Blue-shifted Spectrum Research Articles

Spheres-in-Grating Assemblies with Altered Photoluminescence and Wetting Properties.

In this work, we report the fabrication of spheres-in-grating assemblies consisting of equally spaced parallel rectangular grooves filled with fluorescent spheres, by employing embossing and convective self-assembly methods. The developed hierarchical assemblies, when compared to spheres spin-cast on glass, exhibited a blueshift in the photoluminescence spectra, as well as changes in wetting properties induced not only by the patterning process, but also by the nature and size of the utilized spheres. While the patterning process led to increased hydrophobicity, the utilization of spheres with larger diameter improved the hydrophilicity of the fabricated assemblies. Finally, by aiming at the future integration of the spheres-in-grating assemblies as critical components in different technological and medical applications, we report a successful encapsulation of the incorporated spheres within the grating with a top layer of a functional polymer.

Investigation of 4,4′-bis[(N- carbazole) styryl] biphenyl (BSB4) for a pure blue fluorescent OLED with enhanced efficiency nearing the theoretical limit

4,4′-bis[(N-carbazole) styryl] biphenyl (BSB4 or BSBCz) is one of the widely studied organic fluorescent materials for blue organic electroluminescent devices in the recent times. In this work, BSB4 is used as a guest material to construct the host-guest matrix for the emissive layer (EML) of a pure blue fluorescent organic light-emitting diode (OLED). A pure blue emission suitable for display application with a Commission Internationale de l’Eclairage coordinate of (0.147,0.070) is achieved by the blue-shift of the emission spectrum of the host-guest matrix from that of the pristine guest (BSB4) molecules. The optimization of OLED structures is carried out by considering (a) charge balance in the EML for high exciton density, and (b) optical interference of generated light in the organic layers for increased light outcoupling. A thorough comparative study on the use of different combinations of widely used hole and electron transport layers to obtain charge balance in the EML of the OLED, thereby enhancing the external quantum efficiency (EQE) is shown. Optical interference effects in the fabricated OLEDs are analyzed by optical simulation of each device structure by transfer matrix method. With the optimized device structures, we are able to overcome the 2% EQE limit that has been reported so far for blue fluorescent OLEDs with BSB4 as light emitting material and achieve a maximum EQE of 4.08%, which is near to the theoretical limit of EQE for fluorescent OLEDs.

Diluted exciplex concentrations in organic light emitting diodes for blue-shifted spectra and improved efficiency

Diluting exciplex concentrations by adjusting the acceptor ratio or inserting a spacer in organic light emitting diodes for achieving blue-shifted spectra and improved efficiency.

The Dog That Didn't Bark: A New Interpretation of Hypsoporphyrin Spectra and the Question of Hypsocorroles.

Nearly a half-century after Gouterman classified the UV–vis–NIR spectra of porphyrin derivatives as normal, hyper, or hypso, we propose a heretofore unsuspected “mechanism” underlying hypso spectra. Hypsoporphyrins, which exhibit blueshifted optical spectra relative to normal porphyrins (such as Zn porphyrins), typically involve dn transition metal ions, where n > 6. The spectral blueshifts have been traditionally ascribed to elevated porphyrin eg LUMO (lowest unoccupied molecular orbital) energy levels as a result of antibonding interactions with metal dπ orbitals. Herein, we have found instead that the blueshifts reflect a lowering of the a2u HOMO (highest occupied molecular orbital) energy levels. Electronegative metals such as Pd and Pt transfer smaller quantities of electron density to the porphyrin nitrogens, compared to a more electropositive metal such as Zn. With large amplitudes at the porphyrin nitrogens, the a2u HOMOs of Pd(II) and Pt(II) porphyrins accordingly exhibit lower orbital energies than those of Zn(II) porphyrins, thus explaining the hypso effect. Hypso spectra are also observed for corroles: compared with six-coordinate Al(III) corroles, which may be thought of exhibiting normal spectra, Au(III) corroles, for instance, exhibit blueshifted or hypso spectra.

