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Particle Physics Outreach to Secondary Education

This review summarizes exemplary secondary education and outreach programs of the particle physics community. We examine programs from the following areas: research experiences, high-energy physics data for students, informal learning for students, instructional resources, and professional development. We report findings about these programs' impact on students and teachers and provide suggestions for practices that create effective programs from those findings. We also include some methods for assessing programs.

43 PARTICLE ACCELERATORS↗

High Performance Computing Cluster Engineering Academy

Collection of tools and code for evaluation testing of HPC orchestration solutions by HPCCEA summer students. These scripts and configuration files were written by HPCCEA summer students as part of their summer internship where they explore alternative solutions to our current HPC cluster management software. These scripts/configuration files range from using configuration management tools (Puppet, Chef, Ansible, Fabric, etc.) to scripting languages (Phython, BASH, Perl, etc.). Each year, new students will be added to the project and expand on previous years work.

Bennett, ThomasG↗

Analyzing School Bus Electrification in Richmond, Virginia

School buses are an essential component of the transportation infrastructure, serving as a lifeline for students across the globe. However, the widespread use of diesel school buses has raised concerns about the health impact on millions of students exposed to harmful emissions daily. Recognizing this issue, school districts worldwide are urgently seeking cleaner energy alternatives. Electric school buses emerge as an environmentally friendly and sustainable option, fostering a healthier environment for both students and communities. However, school bus electrification faces the challenges of high upfront cost, cumbersome charging management, and constraints from power grids. To help school bus operators address those challenges, this study presents a data-driven analysis for school bus electrification. This study considered a real-world school bus system in Richmond, VA, and developed a mathematical programming model to analyze the system design, charging strategies, and charging load profiles for the electrification scenario. The study evaluated different charging strategies based on model outcomes, aiming to optimize efficiency and effectiveness. Ultimately, this research generated electric school bus charging demand profiles under various scenarios, shedding light on the feasibility and implications of transitioning to electric-powered school buses.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

2020 ETI Annual Summer School: Data Science and Engineering

The Consortium for Enabling Technologies & Innovation (ETI) was established in 2019 to address emerging technologies within the context of nuclear nonproliferation. ETI creates a research and education environment to support cross-cutting technologies across three core disciplines: 1) computer and engineering science research specifically in a form of machine learning and high performance computing (HPC), 2) advanced manufacturing, and 3) nuclear detection technologies. For outreach and development, ETI hosted the first of three summer schools from August 24-28, 2020 with the theme of “Data Science and Engineering”. The school was hosted in an on-line format and had over 200 participants. The recorded content is available on-line as a resource for students. The summer school had four modules: 1) Fundamentals of data Applications, 2) Computational Machine Learning, 3) Bayesian Modeling and Inference, and 4) Data Science for Safeguards. Modules contained both lectures as well as student exercises. Poll Everywhere was utilized in some modules as an on-line method to engage large groups of students. Upcoming ETI Summer Schools include Novel Instrumentation in 2021 and Advanced Manufacturing in 2022.

Biegalski, Steven R.↗

Board 160: Empowerment in STEM Day: Introducing High School Girls to Careers at National Laboratories (Work in Progress)

In the US, women are still vastly underrepresented in STEM (science, technology, engineering, and mathematics) careers, and various studies have shown that girls' interest in STEM careers wane as high school progresses. With this challenge in mind, Empowerment in STEM Day was organized by Lawrence Berkeley National Laboratory (LBNL), hosting 47 high school students from 6 public high schools in the area. This one-day event was designed and executed through a collaboration between the Women's Support and Empowerment Council (WSEC) and the K-12 STEM Education and Outreach Program at LBNL. The main goal of this program was to provide high school girls, who have little access to STEM career role-models in their immediate surroundings with insights into how a career in STEM looks like. Invitations to participate in the program were sent out to six local high schools in the Bay area asking educators to identify female students that were interested in STEM. Each high school participant was provided with an opportunity to experience a national laboratory environment, learn more about summer workshops and paid summer research internship opportunities at LBNL for high school students, and engage directly with LBNL's employees through job shadow, career mapping and speed networking sessions. In this paper, we will present an overview of the event organization, challenges faced during planning and execution of the event, discuss the lessons learned from the first Empowerment in STEM Day and suggest strategies for incorporating such events at other national laboratories and academic institutions as part of a vital effort into recruiting and retaining more high school girls in STEM-based careers. Additionally, since this was the first in-person event hosted by LBNL's K-12 Program after the pandemic, we will also share the strategies implemented at the event so as to engage both remote and on-site employees as volunteers.

