Luminescent lanthanide single atom composite materials: Tunable full-color single phosphor and applications in white LEDs

ACS Appl. Electron. Mater.

Lei

et al. 2022

In the present investigation, we demonstrated a simple approach for the reproducible synthesis of cerium(III)-based blue phosphor, which provides versatile applications in the construction of warm white-light-emitting diodes (WLEDs) and anticounterfeiting patterns. It is found that the mixture of dipicolinic acid (DPA) with Ce3+ in ethanol (DPA-Ce) emits blue fluorescence under the assistance of ultraviolet (UV) induction. The quantum yield of the DPA-Ce phosphor reaches 44% and is improved to 52% by combining with guanosine 5′-monophosphate (GMP). The obtained DPA-Ce-GMP emits blue fluorescence in both a solid powder and aqueous solution, having advantages of long luminescence lifetimes, ultralong stability, and outstanding antitemperature bleaching. With DPA as a universal ligand, DPA-Tb with green fluorescence and DPA-Eu with red fluorescence are integrated with the blue fluorescence of DPA-Ce-GMP to construct full-color and white-light-emitting devices. The as-prepared warm WLED with a quantum yield of 64% presents an excellent stability and high quality with a color rending index of up to 90, CIE color coordinates of (0.37, 0.36), a correlated color temperature of 3950 K, and a luminous efficiency of 37.8 lm W–1. Multiple anticounterfeiting patterns are further encoded with the as-prepared lanthanide-based phosphors. The investigation offers a simple assay for the cost-effective, large-scale synthesis of phosphors, with great promise in diverse applications including the lighting industry and anticounterfeiting technology.

Section: Resultsmentioning

confidence: 99%

Efficient One-Pot Synthesis of Bright Blue-Emitting Ce³⁺-Based Phosphor: Application for the Construction of Warm White-Light-Emitting Diodes and Anticounterfeiting

ACS Appl. Electron. Mater.

Lei

et al. 2022

“…The XRD patterns of the MOFEu 3+ are consistent with the reported results. [47,48] The UV-vis absorption and emission spectra (λ ex = 360 nm) of samples with different Na 2 CO 3 content are shown in Figure 5b,c. It is noted that the emission spectra of the MOF Eu 3+ and MOFTb 3+ are also shown in Figure S4 (Supporting Information), which will be used in WLED devices later.…”

Section: Structural and Morphological Characterizationsmentioning

confidence: 99%

CsPbBr₃:Na with an Adjustable Bandgap, Improved Luminescence Stability, and its Application in WLEDs with Excellent Color Quality and Vision Performance

Sun

et al. 2022

Adv Funct Materials

Self Cite

It is still a great challenge to obtain multicolor tunable luminescence and improve the stability of luminescence through reasonable design of materials in the field of white light-emitting diodes (WLEDs). In particular, it is more important to improve the luminescence intensity and stability of blue-emitting materials. Here, the properties of CsPbBr 3 , CsPbBr 3 :Na , and NaPbBr 3 are investigated theoretically by using density functional theory (DFT). Based on the DFT theoretical calculation results, it is assumed that unexpected performance may be achieved by replacing Cs in CsPbBr 3 with Na or passivating the surface of CsPbBr 3 with Na. As expected, the tunable luminescence from blue to green is successfully achieved from CsPbBr 3 :Na, and the stability is improved. After experimental optimization, the obtained CsPbBr 3 :Na (CPBN-4) with high luminescence stability is used as blueemitting materials to construct the WLED devices with excellent color quality (CRI 92) and correlated color temperature of 9582 K.

“…Metal–organic frameworks (MOFs) have emerged as promising candidates for fluorescent materials, owing to their unique structural features. − MOFs are porous crystalline materials composed of metal ions/clusters and organic ligands, so the fluorescence can originate from the emission of metal nodes, ligands, or/and inclusive guest molecules. − Since the first report on WLE MOFs in 2009, the research of WLE materials based on MOFs has become a hotspot. − So far, quite a few methods and strategies for preparing SPWLE MOFs have been reported, which can be summarized as follows: (1) direct synthesis; (2) rare-earth ion doping; − (3) multivariate MOFs (MTV MOFs); (4) encapsulation of rare-earth ion guests, − yellow-emitting guests, or green- and red-emitting guests into blue-emitting MOFs; and (5) introduction of blue-, green-, and red-emitting guests into three-dimensional (3D) porous MOFs . The first three synthetic methods are based on the self-WLE MOFs: the direct combination of metals and ligands to construct white light MOFs is difficult to design and predict; the central rare-earth ion doping method has certain designability, but the types and quantities of rare-earth MOFs are limited; the method of MTV MOFs is straightforward but difficult because it is necessary to not only organically assemble the red-, green-, and blue-emitting ligands but also precisely control the proportion of each component.…”

Section: Introductionmentioning

confidence: 99%

Introduction of Multicomponent Dyes into 2D MOFs: A Strategy to Fabricate White Light-Emitting MOF Composite Nanosheets

Liang

ACS Appl. Mater. Interfaces

et al. 2023

Metal–organic frameworks (MOFs) have been extensively studied in host–guest chemistry by means of ultrahigh porosities, tunable channels, and component diversities. As the host matrix, MOFs exhibit immense potential in the preparation of single-phase white light-emitting (SPWLE) materials. Nonetheless, it is a great challenge that the size of the introduced guest molecules is limited by MOF pores, which affects the WLE optimization. In this work, two-dimensional (2D) MOFs are first utilized as the host matrices to simultaneously encapsulate red–green–blue fluorescent dyes for SPWLE. Various dyes@2D MOF composites with high-quality WLE performances and ultrathin nanosheet morphologies are directly assembled from 2D MOF precursors and dyes in high yields. Owing to the flexible interlamellar space of 2D MOFs, different types and sizes of guests can be easily introduced, which greatly expands the range of available MOF hosts and guests, making the WLE much more tunable. The strategy of employing 2D MOFs as the host matrices to introduce multicomponent dyes for SPWLE nanosheets resolves the restriction of MOF pores on the guest molecule size and opens a new avenue to rationally design and prepare SPWLE nanosheets that are highly solution-processable.