Molecular engineering of the fused azacycle donors in the D-A-π-A metal-free organic dyes for efficient dye-sensitized solar cells

Four novel D-A-π-A metal-free organic sensitizers QL1–4 with the fused azacycle units as donors have been designed and synthesized to investigate the relationship between both the sizes and conjugations of azacycle and performances of dye-sensitized solar cells systematically. QL1 with the five-membered azacycle, i.e., with carbazole (Cz) as donor, exhibits the smallest molar extinction coefficients (ε). QL2 and QL3 with the seven-membered azacycle, i.e. with N-phenyl-iminostilbene (ISB) and N-phenyl-iminodibenzyl (IDB) as donors, respectively, show the red-shifted absorption spectra and higher ε compared to QL1. However, QL2 and QL3 with an only distinction in a single or double bond, display distinctive PCEs. QL4 with the six-membered azacycle, i.e., 9,9,10-triphenyl-9,10-dihydroacridine (TDD), exhibits a blue-shifted absorption spectrum due to a big dihedral angle, resulting in a lower photovoltaic performance. Especially, QL3 with the ISB donor is conducive to achieving a PCE of 6.22%, which is higher than QL2, due to its better planar structure and more conjugation. When co-adsorbed with CDCA, QL3 exhibits the highest PCE of 7.14% among all dyes, and up to 8.26% by co-sensitizing with dye WL5, which surpasses that of the reference dye N719 (7.75%). The results indicate that the size and conjugation of the fused azacycle donors may affect the photovoltaic performance significantly, and the ISB unit is demonstrated as a promising donor for efficient organic dyes.

Multi-peak narrow-band perfect absorber based on two-dimensional graphene array

In this paper, we have investigated an absorber based on two-dimensional hexagonal graphene array and theoretically propose a calculation method for the approximate conductivity of graphene in the terahertz band and its correction term, and we also theoretically explain the phenomenon of blue-shift of the absorption spectrum with increasing graphene chemical potential. The finite difference time domain (FDTD) method shows that this absorber has the advantages of exciting high absorption rate, multi-band, tunable and high figure of merit (FOM). By discussing the analysis of different graphene geometries, we demonstrate the optimality of this result. The bottom layer of our absorber is composed of an Au reflection layer, and the middle layer is a silicon oxide dielectric layer. Four hexagonal two-dimensional graphene is placed at the top. Taking this as the basic unit, an array can be formed. Our absorber has a simple structure, which simplified the processing technology and saves the processing cost greatly. In the near-infrared band from 1600 nm to 1900 nm, our absorbers have absorption peaks of 99.70%, 99.25% and 99.82% at 1667.19 nm, 1691.71 nm and 1773.20 nm, respectively. In addition, the resonance wavelength of the absorber can also be adjusted by adjusting the chemical potential and refractive index of the silicon dioxide layer. The absorber also has the features of polarization and angular insensitivity. Our simulation results show that our absorber's absorption spectrum will change significantly as the ambient refractive index changes, and based on this, we can calculate the sensitivity and the figure of merit (FOM) of our model. We finally calculated the best FOM for the three peaks of our absorber (sorted by resonance wavelength from short to long) is 90.93, 90.96, 107.34, and the sensitivity is 290.25 nm/RIU, 309.95 nm/RIU, 318.50 nm/RIU, respectively. Thus, we trust that our absorbers can be widely used in Near-infrared thermal radiation, optical detector and Near-infrared sensors.

Improvement of high-order harmonics from silver plasma plumes induced by femtoseconds laser pulses

Silver plasma plume is one of the potential sources for high-order harmonics generation (HHG) using a driving pulse of 800 nm (Ti: S laser system). The harmonic intensity (yield) and cut-off are significantly affected by ablating laser pulse duration. This work extended the harmonics generation using silver [bulk and nanoparticles (100 nm and 20 nm)] plasma plumes ablated by fs laser pulses. The shorter pulse duration of fs pulses leads to enhanced ions' density, which improves the harmonics' intensity and cut-off (65H). Moreover, the experimental harmonic cut-off for Ag+ is precisely matched with the theoretical cut-off. In Ag2+ ions, the experimental cut-off is ∼1.3 times less than the theoretical cut-off. In addition, we have measured the harmonic spectra of samples using negatively and positively chirped 135 fs driving pulses and compared them with chirp-free 35 fs driving pulse harmonic spectra. The negative and positive chirps of the pulses lead to blueshift and redshift of the harmonic's spectra, with an increase of intensity of low (9H–15H) and higher (17H–41H) range harmonics, respectively. However, the comparison between bulk and nanoparticles (NPs) studies proved that the smallest NPs possess larger HHG efficiency. The present study highlights the selection of short pulse duration, i.e., fs pulses as driving and ablating laser pulses, for enhancing the yield and cut-off of harmonics for next-generation table-top XUV light sources.