Bose, Baishakhi↗

MIT Clean Energy Prize: Final Technical Report May 12, 2010 - May 11, 2011

The MIT Clean Energy Prize (MIT CEP) is a venture creation and innovation competition to encourage innovation in the energy space, specifically with regard to clean energy. The Competition invited student teams from any US university to submit student-led ventures that demonstrate a high potential of successfully making clean energy more affordable, with a positive impact on the environment. By focusing on student ventures, the MIT CEP aims to educate the next generation of clean energy entrepreneurs. Teams receive valuable mentoring and hard deadlines that complement the cash prize to accelerate development of ventures. The competition is a year-long educational process that culminates in the selection of five category finalists and a Grand Prize winner and the distribution of cash prizes to each of those teams. Each entry was submitted in one of five clean energy categories: Renewables, Clean Non-Renewables, Energy Efficiency, Transportation, and Deployment.

Snyder, Chris↗

Scaling of Microcavity Plasmas Toward 1 µm. Science and Engineering of Spatially-Confined, Low Temperature Plasmas

The DOE has provided, by means of the American Recovery and Reinvestment Act (ARRA), $146,400 in funding for the purchase of scientific equipment. Specifically, these funds have enabled the purchase of two scientific cameras that have already been applied to the research in microcavity plasmas at the University of Illinois (Urbana). The first camera system that was purchased with these funds is a gated ICCD system that allows events as short as 5 ns in time to be captured. It is difficult to express the impact that this equipment has already had on our research. Despite having arrived just 6 - 7 months ago, this camera system has already been used by five graduate students and several undergraduates to capture phenomena that we simply could not see in the past. As an example, the low temperature plasma confined to a spiral structure we fabricate in the Al/Al₂O₃ materials system appears, on long time scales such as those we see with our eyes, to be spatially uniform. However, when captured with the new camera system, the plasma actually is formed initially at the center of the spiral and then moves radially (literally, "jumping" over channels as it goes) at a velocity of a few km/sec. This is an exciting result and I should add that the camera shows that plasma standing waves are produced in some of the structures as well. We do not currently understand all of the phenomena we are witnessing but it is obvious that this new system has quite literally opened new areas of plasma research and application. The second system purchased under this ARRA grant is an infrared system that is far more sensitive than anything our laboratory (or the University of Illinois, for that matter) has had previously. Although fewer experiments have been completed to date with this second camera, it is already clear that it is, indeed, extremely sensitive and it is slated for several experiments in the near future in which we will be measuring the infrared spectra of several arrays of microcavity plasmas. In summary, let me express my thanks to the DOE for granting these funds. We are most grateful for the extraordinary scientific capability that thee funds provide our students. We expect that the scientific data already acquired by this equipment will result in several publications in the next 2 - 3 months (two are being written now). Furthermore, the ability we now have to watch plasmas evolve on the nanosecond time scale has given us several ideas that are likely to result in patent applications. On behalf of our students and myself, I thank the DOE for this exceptional equipment.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗

Messiah College Biodiesel Fuel Generation Project (Final Technical Report)

