Tunable trap depth in Zn(Ga1−xAlx)2O4:Cr,Bi red persistent phosphors: considerations of high-temperature persistent luminescence and photostimulated persistent luminescence

Abstract

Al-containing ZnGa 2 O 4 :Cr,Bi phosphors could be a promising technique for new in vivo imaging systems.patterns of Zn(Ga 1Àx Al x ) 2 O 4 :Cr,Bi (x ¼ 0, 0.02, and 0.04) phosphors (Fig. S1). Measurement system of NIR photostimulated persistent luminescence (Fig. S2). X-ray powder diffraction patterns of Zn(Ga 1Àx Al x ) 2 O 4 :Cr,Bi (x ¼ 0, 0.02, and 0.04) phosphors (Fig. S3). TL glow curves of Zn(Ga 1Àx Al x ) 2 O 4 :Cr,Bi (x ¼ 0, 0.02, 0.04, and 0.33) phosphors (Fig. S4). Initial rise approach to estimate the depths of electron traps by plotting of ln(I) versus 1000/T (Fig. S5). TL glow curves of Zn(Ga 0.96 Al 0.04 ) 2 O 4 :Cr,Bi phosphors combined with and without NIR photostimulation (Fig. S6).

In Vivo Repeatedly Charging Near‐Infrared‐Emitting Mesoporous SiO2/ZnGa2O4:Cr3+ Persistent Luminescence Nanocomposites

“…[7–10] To address this problem, a NIR-light-stimulated PL mechanism was proposed in LiGa 5 O 8 :Cr 3+ , to release energy trapped in deeper energy levels of the phosphor, but in this case, the energy must be precharged by UV-light and the photostimulated emission continues to weaken after each cycle of photostimulation and will finally become extinguished. [3,11] Very recently, the PL phosphor, ZnGa 2 O 4 :Cr 3+ (ZGC), was found to be activatable by using tissue-penetrable red light, which means that energy can be recharged and NIR PL imaging is no longer limited by the luminescence-decay life-time of the phosphor. [12] Thus ZGC is arguably the optimal rechargeable NIR persistent emitting phosphor reported to date.…”

Tailoring of the trap distribution and crystal field in Cr3+-doped non-gallate phosphors with near-infrared long-persistence phosphorescence

“…In addition to ZnGa 2 O 4 : Cr 3+ , La 3 Ga 5 3+ , were investigated because of the excellent ability of Cr 3+ ions to substitute for Ga 3+ ions in distorted octahedral coordination. [9][10][11][12][13][14][15][16][17][18][19][20] The predominance of Cr 3+ -activated gallates might suggest that only gallates can be used as the hosts in Cr 3+ -doped NIR LPPs. Such a dependence would result in the trapping and de-trapping processes being closely associated with the crystalline structure or energy band structure, of gallates because a variety of defects in gallate materials, including antisite defects and Ga vacancies, have been proposed as an electron (or hole) reservoir to improve the afterglow properties.…”

“…6 Such biomarkers are expected to enable advanced optical imaging with high-resolution and minimal excitation disturbance to experimentally assess structural and functional processes in cells, tissues and other complexes in in vivo systems. 7 Over the past few years, substantial strides have been made in the research and development of LPPs for NIR wavelengths, [8][9][10][11][12][13][14][15][16][17][18][19][20] with the main focus of the research being Mn 2+ , Mn 4+ and Cr 3+ -activated NIR LPPs. In 2007, Chermont et al proposed a novel bio-imaging method using red-to-NIR persistent nanoparticles, Ca 0.2 Zn 0.9 Mg 0.9 Si 2 O 6 : Eu 2+ , Dy 3+ , Mn 2+ , and opened a new application area for NIR LPPs.…”

Correlations between Glass Structure and Emission Properties of Sn-Doped Zinc Phosphate Glasses Prepared with Different Cooling Rates

“…(16)(17)(18) Thermally stimulated luminescence (TSL) and optically stimulated luminescence (OSL) properties were thoroughly investigated in order to discuss the energy levels and the density of traps. (16)(17)(18) In a previous study, it was demonstrated that the addition of carbon to a glass batch is effective in obtaining a reducing atmosphere during the melting process; therefore, the reduced state of emission centers is increased. (19) Moreover, it has been reported that the number of defect sites are increased in glasses and crystal systems.…”