Action spectroscopy of the isolated red Kaede fluorescent protein chromophore.

Incorporation of fluorescent proteins into biochemical systems has revolutionized the field of bioimaging. In a bottom-up approach, understanding the photophysics of fluorescent proteins requires detailed investigations of the light-absorbing chromophore, which can be achieved by studying the chromophore in isolation. This paper reports a photodissociation action spectroscopy study on the deprotonated anion of the red Kaede fluorescent protein chromophore, demonstrating that at least three isomers-assigned to deprotomers-are generated in the gas phase. Deprotomer-selected action spectra are recorded over the S1 ← S0 band using an instrument with differential mobility spectrometry coupled with photodissociation spectroscopy. The spectrum for the principal phenoxide deprotomer spans the 480-660nm range with a maximum response at ≈610nm. The imidazolate deprotomer has a blue-shifted action spectrum with a maximum response at ≈545nm. The action spectra are consistent with excited state coupled-clustercalculations of excitation wavelengths for the deprotomers. A third gas-phase species with a distinct action spectrum is tentatively assigned to an imidazole tautomer of the principal phenoxide deprotomer. This study highlights the need for isomer-selective methods when studying the photophysics of biochromophores possessing several deprotonation sites.

Effective Disposal of Methylene Blue and Bactericidal Benefits of Using GO-Doped MnO2 Nanorods Synthesized through One-Pot Synthesis.

Graphene oxide (GO)-doped MnO2 nanorods loaded with 2, 4, and 6% GO were synthesized via the chemical precipitation route at room temperature. The aim of this work was to determine the catalytic and bactericidal activities of prepared nanocomposites. Structural, optical, and morphological properties as well as elemental composition of samples were investigated with advanced techniques such as X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, UV–visible (vis) spectroscopy, photoluminescence (PL), energy-dispersive spectrometry (EDS), and high-resolution transmission electron microscopy (HR-TEM). XRD measurements confirmed the monoclinic structure of MnO2. Vibrational mode and rotational mode of functional groups (O–H, C=C, C–O, and Mn–O) were evaluated using FTIR results. Band gap energy and blueshift in the absorption spectra of MnO2 and GO-doped MnO2 were identified with UV–vis spectroscopy. Emission spectra were attained using PL spectroscopy, whereas elemental composition of prepared materials was recorded with scanning electron microscopy (SEM)-EDS. Moreover, HR-TEM micrographs of doped and undoped MnO2 revealed elongated nanorod-like structure. Efficient degradation of methylene blue enhanced the catalytic activity in the presence of a reducing agent (NaBH4); this was attributed to the implantation of GO on MnO2 nanorods. Furthermore, substantial inhibition areas were measured for Escherichia coli (EC) ranging 2.10–2.85 mm and 2.50–3.15 mm at decreased and increased levels for doped MnO2 nanorods and 3.05–4.25 mm and 4.20–5.15 mm for both attentions against SA, respectively. In silico molecular docking studies suggested the inhibition of FabH and DNA gyrase of E. coli and Staphylococcus aureus as a possible mechanism behind the bactericidal activity of MnO2 and MnO2-doped GO nanoparticles (NPs).

Tunable broadband emission by bandgap engineering in (Ba,Sr)2(Mg,Zn)WO6 inorganic double-perovskites

Four tungstate double-perovskite materials with a general formula A2BWO6, where A=Ba, Sr and BMg, Zn were synthesized by co-precipitation method. All samples exhibit blue emission under UV excitation resulting from the additional electron states within the material’s band gap created by two types of centers: the regular and the inversion tungstate groups. The latter one is defined as a W6+ ion residing at the octahedral B site (B = Mg, Zn). The relative position of those two centers’ energy levels to the valence and conduction bands can be altered by the substitution to the A site (Ba/Sr) as well as the B site (Mg/Zn). Substitution of Sr for Ba results in a blue-shift of both excitation and emission spectrum. The substitution of Zn for Mg, in contrast, results in the opposite phenomenon. The substitutions, aside from shifting the emission wavelength of the centers, regulate the ratio between regular and inversion tungstate groups by restricting or allowing the energy transfer between them and influence their thermal stability. The luminescence properties are in agreement with the DFT calculations. The ability to influence their host emission wavelength, intensity, and thermal stability can be crucial in the design of novel luminescent thermometers.

