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In this review we will present several research papers pertaining to white colour (or other) emission from Dy3+ doped and undoped phosphor materials. The search for a single component phosphor material that could deliver high quality white light under UV or near UV excitation is an area of active research for commercial purposes. Amongst all rare earth elements Dy3+ is the only ion that could deliver simultaneously blue and yellow light under UV excitation. In optimizing the Yellow/Blue emission intensity ratios, white light emission can be realized. Dy3+ (4f9) displays approximately 4 emission peaks at around 480 nm, 575 nm, 670 and 758 nm corresponding to transitions from the metastable 4F9/2 state to various lower states, such as 6H15/2 (blue), 6H13/2 (yellow), 6H11/2 (red) and 6H9/2 (brownish red), respectively. In general, the hypersensitive transition at 6H13/2 (yellow) is electric dipole in nature and becomes prominent only when Dy3+ ions are positioned at low symmetric sites with no inversion symmetry in the host matrix. On the other hand, the blue magnetic dipole transition at 6H15/2 becomes prominent only when Dy3+ ions are positioned at highly symmetric sites in the host material with inversion symmetry. Despite the white colour emission from the Dy3+ ions, these transitions are mainly associated with parity forbidden 4f -4f transitions, the white light produced maybe diminished at times, hence the need to include a sensitizer to bolster the forbidden transitions experienced by Dy3+ ions. In this review we will focus on the variability of the Yellow/Blue emission intensities in different host materials (phosphates, silicates, and aluminates) from Dy3+ ions (doped or undoped) by studying their photoluminescent properties (PL), their CIE chromaticity coordinates and correlated colour temperature (CCT) values for white colour emissions that is adaptable to different environmental conditions. [ABSTRACT FROM AUTHOR]

Iron-doped Zinc oxide nanoparticles were produced by the sol-gel combustion method. This study aims to see how iron doping affects the structural, optical, and photocatalytic characteristics of ZnO composites. XRD examined all samples to detect the structural properties and proved that all active materials are a single hexagonal phase. The morphology and particle size were investigated by TEM. Computational Density functional theory (DFT) calculation of the band structure, density of state, and charge distributions for ZnO were investigated in comparison with ZnO dope iron. We reported the application results of ZnO doped Fe for Methylene blue dye removal under photocatalytic degradation effect. The iron concentrations affect the active material's band gap, producing higher photocatalytic performance. The acquired results could be employed to enhance the photocatalytic properties of ZnO. [ABSTRACT FROM AUTHOR]

The doping method is considered a proficient technique for enhancing the photocatalytic performance of nanostructures. Herein, doping of Mn into the V 2 O 5 (VO) nanostructure increased their photodegradation capacity toward malachite green dye (MG). Different physical strategy to investigate the physiochemical behavior of the undoped and Mn doped V 2 O 5. Using an aqueous malachite green (MG) solution and xenon light illumination, the degradation capabilities of the manufactured pristine and Mn doped V 2 O 5 were studied. The pristine V 2 O 5 and Mn doped V 2 O 5 nanoarray display a photocatalytic efficiency of 94.79 % for MG compared to the pure V 2 O 5 (75.52 %). Consistently, doping of Mn into V 2 O 5 was shown to affect the photodegradation of malachite green significantly. Our finding suggests that Mn doped V 2 O 5 nanomaterials act as potential photocatalysts to degrade the MG dye and can act as an environmental cleaner to resolve the other related issues. • The doping strategy was employed to increase the photocatalytic efficiency of V 2 O 5 (VO) for MG dye. • The Mn doped VO exhibited the high photocatalytic efficiency of 94.79 % and recycling ability of 87.13 % over 5th cycles. • The holes, oxygen and hydroxyl radical play a great role in mineralization of MG dyes. [ABSTRACT FROM AUTHOR]

By employing time‐dependent density functional theory for solid‐state chemistry, the research presented by Andrii Shyichuk [Acta Cryst. (2023), B67, 437–449] significantly contributes to the understanding of electron/hole traps in doped materials. [ABSTRACT FROM AUTHOR]

Doped single‐phase materials have been widely investigated owing to their easy to implement synthesis and the variety of their properties. This Minireview covers strategies for the co‐stabilization and the ratio control of several oxidation states of dopants inserted in the same host. The tuning of the oxidation states of dopants opens up many possibilities for the optimization of specific properties and can be envisioned for various applications such as telecommunication, medicine, displays, lasers or lighting. Technics used for the quantification of each valence state of dopant are also emphasized, and the importance of high throughput methods for the discovery of efficient materials with dopants in multiple valence states is discussed. [ABSTRACT FROM AUTHOR]