Full-spectrum Light Research Articles

Luminescence Spectroscopic Investigation of Eu<sup>3+</sup> Doped Oxides: Review

Given their potential utility in a variety of fields, including solid-state lighting, flat-panel displays, solar energy converters, optical amplifiers, and more, phosphors and glasses driven by Rare Earth (RE) ions and emitting multiple colors have attracted a lot of interest. Full-spectrum lighting, high-efficiency near-infrared emission, and wide colour gamut display are the primary difficulties for these emerging RE doped phosphors, which are dependent on the emission characteristics of the phosphors utilized. The various methods of synthesis for Eu3+ activated red emitting phosphors are discussed, with an emphasis on the aspects that contribute to improved luminous performance. This luminescence analysis is used in investing the Crystal structure and defects in metal oxides from which it provides information on the chemical and mechanical behavior of metal oxides during mining and processing operations. In this description, we outline the research findings and talk about the luminescence theory of the Eu3+ doped glasses and oxides for the red emission.

Tuning the selectivity of photothermal CO2 hydrogenation through photo-induced interaction between Ni nanoparticles and TiO2

Photothermal CO2 hydrogenation into value-added chemicals driven by abundant solar energy is a promising and sustainable approach for achieving carbon neutralization. Herein, we demonstrate the photo-induced interaction between Ni nanoparticles and TiO2 support (Ni@TiO2) for maneuvering the selectivity of photothermal CO2 hydrogenation. According to experimental characterizations and theoretical simulations, the formed strong metal-support interaction between Ni and TiO2 can significantly enhance the adsorption of key intermediate *CO for further hydrogenation, thus tuning the CO2 hydrogenation pathway toward CH4. Consequently, the Ni@TiO2 catalyst exhibits a CH4 production rate of 286.5 mmol gcat−1 h−1 with an 81.8% selectivity under full-spectrum solar light irradiation. Moreover, in situ experimental characterizations and theoretical calculations suggest that photothermal CO2 hydrogenation over Ni@TiO2 undergoes a stepwise hydrogenation pathway to methane. This work offers insights into a simple approach for designing efficient nonprecious metal-based CO2 methanation catalysts.

“One stone four birds” design atom co-sharing BiOBr/Bi2S3 S-scheme heterojunction photothermal synergistic enhanced full-spectrum photocatalytic activity

The rational design of heterostructure photocatalysts holds significant scientific and technical importance for maximizing the utilization of solar energy. In this study, a full spectrum-responsive S-scheme BiOBr/Bi2S3 heterojunction with co-sharing Bi atoms had been successfully constructed using an ion exchange approach accompanied by an in-situ growth process. Theoretical calculations and advanced techniques analysis demonstrate that the interfacial co-sharing of Bi atoms and the internal electric field (IEF) between BiOBr and Bi2S3 can greatly enhance S-scheme charge transfer, leading to effective spatial charge separation and the maintenance of maximum redox capacity. Additionally, the incorporation of Bi2S3 and the formation of oxygen vacancies (OVs) significantly increased NIR absorption and enhanced the photothermal property, further improving charge separation and utilization. As a result, the optimal photoreduction of Cr(VI) performance in BiOBr/Bi2S3 reached 100% within 10 min of full-spectrum light irradiation, and the CO yield was 20.32 µmol∙g–1 after 5 h of irradiation, which were 31.97 and 3.07 times higher than those of BiOBr, respectively. Furthermore, we elucidated the mechanism of Cr(VI) removal using DFT. This work provides valuable guidance for the rational design and construction of Bi-based S-scheme heterojunction photocatalysts with high-efficiency photocatalytic performance and effective solar light utilization.

Light exposure therapy for myopia control: a systematic review and Bayesian network meta-analysis

AimsTo compare and rank the myopia control effects of different light wavelengths in children using a systematic review and Bayesian network meta-analysis (Bayesian NMA).MethodsThe review protocol was registered with PROSPERO....

Bioinspired Asymmetric Polypyrrole Membranes with Enhanced Photothermal Conversion for Highly Efficient Solar Evaporation.

