The effect of electron cloud expansion on the red luminescence of Sr4Al14O25:Mn4+ revealed by calculation of the Racah parameters

Chen, Lei; Deng, Xiaorong; Zhao, Erlong; Chen, Xiuling; Xue, Shaochan; Zhang, Wenqiang; Chen, Shifu; Zhao, Zhi; Zhang, Wenhua; Chan, Ting‐Shan

doi:10.1016/j.jallcom.2014.06.029

Cited by 41 publications

(10 citation statements)

References 23 publications

(59 reference statements)

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“…The excitation spectra depict a broadband ranging from 225–430 nm with a maximum excitation band centered at λ exc = 370 nm and a shoulder at λ sh = 310 nm. The maximum excitation at 370 nm is consistent with the transitions between the ground state 4f 7 ( 8 S 7/2 ) and the excited state 4f 6 5d 1 of the Eu 2+ ions and the shoulder at 310 nm is associated with the charge‐ transfer band (CTB) transition of Eu 2+ . The emission spectra show the typical greenish‐blue emission centered at 495 nm that corresponds to the allowed 5d–4f transition of Eu 2+ ions .…”

Section: Resultssupporting

confidence: 54%

Enhancing the Photocatalytic Activity of Sr₄Al₁₄O₂₅: Eu²⁺, Dy³⁺ Persistent Phosphors by Codoping with Bi³⁺ Ions

García

Oliva

Martín‐Romero

et al. 2016

Photochem & Photobiology

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The photocatalytic activity of Bismuth-codoped Sr Al O : Eu , Dy persistent phosphors is studied by monitoring the degradation of the blue methylene dye UV light irradiation. Powder phosphors are obtained by a combustion synthesis method and a postannealing process in reductive atmosphere. The XRD patterns show a single orthorhombic phase Sr Al O : Eu , Dy , Bi phosphors even at high Bismuth dopant concentrations of 12 mol%, suggesting that Bi ions are well incorporated into the host lattice. SEM micrographs show irregular micrograins with sizes in the range of 0.5-20 μm. The samples present an intense greenish-blue fluorescence and persistent emissions at 495 nm, attributed to the 5d-4f allowed transitions of Eu . The fluorescence decreases as Bi concentration increases; that suggest bismuth-induced traps formation that in turn quench the luminescence. The photocatalytic evaluation of the powders was studied under both 365 nm UV and solar irradiations. Sample with 12 mol% of Bi presented the best MB degradation activity; 310 min of solar irradiation allow 100% MB degradation, whereas only 62.49% MB degradation is achieved under UV irradiation. Our results suggest that codoping the persistent phosphors with Bi can be an alternative to enhance their photocatalytic activity.

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Section: Resultssupporting

confidence: 54%

Enhancing the Photocatalytic Activity of Sr₄Al₁₄O₂₅: Eu²⁺, Dy³⁺ Persistent Phosphors by Codoping with Bi³⁺ Ions

García

Oliva

Martín‐Romero

et al. 2016

Photochem & Photobiology

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“…The values of Δ/ B for the four- and six-coordinated Fe 3+ were determined to be 16.1 and 14.0, respectively. The values of Δ for the four and six-coordinated Fe 3+ in MSO host were correspondingly calculated to be 10358 cm –1 ( B = 643 cm –1 ) and 8961 cm –1 ( B = 640 cm –1 ), respectively . Consequently, as illustrated by the energy-level diagram in Figure b, the emission wavelength of Fe 3+ originating from Fe–O 4 (corresponding to PL peak 2) is larger than that from Fe–O 6 (corresponding to PL peak 1).…”

Section: Resultsmentioning

confidence: 99%

Near-Infrared Long Afterglow in Fe³⁺-Activated Mg₂SnO₄ for Self-Sustainable Night Vision

Jin

Yuan³

et al. 2023

ACS Appl. Mater. Interfaces

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The advent of near-infrared (NIR) afterglow in Cr 3+ -doped materials has stimulated considerable interest in technological applications owing to the sustainable emission of light with good penetrability. However, the development of Cr 3+ -free NIR afterglow phosphors with high efficiency, low cost, and precise spectral tunability is still an open question. Herein, we report a novel Fe 3+ -activated NIR long afterglow phosphor composed of Mg 2 SnO 4 (MSO), in which Fe 3+ ions occupy the tetrahedral [Mg−O 4 ] and octahedral [Sn/ Mg−O 6 ] sites, giving rise to a broadband NIR emission spanning 720−789 nm. On account of energy-level alignment, the electrons released from the traps show a preferential return to the excited energy level of Fe 3+ in tetrahedral sites through tunneling, leading to a single-peak NIR afterglow centered at 789 nm with a full-width at half-maximum (fwhm) of 140 nm. The highefficiency NIR afterglow, showing a record persistent time lasting over 31 h among Fe 3+ -based phosphors, is demonstrated as a self-sustainable light source for night vision applications. This work not only provides a novel Fe 3+ -doped high-efficiency NIR afterglow phosphor for technological applications but also establishes practical guidance for rational tuning of afterglow emissions.