Many obvious and significant concerns arise when considering the concept of small-scale biodiesel production. Does the fuel produced meet the stringent requirements set by the commercial biodiesel industry? Is the process safe? How are small-scale producers collecting and transporting waste vegetable oil? How is waste from the biodiesel production process handled by small-scale producers? These concerns and many others were the focus of the research preformed in the Messiah College Biodiesel Fuel Generation project over the last three years. This project was a unique research program in which undergraduate engineering students at Messiah College set out to research the feasibility of small-biodiesel production for application on a campus of approximately 3000 students. This Department of Energy (DOE) funded research program developed out of almost a decade of small-scale biodiesel research and development work performed by students at Messiah College. Over the course of the last three years the research team focused on four key areas related to small-scale biodiesel production: Quality Testing and Assurance, Process and Processor Research, Process and Processor Development, and Community Education. The objectives for the Messiah College Biodiesel Fuel Generation Project included the following: 1. Preparing a laboratory facility for the development and optimization of processors and processes, ASTM quality assurance, and performance testing of biodiesel fuels. 2. Developing scalable processor and process designs suitable for ASTM certifiable small-scale biodiesel production, with the goals of cost reduction and increased quality. 3. Conduct research into biodiesel process improvement and cost optimization using various biodiesel feedstocks and production ingredients.

09 BIOMASS FUELS↗

Solid Oxide Fuel Cell Systems PVL Line

In July 2010, Stark State College (SSC), received Grant DE-EE0003229 from the U.S. Department of Energy (DOE), Golden Field Office, for the development of the electrical and control systems, and mechanical commissioning of a unique 20kW scale high-pressure, high temperature, natural gas fueled Stack Block Test System (SBTS). SSC worked closely with subcontractor, Rolls-Royce Fuel Cell Systems (US) Inc. (RRFCS) over a 13 month period to successfully complete the project activities. This system will be utilized by RRFCS for pre-commercial technology development and training of SSC student interns. In the longer term, when RRFCS is producing commercial products, SSC will utilize the equipment for workforce training. In addition to DOE Hydrogen, Fuel Cells, and Infrastructure Technologies program funding, RRFCS internal funds, funds from the state of Ohio, and funding from the DOE Solid State Energy Conversion Alliance (SECA) program have been utilized to design, develop and commission this equipment. Construction of the SBTS (mechanical components) was performed under a Grant from the State of Ohio through Ohio's Third Frontier program (Grant TECH 08-053). This Ohio program supported development of a system that uses natural gas as a fuel. Funding was provided under the Department of Energy (DOE) Solid-state Energy Conversion Alliance (SECA) program for modifications required to test on coal synthesis gas. The subject DOE program provided funding for the electrical build, control system development and mechanical commissioning. Performance testing, which includes electrical commissioning, was subsequently performed under the DOE SECA program. Rolls-Royce Fuel Cell Systems is developing a megawatt-scale solid oxide fuel cell (SOFC) stationary power generation system. This system, based on RRFCS proprietary technology, is fueled with natural gas, and operates at elevated pressure. A critical success factor for development of the full scale system is the capability to test fuel cell components at a scale and under conditions that can be accurately extrapolated to full system performance. This requires specially designed equipment that replicates the pressure (up to 6.5 bara), temperature (about 910 C), anode and cathode gas compositions, flows and power generation density of the full scale design. The SBTS fuel cell anode gas is produced through the reaction of pipeline natural gas with a mixture of steam, CO2, and O2 in a catalytic partial oxidation (CPOX) reactor. Production of the fuel cell anode gas in this manner provides the capability to test a fuel cell with varying anode gas compositions ranging from traditional reformed natural gas to a coal-syngas surrogate fuel. Stark State College and RRFCS have a history of collaboration. This is based upon SSCAs commitment to provide students with skills for advanced energy industries, and RRFCS need for a workforce that is skilled in high temperature fuel cell development and testing. A key to this approach is the access of students to unique SOFC test and evaluation equipment. This equipment is designed and developed by RRFCS, with the participation of SSC interns. In the near-term, the equipment will be used by RRFCS for technology development. When this stage is completed, and RRFCS has moved to commercial products, SSC will utilize this equipment for workforce training. The RRFCS fuel cell design is based upon a unique ceramic substrate architecture in which a porous, flat substrate (tube) provides the support structure for a network of solid oxide fuel cells that are electrically connected in series. These tubes are grouped into a {approx}350-tube repeat configuration, called a stack/block. Stack/block testing, performed at system conditions, provides data that can be confidently scaled to full scale performance. This is the basis for the specially designed and developed test equipment that is required for advancing and accelerating the RRFCS SOFC power system development program. All contract DE-EE0003229 objectives were achieved and deliverables completed during the period from March 1, 2010 through March 31, 2011. As a result of program completion, the Stack Block Test System was ready to support installation and electrical operation of a RRFCS solid oxide fuel cell (SOFC) stack block in the second quarter of 2011.

