Tunable luminescence and energy transfer properties of Bi³⁺ and Mn⁴⁺ co-doped Ca₁₄Al₁₀Zn₆O₃₅ phosphors for agricultural applications

Abstract

A novel blue phosphor CAZO:Bi3+ and a color tunable phosphor CAZO:Bi3+,Mn4+ have been synthesized, characterized, and studied. The internal QY of CAZO:Bi3+,Mn4+ is as high as 89.1% due to the energy transfer efficiency from Bi3+ to Mn4+.

Enhanced photoluminescence and energy transfer performance of Y3Al4GaO12:Mn4+,Dy3+ phosphors for plant growth LED lights

“…where h and L S are IQE and the emission spectrum of the sample, E S and E R are the spectra of excitation light with sample and only with BaSO 4 reference, respectively. This IQE is at a low level likes SrLaScO 4 :Mn 4+ (IQE: 12.2%) 53 and Ca 14 Al 10 Zn 6 O 35 :-Mn 4+ (IQE: 19.4%) 54 which have been reported, and the property would be increased further. For clearly describing the energy change in YAGO:Mn 4+ ,Dy 3+ phosphor, the excitation, emission and energy transfer processes of the sample were shown in Fig.…”

None‐rare‐earth activated Ca14Al10Zn6O35:Bi3+,Mn4+ phosphor involving dual luminescent centers for temperature sensing

“…On the other hand, the phenomenon of red shift took place legibly: As shown in Figure C, the peaks of emission bands altered from 405 to 418 nm as the variation of Bi 3+ concentration from 0.0% to 2.5%. Frankly, in most cases, the occurrence of red shift stems mainly from the following three reasons: (a) the improved nephelauxetic effect in the crystal takes place; (b) the enhancement of energy reabsorption occurs; (c) further crystal field splitting because of its change . Considering the facts that no other anions came up during the synthetic process and the overlap between the excitation and emission spectra is negligible, the change of crystal field may mainly account for this phenomenon: by superseding Ca 2+ with Bi 3+ in the crystal lattice due to the difference between these two ionic radii, leading to increase in the crystal field strength around Bi 3+ ion and the splitting of the 6p energy level of Bi 3+ into other sublevels.…”

“…The zincate compound Ca 14 Al 10 Zn 6 O 35 (CAZO) has been corroborated as an excellent host matrix for single‐phased phosphors. Recently, rare‐earth–free ions‐doped CAZO phosphors which were composed of nontoxic elements such as Ti 4+ , Bi 3+ , Mn 4+ have been reported . However, for self‐referencing temperature sensing, high sensitivity and signal discriminability are needed, thus optical materials with dual activators are more preferred than the singly doped materials by considering that the host itself does not show any emission bands.…”

“…Recently, rare-earth-free ions-doped CAZO phosphors which were composed of nontoxic elements such as Ti 4+ , Bi 3+ , Mn 4+ have been reported. 29,32,33 However, for self-referencing temperature sensing, high sensitivity and signal discriminability are needed, thus optical materials with dual activators are more preferred than the singly doped materials by considering that the host itself does not show any emission bands. What's more, in CAZO: Ti 4+ , Mn 4+ -co-doped phosphor, 29 when the Concentration of Ti 4+ reached as high as 0.15 mol, an impure phase of CaO was clearly observed.…”

Novel far-red-emitting SrGdAlO4:Mn4+ phosphors with excellent responsiveness to phytochrome PFR for plant growth lighting

“…In agricultural production, the lighting conditions are directly related to the success of agricultural production. 1,2 With the development of modern agriculture, the demand and energy consumption of plant lighting are expanding. 3 Using lightemitting diodes (LEDs) as articial light sources has become an inevitable choice for agricultural development.…”