Solar-driven interfacial evaporation (SDIE) has attracted great attention by offering a zero-carbon-emission solution for clean water production. The manipulation of the surface structure of the evaporator markedly promotes the enhancement of light capture and the improvement of evaporation performance. Herein, inspired by seedless lotus pod, a flexible pristine polypyrrole (PPy) membrane with macro/micro-bubble and nanotube asymmetric structure is fabricated through template-assisted interfacial polymerization. The macro- and micro-hierarchical structure of the open bubbles enable multiple reflections inner and among the bubble cavities for enhanced light trapping and omnidirectional photothermal conversion. In addition, the multilevel structure (macro/micro/nano) of the asymmetric PPy (PPy-A) membrane induces water evaporation in the form of clusters, leading to a reduction of water evaporation enthalpy. The PPy-A membranes achieve a full-spectrum light absorption of 96.3% and high evaporation rate of 2.03kgm-2 h-1 under 1 sun. Long-term stable desalination is also verified with PPy-A membranes by applying one-way water channel. This study demonstrates the feasibility of pristine PPy membranes in SDIE applications, providing guidelines for modulation of the evaporator topologies toward high-efficient solar evaporation.

Biologically aware lighting for newborn intensive care.

We designed and implemented a novel neonatal intensive care (NICU) lighting system to support the current understanding of daylight-coupled physiology. We created a system that generates wavelengths corresponding to the known blue and violet activation spectra of non-visual opsins. These are known to mediate energy management and related physiologic activity. Light produced by the system spans the visible spectrum, including violet wavelengths that are blocked by modern glazing and not emitted by standard LED fixtures. System features include automated light and dark phases that mimic dawn/dusk. The system also matches length of day seasonality. Spectral composition can be varied to support translational research protocols. Implementation required a comprehensive strategy to inform bedside providers about the value and use of the lighting system. Full-spectrum lighting for the NICU is feasible and will inform the optimization of the NICU environment of care to support optimal neonatal growth and development.

Construction of IO-B-TiO2/In2O3 S-scheme heterojunction with photothermal effects and its highly efficient photocatalytic reduction of CO2 under full-spectrum light

The conversion of greenhouse gases such as carbon dioxide (CO2) into fuel and high-value chemical materials using solar energy is considered as a viable solution to the environmental pollution and the alleviation of the energy crisis. Herein, a black titanium dioxide/indium oxide S-scheme heterojunction (IO-B-TiO2/In2O3) with a three-dimensional porous inverse opal structure was prepared. In the photocatalytic reduction of CO2, IO-B-TiO2/In2O3 exhibited an excellent CO production rate (251.25 μmol·g−1·h−1), being 8.62 and 1.55 times of pure IO-TiO2 and IO-B-TiO2/In2O3 under non-photothermal conditions, respectively. A series of characterizations and theoretical calculations (DFT) systematically demonstrated that the excellent photocatalytic performance results from the full spectral response of the material, fast charge separation and transport efficiency, and superior photothermal conversion efficiency of the infrared light. This work will provide a promising insight to the design of S-scheme catalysts with outstanding photocatalytic performance via photothermal assistance and the improved solar energy conversion efficiency.

Comparative transcriptome analysis reveals growth and molecular pathway of body color regulation in turbot (Scophthalmus maximus) exposed to different light spectrum

Fish body color changes play vital roles in adapting to ecological light environment and influencing market value. However, the initial mechanisms governing the changes remain unknown. Here, we scrutinized the impact of light spectrum on turbot (Scophthalmus maximus) body coloration, exposing them to red, blue, and full light spectra from embryo to 90 days post hatch. Transcriptome and quantitative real-time PCR (qRT-PCR) analyses were employed to elucidate underlying biological processes. The results showed that red light induced dimorphism in turbot juvenile skin pigmentation: some exhibited black coloration (Red_Black_Surface, R_B_S), while others displayed lighter skin (Red_White_Bottom, R_W_B), with red light leading to reduced skin lightness (L*) and body weight, particularly in R_B_S group. Transcriptomic and qRT-PCR analyses showcased upregulated gene expressions related to melanin synthesis in R_B_S individuals, notably tyrosinase (tyr), tyrosinase-related protein 1 (tyrp1), and dopachrome tautomerase (dct), alongside solute carrier family 24 member 5 (slc24a5) and oculocutaneous albinism type II (oca2) as pivotal regulators. Nervous system emerged as a critical mediator in spectral environment-driven color regulation. N-methyl d-aspartate (NMDA) glutamate receptor, and calcium signaling pathway emerged as pivotal links intertwining spectral conditions, neural signal transduction, and color regulation. The individual differences in NMDA glutamate receptor expression and subsequent neural excitability seemed responsible for dichromatic body coloration in red light-expose juveniles. This study provides new insights into the comprehending of fish adaptation to environment and methods for fish body color regulation and could potentially help enhance the economic benefit of fish farming industry.