01 COAL, LIGNITE, AND PEAT↗

2011 World Materials Summit: Panel Discussion Report

The 2011 World Materials Summit, held on 10/9-12/2011 in Washington DC, provided a forum for top decision makers and energy experts from aropund the world to focus on the materials research needs for the growing energy economy. Organized jointly by the Materials Research Society (MRS), the European MRS (E-MRS), and the Chinese MRS (C-MRS), the goal of the Summit was to explore how the different regions of the world can work together on the critical issue of clean energy, including its relation to environmental sustainability and water. The participants considered the area of materials research as well as advocacy, economics, outreach, and education. Realizing that the concerns are long-term and that young players will ultimately be the ones who are going to need to solve the energy challenges, the chairs of the Summit inaugurated a Student Congress, a program for graduate students and postdoctoral scholars in fields directly related to energy and environmental science, engineering, and/or policy. The top 45 candidates coming from 18 countries were selected on a competititve basis to participate in the Student Congress. The four-day effort culminated in a 2011 Worlds Materials Summit Declaration delineating materials directions related to global access to clean energy and water in a sustainable way.

36 MATERIALS SCIENCE↗

Unique Methodologies for Nano/Micro Manufacturing Job Training Via Desktop Supercomputer Modeling and Simulation

This project establishes an initiative in high speed (Teraflop)/large-memory desktop supercomputing for modeling and simulation of dynamic processes important for energy and industrial applications. It provides a training ground for employment of current students in an emerging field with skills necessary to access the large supercomputing systems now present at DOE laboratories. It also provides a foundation for NIU faculty to quantum leap beyond their current small cluster facilities. The funding extends faculty and student capability to a new level of analytic skills with concomitant publication avenues. The components of the Hewlett Packard computer obtained by the DOE funds create a hybrid combination of a Graphics Processing System (12 GPU/Teraflops) and a Beowulf CPU system (144 CPU), the first expandable via the NIU GAEA system to ~60 Teraflops integrated with a 720 CPU Beowulf system. The software is based on access to the NVIDIA/CUDA library and the ability through MATLAB multiple licenses to create additional local programs. A number of existing programs are being transferred to the CPU Beowulf Cluster. Since the expertise necessary to create the parallel processing applications has recently been obtained at NIU, this effort for software development is in an early stage. The educational program has been initiated via formal tutorials and classroom curricula designed for the coming year. Specifically, the cost focus was on hardware acquisitions and appointment of graduate students for a wide range of applications in engineering, physics and computer science.

