Li2SrSiO4:Ce3+, Pr3+ Phosphor with Blue,Red, and Near‐Infrared Emissions Used for Plant Growth LED

Ce³⁺/Pr³⁺ codoped Li₂SrSiO₄ (LSS) phosphors with blue, red, and near‐infrared (NIR) tri‐emission have been prepared via a high‐temperature solid‐state reaction method. Under the excitation of 200 to 400 nm near‐ultraviolet (n‐UV), the photoluminescence (PL) spectra of phosphors are composed of visible and NIR two parts. The former exhibits blue and red emission bands centered at around 428 nm from 5d–4f transition of Ce³⁺ and 611 nm from ¹D₂ → ³H₄ transition of Pr³⁺, those overlap with photosynthesis action spectra of plants and absorption spectra of chlorophylls and carotenoids. While the later presents a broad NIR emission band peaking near 1039 nm caused by the ¹G₄ → ³H₄ of Pr³⁺, matching with the absorption of bacteriochlorophyll. Their emission intensity ratios (B: R: NIR) could be tuned by altering the relative ratios of Ce³⁺ and Pr³⁺ concentration in the phosphors to meet the requirements of multifarious plants and bacteria. The efficient energy transfer from Ce³⁺ to Pr³⁺ takes place in the LSS host, which ascribed to an exchange interaction according to PL spectra and decay curves of phosphors. Results suggest that the present LSS: Ce³⁺, Pr³⁺ phosphors have great potential applications in plant growth n‐UV LED.