Pyrrole-Doped Polydopamine-Pyrrole (PDA-nPY) Nanoparticles with Tunable Size and Improved NIR Absorption for Photothermal Therapy.

Polydopamine (PDA) as a melanin-like biomimetic material with excellent biocompatibility, full spectrum light absorption capacity and antioxidation property has been extensively applied in the biomedical field. Based on the high reactivity of dopamine (DA), exploiting new strategies to fabricate novel PDA-based nano-biomaterials with controllable size and improved performance is valuable and desirable. Herein, we reported a facile way to synthesize pyrrole-doped polydopamine-pyrrole nanoparticles (PDA-nPY NPs) with tunable size and enhanced near-infrared (NIR) absorption capacity through self-oxidative polymerization of DA with PY in an alkaline ethanol/H2O/NH4OH solution. The PDA-nPY NPs maintain excellent biocompatibility and surface reactivity as PDA. By regulating the volume of added PY, PDA-150PY NPs with a smaller size (<100 nm) and four-fold higher absorption intensity at 808 nm than that of PDA can be successfully fabricated. In vitro and in vivo experiments effectively further demonstrate that PDA-150PY NPs can effectively inhibit tumor growth and completely thermally ablate a tumor. It is believed that these PY doped PDA-nPY NPs can be a potential photothermal (PT) agent in biomedical application.

Oyster shell-derived CuFe2O4-Hap nanocomposite for healthy houses: Bacterial and formaldehyde elimination

Bacterial infections and the threat of volatile organic compounds (VOCs) to human beings have attracted increasing concerns over the years. The simultaneous and effective eradication of bacteria while purifying indoor air has become an urgent issue. Herein, a biomass-based CuFe2O4-Hap was prepared via an ion-exchange method by loading CuFe2O4 with flower-shaped hydroxyapatite (Hap) obtained from oyster shells. Based on the experimental results and theoretical basis, the introduction of CuFe2O4 reduced the work function of hydroxyapatite and inhibited the recombination of photogenerated carriers. After irradiated for 15 min (300 W xenon lamp), the CuFe2O4-Hap photocatalysts exhibited excellent antibacterial efficiencies against Staphylococcus aureus (99.6 ± 0.35) % and Escherichia coli (99.7 ± 0.23) %, respectively. In addition, the functional coating prepared with CuFe2O4-Hap as the active material exhibited approximately 100 % HCHO conversion rate within 10 min under the full-spectrum light irradiation. The excellent photocatalytic decomposition performance could be attributed to the large specific surface area of nano-flower-shaped hydroxyapatite and the fast separation efficiency of photogenerated carriers. Overall, the proposed strategy is expected to stimulate further research into the biomass valorization for a healthier and environment-friendly lifestyle.