Positive temperature dependence of the electroluminescent performance in a colloidal quantum dot light-emitting diode

In this study, the temperature dependence of the dynamic behavior in colloidal quantum dot light-emitting diodes (QLEDs) in a wide temperature range (120 K–300 K) is investigated. The results demonstrate that the electroluminescent performance of the device is enhanced as the temperature rises. Particularly, the device current efficiency is improved and the turn-on voltage is lowered. In addition, the decline in temperature results in a blue-shift of the electroluminescence spectrum. Consequently, the charge injection barrier is studied using thermionic emission model and impedance spectroscopy, and the results show that this injection barrier increases when the temperature is elevated, leading to more difficult charge injection. Meanwhile, the charge transport study proves that the average charge lifetime in the device is prolonged at higher temperature, which is beneficial for the transport of charges. Furthermore, the analyses of the trap states and their distribution reveal that more trap states exist at low temperature, causing performance degradation in the device. The analysis and discussion in this work provide fundamental insights into the working mechanism of QLEDs and can be used to predict device performance under extreme operating conditions.

A rational design of multimodal asymmetric nanoshells as efficient tunable absorbers within the biological optical window

In this work, the optical properties of asymmetric nanoshells with different geometries are comprehensively investigated in the quasi-static regime by applying the dipolar model and effective medium theory. The plasmonic behaviors of these nanostructures are explained by the plasmon hybridization model. Asymmetric hybrid nanoshells, composed of off-center core or nanorod core surrounded by a spherical metallic shell layer possess highly geometrically tunable optical resonances in the near-infrared regime. The plasmon modes of this nanostructures arise from the hybridization of the cavity and solid plasmon modes at the inner and outer surfaces of the shell. The results reveal that the symmetry breaking drastically affects the strength of hybridization between plasmon modes, which ultimately affects the absorption spectrum by altering the number of resonance modes, their wavelengths and absorption efficiencies. Therefore, offsetting the spherical core as well as changing the internal geometry of the nanoparticle to nanorod not only shift the resonance frequencies but can also strongly modify the relative magnitudes of the absorption efficiencies. Furthermore, higher order multipolar plasmon modes can appear in the spectrum of asymmetric nanoshell, especially in nanoegg configuration. The results also indicate that the strength of hybridization strongly depends on the metal of shell, material of core and the filling factor. Using Au-Ag alloy as a material of the shell can provide red-shifted narrow resonance peak in the near-infrared regime by combining the specific features of gold and silver. Moreover, inserting a high permittivity core in a nanoshell corresponds to a red-shift, while a core with small dielectric constant results in a blue-shift of spectrum. We envision that this research offers a novel perspective and provides a practical guideline in the fabrication of efficient tunable absorbers in the nanoscale regime.

Tunability in the terahertz range of a one-dimensional photonic quasicrystal containing an InSb semiconductor

In this study, we calculate the transmittance spectrum of a one-dimensional photonic quasicrystal composed of SiO2 and an extrinsic InSb semiconductor. The layers of materials are arranged as per the Octonacci sequence. When using the transfer matrix method, the transmittance spectrum is tuned, by a variation in the temperature, the doping concentration, and the thicknesses of materials. At fixed values of the Octonacci sequence, we find that the fractal photonic band gap and the quasi-localized states exhibit a shift to higher frequencies when temperature increases. The blue-shift of the transmittance spectrum is obtained when the doping concentration is increased.

Single-laser-based simultaneous four-wavelength excitation source for femtosecond two-photon fluorescence microscopy.

Multicolor labeling of biological samples with large volume is required for omic-level of study such as the construction of nervous system connectome. Among the various imaging method, two photon microscope has multiple advantages over traditional single photon microscope for higher resolution and could image large 3D volumes of tissue samples with superior imaging depth. However, the growing number of fluorophores for labeling underlines the urgent need for an ultrafast laser source with the capability of providing simultaneous plural excitation wavelengths for multiple fluorophores. Here, we propose and demonstrate a single-laser-based four-wavelength excitation source for two-photon fluorescence microscopy. Using a sub-100 fs 1,070-nm Yb:fiber laser to pump an ultrashort nonlinear photonic crystal fiber in the low negative dispersion region, we introduced efficient self-phase modulation and acquired a blue-shifted spectrum dual-peaked at 812 and 960 nm with 28.5% wavelength conversion efficiency. By compressing the blue-shift near-IR spectrum to 33 fs to ensure the temporal overlap of the 812 and 960 nm peaks, the so-called sum frequency effect created the third virtual excitation wavelength effectively at 886 nm. Combined with the 1,070 nm laser source as the fourth excitation wavelength, the all-fiber-format four-wavelength excitation source enabled simultaneous four-color two-photon imaging in Brainbow AAV-labeled (TagBFP, mTFP, EYFP, and mCherry) brain samples. With an increased number of excitation wavelengths and improved excitation efficiency than typical commercial femtosecond lasers, our compact four-wavelength excitation approach can provide a versatile, efficient, and easily accessible solution for multiple-color two-photon fluorescence imaging in the field of neuroscience, biomolecular probing, and clinical applications with at least four spectrally-distinct fluorophores.