Kimball, Clyde↗

Hand-Stacking and Remote Approach to Critical Using the Planet Assembly [Slides]

Goals: •To ensure students gain a working knowledge of how to apply the “½-way ” and “¾” safety rules for performing a “hand-stack” operation. •To ensure students gain a working knowledge of how changes in moderator and reflector geometry affect the criticality of a system. •To ensure students gain experience using the Inhour equation relating reactivity and reactor period.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗

Mechanism of Synthesis of Ultra-Long Single Wall Carbon Nanotubes in Arc Discharge Plasma

In this project fundamental issues related to synthesis of single wall carbon nanotubes (SWNTs), which is relationship between plasma parameters and SWNT characteristics were investigated. Given that among plasma-based techniques arc discharge stands out as very advantageous in several ways (fewer defects, high flexibility, longer lifetime) this techniques warrants attention from the plasma physics and plasma technology standpoint. Both experimental and theoretical investigations of the plasma and SWNTs synthesis were conducted. Experimental efforts focused on plasma diagnostics, measurements of nanostructures parameters, and nanoparticle characterization. Theoretical efforts focused to focus on multi-dimensional modeling of the arc discharge and single wall nanotube synthesis in arc plasmas. It was demonstrated in experiment and theoretically that controlling plasma parameters can affect nanostucture synthesis altering SWNT properties (length and diameter) and leading to synthesis of new structures such as a few-layer graphene. Among clearly identified parameters affecting synthesis are magnetic and electric fields. Knowledge of the plasma parameters and discharge characteristics is crucial for ability to control synthesis process by virtue of both magnetic and electric fields. New graduate course on plasma engineering was introduced into curriculum. 3 undergraduate students were attracted to the project and 3 graduate students (two are female) were involved in the project. Undergraduate student from Historically Black University was attracted and participated in the project during Summer 2010.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗

FLC Nomination: Carole Rutten

STEM Mentorship Award: Given to an individual who may or may not be a direct employee of a government laboratory or facility in the Mid Continent Region, but has demonstrated exceptional character, mentorship, and creativity in the areas of science and math or by promoting the development of young people in grades K-12 or higher in technical career fields. Contributions must be unique and show measurable benefit to the laboratory, school system/students and must have occurred within the past three calendar years. Los Alamos National Laboratory (LANL) would like to nominate Carole Rutten for the FLC STEM Mentorship Award. Carole has been responsible for the Los Alamos National Security, LLC (LANS) Institutional Education Investments since 2007. In 2012, Carole initiated and led the review of the education programs and investments’ impact in Northern New Mexico. An Education Impact Study conducted in 2010 indicated that there was an abundance of STEM Programs for kindergarten through sixth grade (K-6) students, but relatively few STEM Programs existed for students in middle school and beyond. To address this gap, Carole worked with LANS to focus its education investments on programs for middle and high school students to better prepare them for collegiate studies leading to STEM careers.

99 GENERAL AND MISCELLANEOUS↗

High Energy Density Physics and applications with a state-of-the art compact x-pinch

Recent advances in technology has made possible to create matter with extremely high energy density (energy densities and pressure exceeding 10 11 J/m 3 and 1 Mbar respectively). The field is new and complex. The basic question for high energy density physics (HEDP) is how does matter behave under extreme conditions of temperature, pressure, density and electromagnetic radiation? The conditions for studying HEDP are normally produced using high intensity short pulse laser, x-rays, particle beams and pulsed power z-pinches. Most of these installations occupy a large laboratory floor space and require a team consisting of a large number of scientists and engineers. This limits the number of experiments that can be performed to explore and understand the complex physics. A novel way of studying HEDP is with a compact x-pinch in university scale laboratory. The x-pinch is a configuration in which a pulsed current is passed through two or more wires placed between the electrodes making the shape of the letter ‘X’. Extreme conditions of magnetic field (> 200 MGauss for less than 1 ns), temperature (1 keV) and density (~ 10 22 cm -3 ) are produced at the cross-point, where two wires make contact. Further, supersonic jets are produced on either side of the cross-point. The physics of the formation of the plasma at the cross-point is complex. It is not clear what role radiation plays in the formation of high energy density plasma (>> 10 11 J/m 3 ) at the cross-point. Nor it is understood how the supersonic jets are formed. Present numerical codes do not contain complex physics that can take into account some of these aspects. Indeed, a comprehensive experimental study could answer some of the questions, which are relevant to wide-ranging fields such as inertial confinement fusion, astrophysical plasmas, high intensity laser plasma interactions and radiation physics. The main aim of the proposal was to increase the fundamental understanding of high energy density physics and particularly address the key issues associated with x-pinches, which include radiation transport, energetic particle transport, supersonic jet formation, using state-of-the-art compact pulsed power drivers. All the primary objectives of the proposed work were met. These objectives include: • Understanding of the fundamental physics of hot and dense plasma formation, implosion to less than 1 µm size due to the radiation enhanced collapse and energetic electron heating, • Study of the jet formation mechanism, which is of interest due to the astrophysical jets and deposition of energy by energetic electrons in jets, • Characterization of an x-pinch as a point x-ray source for the phase contrast radiography of beryllium cryogenic targets for the National Ignition Facility (NIF) experiments. The work carried out included a strong educational component involving both undergraduate and graduate students. Several undergraduate students from University of California San Diego participated in this project. A post-doctoral fellow, Dr. Simon Bott and two graduate students, David Haas and Erik Shipton contributed to every aspect of this project. The success of the project can be judged from the fact that fifteen peer-reviewed papers were published in high quality journals. In addition several presentations were made to a number of scientific meetings.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗

Boston Architectural College Urban Sustainability Initiative

The Boston Architectural College's Urban Sustainability initiative is a demonstration project as defined by the National Energy Technology Laboratory. BAC's proposed project with the U.S. Department of Energy - NETL, is a large part of that overall initiative. The BAC's Urban Sustainability Initiative is a multi-part project with several important goals and objectives that will have a significant impact on the surrounding neighborhood including: energy conservation, reduction of storm water runoff, generation of power through alternative energy sources, elimination/reduction of BAC carbon footprint, and to create a vehicle for ongoing public outreach and education. Education and outreach opportunities will serve to add to the already comprehensive Sustainability Design courses offered at BAC relative to energy savings, performance and conservation in building design. At the finish of these essential capital projects there will be technical materials created for the education of the design, sustainability, engineering, community development and historic preservation communities, to inform a new generation of environmentally-minded designers and practitioners, the city of Boston and the general public. The purpose of the initiative, through our green renovations program, is to develop our green alley projects and energy saving renovations to the BAC physical plant, to serve as a working model for energy efficient design in enclosed 19th century and 20th century urban sites and as an educational laboratory for teaching ecological and sustainable technologies to students and the public while creating jobs. The scope of our project as it relates to the BAC and the U.S. Department of Energy- NETL combined efforts includes: Task I of the project is Phase II (Green Alley). Task I encompasses various renovation activities that will demonstrate the effectiveness of permeable paving and ground water recharge systems. It will aid in the reduction of storm water runoff into the Charles River Basin in one of its most significantly polluted sections and, will provide a green renovation mechanism for the redirected storm water of a public alley way. This activity is designed to improve the quality of water recharging the ground water and protecting the vulnerable wood pilings under many of the historic masonry buildings in Boston's Back Bay. Sustainable design research and system monitoring opportunities will also be incorporated, providing ongoing tools for public outreach and education through innovative signage and "virtual tour" technology. The monitoring will include a "building performance dash board" that reflects real time operating conditions and improvements in environmental and economic performance to be prominently displayed on the face of our 320 Newbury Street building (approximately 1.5 million people walk by annually). The project site and demonstration area is located at the rear of 951 Boylston Street, Boston, MA 02115 and the parking area adjacent to Public Alley #444 in Boston's historic Back Bay. Task II of the project is Geothermal Solution. This task involves the installation of approximately seven Geothermal wells which will tap into the earth's constant underground temperatures to provide air-conditioning and heating for BAC facilities. The environmentally friendly geothermal system uses no fossil fuel, produces no emissions and runs silently, providing a sustainable model for commercial and residential buildings throughout Boston. Ultimately the combination of this project and other projects will assist in making the BAC "carbon-neutral", and could generate enough additional energy to provide free power to the Engine 33 and Ladder 15 Firehouse located at 941 Boylston Street. The project is located at the rear of 951 Boylston Street, Boston, MA 02115 and the parking area adjacent to Public Alley #444 in Boston's historic Back Bay. Task III of the project is the Sustainability Design Curriculum at the BAC. The BAC is the nation’s largest independent, multi-disciplinary college of spatial design, and a leader in sustainable design education. The Sustainabiltiy Design program, in particular, focuses on energy efficiency,energy performance, energy modeling, energy and air quality principles, green building, renewable energy alternatives and much more. Additionally, the Urban Sustainability Initiative has an objective of providing courses relative to the BAC's demonstration project with DOE, the project’s period of performance activities, subsequent performance data and anticipated sustainability teaching tools. In keeping with BAC's practice based curriculum, students have been involved in the discussion and planning of this project since its inception and sustainability issues have become a part of other programs throughout the college as well. Students will continue to benefit from this hands-on learning opportunity. The project is located at 320 Newbury Street Boston, MA 02115. Task IV of the project is Program Management and Reporting. This task will involve BAC's oversight and general management of the entire project including subcontract administration, contracts administration, technical and financial reporting, design and renovation assistance, other deliverables in accordance with the Federal Assistance reporting Checklist and other contractual obligations and provisions.