Preference of juvenile tiger puffer for light spectrum and tank colours based on different body size and breeding background

As important environmental factors, the light spectra and tank colours have not received sufficient attention. Most fishes have the ability to perceive environment, distinguish colours, and exhibit preferences or aversions towards different environments, which can provide a reference for the design of their rearing environment. Tiger puffer (Takifugu rubripes) is an important mariculture species in China and East Asia, but its preference for illumination spectra and tank colours is unclear. This study focuses on the preferences of juvenile tiger puffers for different spectra and tank background colours in different rearing backgrounds and body sizes. The experiments were conducted in a preference testing device, and the behavioural videos were recorded and analysed using a motion behaviour tracking system (EthoVision XT 12). The results show that the puffers showed preference for short-wavelength lights ((i.e., cyan, green, etc.), avoidance of long-wavelength light (i.e., red) and less stay time in the full light spectrum and dark. For tank colours, the puffers showed a preference for light background colours (i.e., white), and avoidance of deep background colours (i.e., dark, red, etc.). Fish body sizes and original breeding environment could significantly affect the selective preference of juvenile puffer (P < 0.05). Large puffers preferred green tank colour than small ones, while small ones preferred grey and red. The puffers reared in green light and grey tank for 3 months preferred green light spectrum and green tank colour compared with those reared in full spectrum and grey tank, while the fish reared in full spectrum preferred grey tank colour and area without light. It was also found that the movement rate of juvenile puffers was affected by the light spectra and tank colours and was positively correlated with light wavelength (P < 0.05). Therefore, for tiger puffer breeding, short-wavelength light spectrums (cyan, green, etc.) and light-coloured tank backgrounds (white) are recommended. Long-wavelength Light-emitting diodes and dark tank colours should be avoided in breeding. This study would provide a reference basis for fish light spectra and background colour preference studies, as well as for the improvement of breeding welfare and production efficiency of juvenile tiger puffer.

Multisite photocatalytic depolymerization of lignin model compound utilizing full-spectrum light over magnetic microspheres

Photocatalytic depolymerization is a high value-added approach for utilization of lignin. In this study, magnetic microspheres of FeCoRu@SiO2-TiO2 were synthesized by a co-precipitation method. Doping with CoOx and RuOx was used to improve the response to visible light, and doping with TiO2 was used to improve the response to ultraviolet light (λ<380nm). The lignin model compound depolymerization rate was >90%. The electron paramagnetic resonance results showed that the reaction occurred in two steps (aerobic phase and oxygen-free phase). Most of the O2- was produced in the first step by cleavage of C-O bonds. The second step was inhibited in an oxygen-free atmosphere. This research provides a valid method for enhancing the photocatalytic properties using full-spectrum light and exploring the lignin photocatalytic depolymerization mechanism. Further research is required to develop the catalyst properties and performance to produce radicals.

Tunable luminescence spectra of solid solution phosphors Gd3(Sb1-yTay)O7:Bi3+ for ultrahigh color rendering index full-spectrum white light-emitting diodes

The development of efficient luminescent materials that can compensate for the cyan gap is essential for actualizing high-quality full-spectrum white light-emitting diode (wLED) illumination. In this paper, a novel blue-emitting phosphor Gd3SbO7:Bi3+ was synthesized with an emission center located at 449 nm. Based on the cation substitution strategy, the cyan-emitting Gd3TaO7:Bi3+ phosphor is developed by completely replacing Sb5+ ions with Ta5+ ions in Gd3SbO7:Bi3+. Compared with Gd3SbO7:Bi3+, Gd3TaO7:Bi3+ also has an orthorhombic phase with the space group Ccmm, except that its emission wavelength is red-shifted by 45 nm from 449 to 494 nm, and the luminescence color is changed from blue to cyan. Thermal stability measurements demonstrate the negative effect of increasing Ta5+ doping concentration on the thermal stability of Gd3SbO7:Bi3+ phosphors. And a full-spectrum wLED device was fabricated using Gd3SbO7:Bi3+, Gd3TaO7:Bi3+, commercial (Sr, Ba)2SiO4:Eu2+ and CaAlSiN3:Eu2+ phosphors, with an impressive color rendering index (Ra = 94.7, R9 = 93) and suitable correlated color temperature (5832 K). The research results demonstrate the important role of Gd3TaO7:Bi3+ phosphors in compensating the cyan gap, and also provide new insights into the application of cyan phosphors in full-spectrum white light illumination.

Biochemical and molecular characterization of the SBiP1 chaperone from Symbiodinium microadriaticum CassKB8 and light parameters that modulate its phosphorylation.