Guest-Regulated Luminescence and Force-Stimuli Response of a Hydrogen-Bonded Organic Framework.

Guest molecules may endow porous materials with new or enhanced properties as well as functions. Here, a porous hydrogen-bonded organic framework (HOF) constructed from a three-armed triphenylamine derivative is used to investigate how guests regulate photoluminescence and trigger force-stimuli response. It was found that guest solvents in pores might regulate HOF's luminescence. Interestingly, acetic acid as a guest endowed HOF materials with longer emission wavelengths and triggered the responses to mechanical force stimuli. Under shear force, an obvious blueshift in emission spectra was observed because of the loss of free guests and the conversion of π-stacking model. Further blue-shifted emission appeared while the bound guests were completely removed by heating. Mechanofluorochromic HOF materials could be regenerated through recrystallization and adsorbing guest. Conversely, HOFs with other guests and activated HOFs only resulted in a slight change in their fluorescence behaviors after force stimuli.

Transport properties of thermally stable conducting poly(aniline-co-m-hydroxyaniline)

Uniform dielectric permittivity of hollow and porous semiconducting copolymer poly(aniline-co-m-hydroxyaniline) (PA-co-m-HA)s has been studied by electrochemical impedance spectroscopy. The copolymer is obtained by the in- situ processing of the monomers, viz, aniline and 2-hydroxyaniline using ammonium persulfate (APS) as an oxidizing agent. The extent of the π-conjugated system or the bandgap of the highest occupied molecular orbitals (HOMO) and the lowest unoccupied molecular orbitals (LUMO) has been studied by electronic spectroscopy considering the blue-shift in the optical spectra. The frequency-dependent uniform ac conductivity has been noticed. Globular and porous morphology has been studied by scanning electron microscopy (SEM). Reduced crystallinity of the copolymers has been confirmed by X-ray diffraction and DSC analysis. The electrochemical performance of the material is studied by cyclic voltammetry.

Anomalous photoluminescence properties of emissive polymer originating from modulated chemical structures affected by antioxidant effect of natural β-carotene

We investigated the antioxidant effect of natural β-carotene on the photoluminescence (PL) properties of emissive polymers and extracted the β-carotene from spinach using column chromatography. The follow-up observation of the PL spectra of β-carotene-doped poly[2-methoxy-5-(3′,7′-dimethyloctyloxy)-1,4-phenylenevinylene] (MDMO-PPV) revealed anomalous properties; the PL intensity gradually increased. In addition, the PL peaking-wavelength was blue-shifted. To evaluate this phenomenon, we performed nuclear magnetic resonance (NMR) and PL measurements of other two emissive polymers whose chemical structures resemble those of MDMO-PPV. MDMO-PPV and β-carotene were mixed in the solution for the NMR measurement and irradiated by UV to accelerate the chemical reactions. NMR measurement clearly shows that the chemical structure of MDMO-PPV was changed by β-carotene-doping. In particular, the conjugated double-bond structure of the main chain backbone was shortened by the cleavage of the alkene, breaking the side chains of the methoxy groups. Thus, the origin of the blue-shifted PL spectra can be attributed to these changes in the MDMO-PPV’s chemical structure. To confirm this, the PL properties of MDMO-PPV and two other β-carotene-doped emissive polymers in oxygen gas were evaluated. Their PL intensities exhibited similar increases, but their peaking-wavelengths were not blue-shifted. This indicates that although β-carotene can improve the PL lifetime of emissive polymers, the chemical structures of some polymers can be easily destroyed.

Understanding the Effect of Sequential Deposition Processing for High-Efficient Organic Photovoltaics to Harvest Sunlight and Artificial Light.

