High-Performance Photocatalytic Oxidation Reactor System

Airborne volatile organic chemicals are oxidized using blue LEDs, fiber optics, and visible light-activated catalysts for space and terrestrial air purification.

As crewed space missions extend beyond low Earth orbit, the need to reliably recover potable water is critical. Aboard the International Space Station (ISS), the water is recycled from cabin humidity condensate, urine distillate, and hygiene wash wastes. In spacecraft cabin air environments, off-gassing from equipment, human metabolism, and human personal care products contributes to significant airborne concentrations of volatile organic compounds (VOCs). These polar and water-soluble compounds ultimately dissolve into the humidity condensate and stress the process load, logistics costs, and lifecycle requirements of the water processing systems. The aim of this effort was to develop the High Performance Photocatalytic Oxidation Reactor System (HPPORS) technology for the destruction of airborne VOCs prior to reaching the water processing systems. This innovation will reduce the logistics costs and lifecycle requirements of water processing systems, and help extend NASA missions to include long-duration space habitation and lunar and Mars colonization missions.

Posted in: Briefs, Aerospace, Green Design & Manufacturing, Recycling Technologies, Remediation Technologies, LEDs, Lighting, Materials, Fiber Optics, Photonics, Light emitting diodes (LEDs), Light emitting diodes (LEDs), Catalysts, Volatile organic compounds

Quantum Dots Improve Colors on TV and Computer Screens

Sandwiching QDs between two polymer films for protection is the key to success.

High-tech specks called quantum dots could bring brighter, more vibrant color to mass market TVs, tablets, phones and other displays. A new technology called 3M quantum dot enhancement film (QDEF), unveiled at the 248th National Meeting & Exposition of the American Chemical Society (ACS), has the potential to efficiently make liquid crystal display (LCD) screens more richly colored. That’s because quantum dot, or “QD,” displays need less energy compared to other high-color options. QDs are superconducting crystals so small that 10,000 could fit across the width of a human hair.

Posted in: Briefs, Lighting, OLEDs, Semiconductor devices, Semiconductor devices, Displays, Displays, Product development

Scientists Create Semiconductor Junction Only Three Atoms Thick

New technique could someday produce in-plane quantum wells and quantum wires, superlattices, and fully functioning transistors.

Scientists at the University of Washington have developed what they believe is the thinnest-possible semiconductor, a new class of nanoscale materials made in sheets only three atoms thick. Two of these single-layer semiconductor materials can be connected in an atomically seamless fashion known as a heterojunction. A heterojunction is the interface that occurs between two layers or regions of dissimilar crystalline semiconductors, both of which have unequal band gaps. This result could be the basis for next-generation flexible and transparent computing, better light-emitting diodes (LEDs), and solar technologies.

Posted in: Briefs, Lighting, Downsizing, Product development, Semiconductors

Gallium Nitride Nanowire Tips Function as LEDs

Probe tips for atomic force microscope can be used to illuminate tiny sample region with optical radiation.

A team of researchers has demonstrated that atomic force microscope (AFM) probe tips made from its near-perfect gallium nitride nanowires are superior in many respects to standard silicon or platinum tips in measurements of critical importance to microchip fabrication, nanobiotechnology, and other endeavors. In addition, the scientists have invented a means of simultaneously using the nanowire tips as LEDs to illuminate a tiny sample region with optical radiation while it is scanning, adding an entirely new dimension to the characterization of nanoelectronics materials and devices.

Posted in: Briefs, Lighting

New Technique Makes LEDs Brighter, More Resilient

Coating polar gallium nitride (GaN) with a layer of phosphorous-derived acid increases luminescence without increasing energy input.

Researchers from North Carolina State University have developed a new processing technique that makes light emitting diodes (LEDs) brighter and more resilient by coating the semiconductor material gallium nitride (GaN) with a layer of phosphorus-derived acid.

Posted in: Briefs, Lighting

First Single-Molecule LED Developed

Breakthrough could be the first step towards making molecule-sized components that combine electrical and optical properties.

The ultimate challenge in the race to miniaturize light emitting diodes (LED) has finally been met. A team led by the Institut de Physique et de Chimie des Matériaux de Strasbourg (IPCMS, CNRS/Université de Strasbourg), in collaboration with UPMC and CEA, has developed the first-ever single-molecule LED.

Posted in: Briefs, Lighting, Downsizing, Light emitting diodes (LEDs), Light emitting diodes (LEDs), Product development

Two-Dimensional Material Shows Promise for Optoelectronics

Team creates LEDs, photovoltaic cells, and light detectors using novel one-molecule-thick material.

A team of MIT researchers has used a novel material that’s just a few atoms thick to create devices that can harness or emit light. This proof-of-concept could lead to ultra-thin, lightweight, and flexible photovoltaic cells, light emitting diodes (LEDs), and other optoelectronic devices.

Posted in: Briefs, Lighting, Downsizing, Optics, Optics, Research and development, Materials properties

Improving the Efficiency of Green-Blue-Ultraviolet Light-Emitting Diodes

New approach could lead to the creation of low threshold lasers and high power light emitting diodes (LEDs).

Scientists at the U.S. Naval Research Laboratory (NRL) have suggested a method that could significantly increase the efficiency of green-blue-ultraviolet light-emitting diodes based on GaInN/GaN, AlGaN/GaN, and AlInN/GaN quantum wells. Their approach could enable advances in solid state lighting and the creation of low threshold lasers and high power light emitting diodes (LEDs).

Posted in: Briefs, Lighting, Light emitting diodes (LEDs), Light emitting diodes (LEDs), Research and development

New Approach To Growing InGaN Crystals For Diodes Could Also Improve Solar Cell Efficiency

Metal-modulated epitaxy allows an atomic, layer-by-layer growth of the material.

Crystals form the basis for the penetrating icy blue glare of car headlights and now they could be fundamental to the future in solar energy technology? Crystals are at the heart of diodes. Not the kind you might find in quartz, formed naturally, but manufactured to form alloys, such as indium gallium nitride or InGaN. This alloy forms the light emitting region of LEDs, for illumination in the visible range, and of laser diodes (LDs), in the blue-UV range.

Posted in: Briefs, Lighting

New Plastic-Like Polymer Could Lead To White Organic LEDs

Inserting platinum metal atoms into a chain-like organic polymer enabled tuning of the colors emitted.

By inserting platinum atoms into an organic semiconductor, University of Utah physicists were able to “tune” the plastic-like polymer to emit light of different colors – a step toward more efficient, less expensive and truly white organic LEDs for light bulbs of the future.

Posted in: Briefs, Lighting

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