The coding and promoter region sequences from the BiP-like protein SBiP1 from Symbiodinium microadriaticum CassKB8 were obtained by PCR, sequenced and compared with annotated sequences. The nucleotides corresponding to the full sequence were correctly annotated and the main SBiP1 features determined at the nucleotide and amino acid level. The translated protein was organized into the typical domains of the BiP/HSP70 family including a signal peptide, a substrate- and a nucleotide-binding domain, and an ER localization sequence. Conserved motifs included a highly conserved Thr513 phosphorylation site and two ADP-ribosylation sites from eukaryotic BiP's. Molecular modeling showed the corresponding domain regions and main exposed post-translational target sites in its three-dimensional structure, which also closely matched Homo sapiens BiP further indicating that it indeed corresponds to a BiP/HSP70 family protein. The gene promoter region showed at least eight light regulation-related sequences consistent with the molecule being highly phosphorylated in Thr under dark conditions and dephosphorylated upon light stimuli. We tested light parameter variations that could modulate the light mediated phosphorylation effect and found that SBiP1 Thr dephosphorylation was only significantly detected after 15-30 min light stimulation. Such light-induced dephosphorylation was observed even when dichlorophenyl dimethyl urea, a photosynthesis inhibitor, was also present in the cells during the light stimulation. Dephosphorylation occurred indistinctly under red, yellow, blue or the full visible light spectra. In additon, it was observed at a light intensity of as low as 1 μmole photon m-2 s-1. Our results indicate that: a) SBiP1 is a chaperone belonging to the BiP/HSP70 family proteins; b) its light-modulated phosphorylation/dephosphorylation most likely functions as an activity switch for the chaperone; c) this light-induced modulation occurs relatively slow but is highly sensitive to the full spectrum of visible light; and d) the light induced Thr dephosphorylation is independent of photosynthetic activity in these cells.

Efficient Blue–Violet Phosphor with Small Stokes‐Shift for Full‐Spectrum Lighting

AbstractBlue–violet phosphor is an essential component to realize full spectrum lighting on the basis of commercial 365 nm N‐UV chip excitation. However, its development falls behind since the phosphor with small stokes‐shift (ΔS) is hard to realize. Herein, a new blue–violet phosphor SrSc4Si5O17:Ce3+ with small ΔS (∼30 nm) is presented. SrSc4Si5O17:Ce3+ emits bright blue–violet luminescence peaking at 390 nm, and the internal/external quantum efficiency can reach 73.4%/50.4% under 365 nm excitation. The unique luminescence performance of the phosphor is related closely to its crystal structure. The host‐referred bind energy (HRBE) diagram is also successfully constructed to illustrate its thermal quenching behavior. Finally, the packaged white light‐emitting diodes based on the 365 nm N‐UV chip, SrSc4Si5O17:Ce3+, and other high‐performance phosphors have an ultra‐high color rendering index (Ra = 95.9), indicating that SrSc4Si5O17:Ce3+ is a potential candidate for various applications, including indoor healthy lighting and agricultural lighting.

The Synergistic Effect of Full-Spectrum Light Therapy and Transient Immunosuppressants Prolonged Allotransplant Survival.

The lifelong administration of immunosuppressants remains the largest drawback in vascularized composite allotransplantation (VCA). Therefore, developing alternative strategies to minimize the long-term use of immunosuppressive agents is crucial. This study investigated whether full-spectrum bright light therapy (FBLT) combined with short-term immunosuppressant therapy could prolong VCA survival in a rodent hindlimb model. Hindlimb allotransplantation was conducted from Brown-Norway to Lewis rats, and the rats were divided into 4 groups. Group 1 did not receive treatment as a rejection control. Group 2 received FBLT alone. Group 3 was treated with short-term antilymphocyte serum (ALS) and cyclosporine A (CsA). Group 4 was administered short-term ALS/CsA combined with FBLT for 8 weeks. Peripheral blood and transplanted tissues were collected for analysis. The results revealed median survival time of FBLT alone (group 2) did not increase allograft survival compared with the control (group 1). However, in group 4, FBLT combined with short-term ALS/CsA, median composite tissue allograft survival time (266 days) was significantly prolonged compared with groups 1 (11 days), 2 (10 days), and 3 (41 days) ( P < 0.01). Group 4 also showed a significant increase in regulatory T cells ( P = 0.04) and transforming growth factor-β1 levels ( P = 0.02), and a trend toward a decrease in interleukin-1β levels ( P = 0.03) at 16 weeks after transplantation as compared with control (group 1). FBLT combined with short-term immunosuppressants prolonged allotransplant survival by modulating T-cell regulatory functions and antiinflammatory cytokine expression. This approach could be a potential strategy to increase VCA survival. Full-spectrum light therapy could be a potential strategy to increase vascularized composite allotransplant survival.