15 GEOTHERMAL ENERGY↗

Nanoscience Research Internships in Illinois

NanoBusiness Talent Project Summary Report The NanoBusiness Alliance created the NanoBusiness Talent Program to ensure the future vitality of domestic scientists and entrepreneurs by engaging advanced high school students in cutting-edge nanotechnology development. This program commenced on September 1, 2008 and ran through August 31, 2010 with a very successful group of students. Several of these students went on to Stanford, Harvard and Yale, as well as many other prestigious Universities.

99 GENERAL AND MISCELLANEOUS↗

Phosphors for near UV-Emitting LED's for Efficacious Generation of White Light

1) We studied phosphors for near-UV (nUV) LED application as an alternative to blue LEDs currently being used in SSL systems. We have shown that nUV light sources could be very efficient at high current and will have significantly less binning at both the chip and phosphor levels. We identified phosphor blends that could yield 4100K lamps with a CRI of approximately 80 and LPWnUV,opt equal to 179 for the best performing phosphor blend. Considering the fact that the lamps were not optimized for light coupling, the results are quite impressive. The main bottleneck is an optimum blue phosphor with a peak near 440 nm with a full width half maximum of about 25 nm and a quantum efficiency of >95%. Unfortunately, that may be a very difficult task when we want to excite a phosphor at ~400 nm with a very small margin for Stokes shift. Another way is to have all the phosphors in the blend having the excitation peak at 400 nm or slightly shorter wavelength. This could lead to a white light source with no body color and optimum efficacy due to no self-absorption effects by phosphors in the blend. This is even harder than finding an ideal blue phosphor, but not necessarily impossible. 2) With the phosphor blends identified, light sources using nUV LEDs at high current could be designed with comparable efficacy to those using blue LEDs. It will allow us to design light sources with multiple wattages using the same chips and phosphor blends simply by varying the input current. In the case of blue LEDs, this is not currently possible because varying the current will lower the efficacy at high current and alter the color point. With improvement of phosphor blends, control over CRI could improve. Less binning at the chip level and also at the phosphor blend level could reduce the cost of SSL light sources. 3) This study provided a deeper understanding of phosphor characteristics needed for LEDs in general and nUV LEDs in particular. Two students received Ph.D. degrees and three undergraduates participated in this work. Two of the undergraduate students are now in graduate school. The results were widely disseminated – 20 archival journal publications (published, accepted or in preparation) and three conference proceedings resulted. The students presented their work at 11 different national/international conferences (32 oral or poster presentations) and the PI’s delivered 12 invited, keynote or plenary lectures.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