Studies on Optical Consistency of White LEDs Affected by Phosphor Thickness and Concentration Using Optical Simulation

AbstractIn this work, strongly blue emitting Ce3+-activated BaAl2O4 nanophosphors were successfully synthesized by a sol–gel technique. The crystal structure, morphology, and microstructure of the nanophosphors have been studied by X-ray powder diffraction, field emission scanning electron microscopy, and high-resolution transmission electron microscopy. The photoluminescence spectra show the impact of concentration variation of Ce3+ on the photoluminescence emission of the phosphor. These nanophosphors display intense blue emission peaking at 422 nm generated by the Ce3+ 5d → 4f transition under 350 nm excitation. Our results reveal that this nanophosphor has the capability to take part in the emergent domain of solid-state lighting and field-emission display devices.

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Synthesis, photoluminescence and Li+ concentration effect on new reddish phosphor Li2Sr2Al(PO4)3:Sm3+ for white LEDs

Inorganic Chemistry Communications ◽

10.1016/j.inoche.2020.108152 ◽

2020 ◽

Vol 120 ◽

pp. 108152 ◽

Cited By ~ 1

Author(s):

Haidong Ju ◽

Yongbo Liu ◽

Xianlin Huang ◽

Xiangqiao Feng ◽

Baoling Wang ◽

...

Keyword(s):

Concentration Effect ◽

White Leds

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Imaging terrestrial planets with a free-flying occulter and space telescope: an optical simulation

10.1117/12.506192 ◽

2003 ◽

Author(s):

Alfred B. Schultz ◽

Richard G. Lyon ◽

Mark Kochte ◽

Dorothy A. Fraquelli ◽

Frederick Bruhweiler ◽

...

Keyword(s):

Optical Simulation ◽

Terrestrial Planets ◽

Space Telescope

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LED Lighting and High-Density Planting Enhance the Cost-Efficiency of Halimione portulacoides Extraction Units for Integrated Aquaculture

Applied Sciences ◽

10.3390/app11114995 ◽

2021 ◽

Vol 11 (11) ◽

pp. 4995

Author(s):

Marco Custódio ◽

Paulo Cartaxana ◽

Sebastián Villasante ◽

Ricardo Calado ◽

Ana Isabel Lillebø

Keyword(s):

Plant Density ◽

Inorganic Nitrogen ◽

High Density ◽

Planting Density ◽

Nitrogen And Phosphorus ◽

Integrated Aquaculture ◽

Halimione Portulacoides ◽

White Leds ◽

Artificial Lighting ◽

Aquaculture Effluents

Halophytes are salt-tolerant plants that can be used to extract dissolved inorganic nutrients from saline aquaculture effluents under a production framework commonly known as Integrated Multi-Trophic Aquaculture (IMTA). Halimione portulacoides (L.) Aellen (common name: sea purslane) is an edible saltmarsh halophyte traditionally consumed by humans living near coastal wetlands and is considered a promising extractive species for IMTA. To better understand its potential for IMTA applications, the present study investigates how artificial lighting and plant density affect its productivity and capacity to extract nitrogen and phosphorous in hydroponic conditions that mimic aquaculture effluents. Plant growth was unaffected by the type of artificial lighting employed—white fluorescent lights vs. blue-white LEDs—but LED systems were more energy-efficient, with a 17% reduction in light energy costs. Considering planting density, high-density units of 220 plants m−2 produced more biomass per unit of area (54.0–56.6 g m−2 day−1) than did low-density units (110 plants m−2; 34.4–37.1 g m−2 day−1) and extracted more dissolved inorganic nitrogen and phosphorus. Overall, H. portulacoides can be easily cultivated hydroponically using nutrient-rich saline effluents, where LEDs can be employed as an alternative to fluorescent lighting and high-density planting can promote higher yields and extraction efficiencies.

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Microwave-Assisted Preparation of Luminescent Inorganic Materials: A Fast Route to Light Conversion and Storage Phosphors

Molecules ◽

10.3390/molecules26102882 ◽

2021 ◽

Vol 26 (10) ◽

pp. 2882

Author(s):

José Miranda de Carvalho ◽

Cássio Cardoso Santos Pedroso ◽

Matheus Salgado de Nichile Saula ◽

Maria Claudia França Cunha Felinto ◽

Hermi Felinto de Brito

Keyword(s):

Rapid Heating ◽

Inorganic Materials ◽

Rapid Screening ◽

Conventional Heating ◽

Quantum Yields ◽

Microwave Assisted Synthesis ◽

Volumetric Heating ◽

White Leds ◽

Microwave Assisted ◽

And Storage

Luminescent inorganic materials are used in several technological applications such as light-emitting displays, white LEDs for illumination, bioimaging, and photodynamic therapy. Usually, inorganic phosphors (e.g., complex oxides, silicates) need high temperatures and, in some cases, specific atmospheres to be formed or to obtain a homogeneous composition. Low ionic diffusion and high melting points of the precursors lead to long processing times in these solid-state syntheses with a cost in energy consumption when conventional heating methods are applied. Microwave-assisted synthesis relies on selective, volumetric heating attributed to the electromagnetic radiation interaction with the matter. The microwave heating allows for rapid heating rates and small temperature gradients yielding homogeneous, well-formed materials swiftly. Luminescent inorganic materials can benefit significantly from the microwave-assisted synthesis for high homogeneity, diverse morphology, and rapid screening of different compositions. The rapid screening allows for fast material investigation, whereas the benefits of enhanced homogeneity include improvement in the optical properties such as quantum yields and storage capacity.

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Utilizing energy transfer strategy to produce efficient green luminescence in Ca2LuHf2Al3O12:Ce3+,Tb3+ garnet phosphors for high-quality near-UV-pumped warm-white LEDs

Journal of Colloid and Interface Science ◽

10.1016/j.jcis.2021.05.108 ◽

2021 ◽

Author(s):

Nan Ma ◽

Wei Li ◽

Balaji Devakumar ◽

Zongjie Zhang ◽

Xiaoyong Huang

Keyword(s):

Energy Transfer ◽

Green Luminescence ◽

High Quality ◽

White Leds

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