Phase behavior and GOR evolution using a natural maturity series of lacustrine oil-prone shale: Implications from compositional modelling

For the exploration of shale oil, there is still an urgent need to relate hydrocarbon generation reactions and changing phase behavior to exact levels of thermal maturity. Six organic-rich shale samples from the Cretaceous Qingshankou Formation, Songliao Basin spanning the maturity range with vitrinite reflectance (Ro) 0.58%–1.16% were studied for petroleum generation characteristics using the PhaseKinetics, PhaseSnapshot, and GORFit approaches. All samples show very good petroleum potential and contain Type I kerogen with total organic carbon contents ranging between 1.5% and 5%. A full spectrum of light to heavy hydrocarbons, consistent with live oils, occurs in thermal extracts of all samples. Gas chromatography fingerprints of samples with Ro > 0.7% closely resemble waxy oils derived from lacustrine organic matter (OM); fingerprints of lower maturity samples are not yet as wax rich. The inferred petroleum type organofacies of all samples is paraffinic high wax with low organic sulfur levels. Hydrocarbon generation from the least mature sample is characterized by one dominant activation energy at 55 kcal/mol, accounting for 87% of the total bulk reaction. Assuming a simplified geological scenario, i.e., a 3 K/My linear heating rate, primary petroleum is generated (transformation ratio, i.e., TR: 10%–90%) over a narrow temperature interval of only 23 °C. Onset (10% TR), maximum (Tpeak), and completion (90% TR) temperatures and Ro values are 141 °C at Ro 0.85%, 155 °C at Ro 1.08%, and 164 °C at Ro 1.2%, respectively. Primary gas generation (148–172 °C) occurs 10 °C later (300 m deeper) than the generation of C6+ compounds (138–161 °C). Secondary gas formation from oil cracking begins at 182 °C, maximizes at 197 °C, and is completed well before 225 °C (beginning of late gas generation from the secondary cracking of thermally matured, macromolecular organic matter) at 206 °C. Thus, primary and secondary oil cracking processes do not overlap under geological conditions. In line with a paraffinic high-wax oil petroleum type organofacies, cumulative fluids generated from the least mature sample fall within the black oil class over most of the primary kerogen conversion range up to 90% TR as indicated by low saturation pressures (Psat) and gas-oil-ratios generally below 160 Sm3/Sm3. Maturation results in relatively heavy fluids with Psat values in the range 40–70 bar when the free hydrocarbons, i.e., already present prior to pyrolysis, are included, and in lighter fluids with Psat values in the range 70–90 bar, when the free, mostly waxy hydrocarbons, are excluded. Systematics of physical properties and fluid compositions evolution reproduce the general behavior of naturally occurring petroleum sourced from lacustrine OM very well and fit physical properties and compositions of produced shale oils in the Songliao Basin at comparable maturity levels.

GAS SENSOR BASED ON THE SPECTRAL SPR EFFECT WITH COLORIMETRIC REGISTRATION OF RESPONSES

A new variant of the optoelectronic sensor for the detection of gas molecules based on the effect of spectral surface plasmon resonance (SPR) in the chromatic mode with colorimetric registration of the color components of the reflected light is proposed. As an optical sensitive element, a thin silver film was used on the base face of the prism in the Kretschmann geometry, which made it possible to realize a full-fledged SPR effect in the entire visible spectral range from 450 to 700 nm. To measure the optical response, the method of video registration of R, G, B components of reflected light by color webcam was used. The optical scheme of the set-up allowed to simultaneously obtain the full spectrum of plasmon-reflected light without the use of rotating mechanical parts. The sensory effect was a change in the refractive index of the surrounding medium under the action of gases, which directly affected the parameters of the spectral SPR. A laboratory prototype of an optoelectronic sensor device was created, and the effectiveness of the proposed method was evaluated by detection of a number of organic analytes vapors .

