Synthesis and photoluminescence properties of novel red-emitting phosphor SrAl3BO7:Mn4+ with enhanced emission by Mg2+/Zn2+/Ca2+ incorporation for plant growth LED lighting

Abstract Indoor cultivation has attracted more and more concerns in the last few years. Searching for ideal red-emitting phosphors for this application has been a great challenge. In this paper, a novel red-emitting phosphor SrAl3BO7:Mn4+ (SABO:Mn4+) had been synthesized through a modified hydrothermal reaction method for the first time. Three kinds of effect parameters, including hydrothermal reacting time, sintering temperature and Mn4+ doping concentration, were comprehensively considered to optimize the phase purity and luminescent properties of the SABO:Mn4+ phosphor. Besides, the luminescent properties of SABO:Mn4+ was systematically investigated through UV–vis absorption spectra, PLE and PL spectra, CIE chromaticity coordinate and decay times. The excitation band of this phosphor locates in the wavelength range of 250–550 nm, resulting from Mn4+ → O2− charge transfer and electron transitions from 4A2–4T1, 2T2 and 4T2 energy levels. Meanwhile, a sharp emission band is detected from 600 to 700 nm with two emission peaks located at 648 and 662 nm, which is assigned to 2E → 4A2 characteristic transition of Mn4+. In addition, Mg2+/Zn2+/Ca2+ are co-doped as charge compensators to improve the luminescent properties of SABO:0.03Mn4+. The impacts of doping concentration of Mg2+/Zn2+/Ca2+ on the photoluminescent intensity, QE and thermal stability of SABO:0.03Mn4+ phosphor is investigated carefully. The corresponding mechanism is discussed via decay times, EPR spectra and configurational coordinated diagram. More importantly, the EL spectrum of as-fabricated pc-LED device matches well with the absorption of plant pigments, demonstrating this novel phosphor can regard as a promising red-emitting luminescent material to meet the light requirement in plant growth LED lighting.