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“…Accompanied with illumination, a higher g-value (g≈3. 8) signal was observed at 100-200 mT (defined as Mn 4+ ), which was in sharp contrast to the signal under dark condition 23 . This phenomenon demonstrates that photo-radiation could promote the transformation of low-valence manganese (Mn 2+ , including partial Mn 3+ ) to high-valence manganese (Mn 4+ ).…”

Section: Photoelectrochemical Coupling Mechanismmentioning

confidence: 76%

Stable aqueous aluminum-manganese photoelectrochemical cells with high-rate and high-efficiency abilities

Jiao

Zhang

Song

et al. 2021

Preprint

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Aqueous aluminum-ion batteries (AAIBs) are potential candidates for large-scale energy storage devices for their advantages of high energy density, resource abundance, low cost, safety, and environmental friendliness. Due to various redox procedures, good reversibility, and high discharge potential, the aqueous aluminum-manganese oxide battery has drawn wide attention, while the critical issues induced from slow kinetics and undesired soluble Mn2+ lead to slow charging, poor rate capability, and low energy density. However, there is very limited progress for performance improvement via conventional chemical or physical modification approaches. To overcome these challenges, an efficient photo-regulation strategy has been proposed in terms of direct radiating visible light on the cell during the galvanostatic charging and discharging. The efficient separation and transmission of photoelectrons in the photo positive electrode dramatically improves the dynamics, and fast charging and enhanced rate performance could be achieved. Photo-oxidation behavior can effectively promote the conversion of soluble Mn2+, thus further enhancing the energy density of the as-assembled aluminum-manganese battery. Furthermore, a photo-conversion efficiency of up to 1.2% has been acquired. Based on the photo-regulation strategy, the mechanism of the photoelectrochemical coupling system has been understood, which opens a promising route for achieving photoelectrochemical batteries with high energy density and fast charge.

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The effect of electron cloud expansion on the red luminescence of Sr4Al14O25:Mn4+ revealed by calculation of the Racah parameters

Cited by 41 publications

References 23 publications

Enhancing the Photocatalytic Activity of Sr₄Al₁₄O₂₅: Eu²⁺, Dy³⁺ Persistent Phosphors by Codoping with Bi³⁺ Ions

Enhancing the Photocatalytic Activity of Sr₄Al₁₄O₂₅: Eu²⁺, Dy³⁺ Persistent Phosphors by Codoping with Bi³⁺ Ions

Near-Infrared Long Afterglow in Fe³⁺-Activated Mg₂SnO₄ for Self-Sustainable Night Vision

Stable aqueous aluminum-manganese photoelectrochemical cells with high-rate and high-efficiency abilities

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The effect of electron cloud expansion on the red luminescence of Sr4Al14O25:Mn4+ revealed by calculation of the Racah parameters

Cited by 41 publications

References 23 publications

Enhancing the Photocatalytic Activity of Sr4Al14O25: Eu2+, Dy3+ Persistent Phosphors by Codoping with Bi3+ Ions

Enhancing the Photocatalytic Activity of Sr4Al14O25: Eu2+, Dy3+ Persistent Phosphors by Codoping with Bi3+ Ions

Near-Infrared Long Afterglow in Fe3+-Activated Mg2SnO4 for Self-Sustainable Night Vision

Stable aqueous aluminum-manganese photoelectrochemical cells with high-rate and high-efficiency abilities

Contact Info

Product

Resources

About

Enhancing the Photocatalytic Activity of Sr₄Al₁₄O₂₅: Eu²⁺, Dy³⁺ Persistent Phosphors by Codoping with Bi³⁺ Ions

Enhancing the Photocatalytic Activity of Sr₄Al₁₄O₂₅: Eu²⁺, Dy³⁺ Persistent Phosphors by Codoping with Bi³⁺ Ions

Near-Infrared Long Afterglow in Fe³⁺-Activated Mg₂SnO₄ for Self-Sustainable Night Vision