Tandem CQDs loaded triple metal oxide interface-reinforced built-in electric field for a wide-spectral-responsive photocatalyst

Focusing at efficient Cefixime (CEFX) removal, a delicate ultrathin-Bi2WO6 (UBWO) stacked quasi-CoFe2O4 binanosheets (BT) were meticulously designed and integrated with spherical MnWO4 (MWO) and carbon quantum dots (CQDs), forming a n-p-n CQDs@MWO/CFO:UBWO nanohybrid. XRD, XPS, TEM and other systematic analysis demonstrated the vertically aligned layer by layer assembly of UBWO:CFO BT, and a shift in the highly exposed (211) facet of UBWO after nanohybrid formation as well as large surface area (323.33 m2/g) was achieved. UV–vis DRS, PL and EIS proved high separation efficiency, prolonged life time and photogeneration of more charge carriers with absorption of full light spectrum. As expected, the optimized 5 %CQDs@0.25MWO/0.1CFO:UBWO nanohybrid displayed excellent visible light absorption and outstanding CEFX photodegradation whose kinetic constant were 21.11, 12.5, 8.82 folds higher than UBWO, CFO and MWO counterparts. This enhanced photodegradation performance ascribed to the dual strategy as follows: (i) Cascaded charge transfer with the Built-in electric field (BIEF) after n-p-n heterojunction, (ii) the upconverted PL and the electron reservoir properties of CQDs. Degradation efficiency maintained over six consecutive cycles affirming the superior recyclability of the photocatalyst. A possible degradation pathway was proposed based on GC-MS/MS analysis and the end products toxicity were systematically predicted using ECOSAR program. The toxicity of the end product was investigated against bacterial species. The proposed work provides a novel way for the fabrication of efficient photocatalyst with excellent practical applicability.

High-color-quality blue-light-pumped full-spectrum white-light-emitting diodes realized by efficient green-emitting CaY2HfScAl3O12:Ce3+ phosphors

Rare-earth doped inorganic phosphors are critical for solid-state white lighting. Particularly, efficient broadband, blue-light-excitable, green-emitting phosphors are highly needed for fabricating full-spectrum white-light-emitting diodes (WLEDs) with high-color-quality. Herein, we describe a new efficient blue-light-excited CaY2HfScAl3O12:Ce3+ green phosphor with high quantum efficiency (QE) and broad emission bandwidth. X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectrometer, excitation and emission spectra, CIE color coordinates, QE values, and temperature-dependent emission spectra have been used to characterize the samples. Rietveld refinement reveals that the CaY2HfScAl3O12 garnet compound has a cubic structure with lattice parameters of a = b = c = 12.38(13) Å, α = β = γ = 90°, and V = 1897.85(6) Å3. Impressively, the Ce3+ ions in the CaY2HfScAl3O12 host exhibit broadband excitation bands in the 300–500 nm spectral range with a maximum at 450 nm. Upon 450 nm excitation, the optimal phosphor doped with 2 mol% Ce3+ shows a broad green emission band in the wavelength range of 460–750 nm peaking around 532 nm, along with full width at half maximum of 121 nm as well as high internal QE of 78.9% and external QE of 46.6%. Ce3+ concentration-dependent luminescence properties and thermal stability at elevated temperature have been comprehensively studied. Finally, a WLED device is fabricated by utilizing CaY2HfScAl3O12:Ce3+ green phosphor, CaAlSiN3:Eu2+ red phosphor and a 450 nm blue LED chip, which generates bright full-spectrum warm-white light with ultrahigh color rendering index (Ra = 98.0, R9 = 97.5) and low correlated color temperature of 3602 K under 180 mA drive current. This work provides new insights into designing and developing efficient green phosphors for full-spectrum LED lighting.