far-red light in 600–850[Formula: see text]nm with a central wavelength of 732[Formula: see text]nm. The emission band of all samples was matched with the absorption bands of phytochrome P[Formula: see text]. The experimental data and theoretical calculation confirmed that Cr[Formula: see text] is surrounded by a strong crystal field environment. The effect of Cr[Formula: see text] doping concentration on the luminescence intensity was analyzed. These research works demonstrate that far-red Li2TiO3: Cr[Formula: see text] phosphors have potential applications in plant growth lights.