As the market of the Internet of Things (IoT) increases, great attention has been paid to the development of high-efficient organic photovoltaics (OPVs) utilizing artificial light. However, in a real indoor condition, the power density contribution of the artificial light cannot exceed 35% in the combination of indoor and outdoor irradiation, which indicates that the illumination of sunlight cannot be ignored during daytime. Hence, it is urgent to develop high-efficient OPVs in indoor conditions taking into account both sunlight and artificial light. In this work, a novel asymmetric molecule TB-4F was synthesized to trade-off the absorption spectrum that can be applied under both artificial light and sunlight. In conventional bulk-heterojunction (C-BHJ), it was figured out that due to nonoptimal morphology some carriers failed to be efficiently collected. Herein, a sequential deposition bulk-heterojunction (SD-BHJ) as an alternative fabrication method successfully enhanced the performance of OPVs, under both artificial light and sunlight, which was attributed to the favorable microstructure being vertically distributed in the active layer. Notably, the PCE was significantly increased by 25% for SD-BHJ compared to C-BHJ under artificial light, owing to the strong effect of trap-assisted recombination and dark current on PCE in the condition of low carrier density. Our result indicates that an asymmetric molecule with a blue-shifted spectrum fabricated by SD-BHJ can be a promising candidate that can be applied in indoor environments to harvest sunlight and artificial light simultaneously.

Enhancing the photovoltaic performance with two similar structure polymers as donors by broadening the absorption spectrum and optimizing the molecular arrangement

Ternary organic photovoltaics (OPVs) were fabricated with two polymers (PM6 and D18) as the donor and the fullerene-free small molecule Y6 as the acceptor in an inverted structure. The blueshifted absorption spectrum of neat D18 relative to neat PM6 can enable harvesting of more short and medium wavelength photons in the ternary photoactive layer, which is beneficial to increasing the short-circuit current density ( J SC ). The enhancement of the open-circuit voltage ( V OC ) of the ternary OPVs can be explained by the deeper HOMO level of D18 than that of PM6, which is beneficial to broadening the energy bandgap. In addition, the combination of the cascade LUMO levels among D18, PM6 and Y6 and the enhanced crystallinity can lead to more efficient exciton dissociation and charge transport within the ternary films. As a result, the power conversion efficiency of the optimize ternary OPV is 15.85%, which is higher than those of the PM6:Y6- and D18:Y6-base binary OPVs (PCEs of 14.70% and 14.95%, respectively). The results indicate that ternary OPVs with a blend of two similar chemical structure polymers as the donor could achieve high performance by broadening the light spectrum and optimizing the phase separation and crystallinity. • D18 plays a dominant role in the light absorption and exciton dissociation. • The separation of exciton of D18 mainly occurs on the D18/PM6 interface. • The OPV based on D18 as third component materials exhibit a significant increase of 10% in PCE.

Preparation and characterization of Gd3(ScAl)2Al3O12:Ce3+ garnet phosphors towards high-color-rendering white-light illumination

The design and development of phosphors have received widespread attention with the increasing demand for white light-emitting diodes (WLEDs). In this work, a series of Ce3+-doped gadolinium scandium aluminum garnet (GSAG) phosphors were successfully synthesized by the sol-gel method, and the relevant structural, optical, and lighting properties were investigated in detail. The optimal sintering process was optimized to 1873 K for 5 h under an Ar/H2 reduction atmosphere, and the structural analysis showed that the lattice parameters were gradually increased with an increase in Sc/Al substitution. The cationic substitution of GSAG adjusted the local coordination environments of Ce3+ ions effectively, and the increasing Sc3+-doped concentrations gave rise to a blue-shift of photoluminescence spectra and a decline of related fluorescence lifetimes. Furthermore, the doping concentration of Ce3+ ions was optimized and the concentration quenching mechanism was also clarified. Based on the temperature-dependent spectral survey, the thermally induced fluorescence quenching behavior of GSAG:Ce3+ (x = 1 at.%, y = 0.65) was measured, and the relevant activation energy was evaluated to 0.28 eV. Moreover, the effects of different Sc/Al substitution ratios on the thermal stability of GSAG:Ce3+ samples were also tested. Benefited from the tunable emission of GSAG:Ce3+ phosphors, the WLEDs device was fabricated by combining with a blue LED, yielding the Ra value of 82.1 and the CCT value of 3981 K. This study indicates the potential application of GSAG:Ce3+ phosphors in white lighting and also provides some guiding inspirations in the exploration of new garnet phosphors.