National Science Foundation - College of Engineering & Natural Sciences

National Science Foundation

Better lighting for all

Have you ever shuddered at the tinny quality of light-emitting diodes (LEDs)? Despite their harsh and unflattering glare, you likely nevertheless screw them into your lamps because you know they last a lot longer and use far less energy than conventional incandescent bulbs and fluorescent tubes. If Peifen Zhu has her way, however, one day we might all be happily basking in the glow of LED lamplight that is calm, cool and doesn’t make your skin crawl.

physics professor Peifen Zhu in her lab with research equipment
Professor Peifen Zhu

Zhu is an assistant professor of physics and engineering physics at The University of Tulsa. Earlier this year, the National Science Foundation (NSF) awarded to Zhu a five-year Faculty Early Career Development (CAREER) grant to support her investigation of lead-free pseudohalide/halide perovskites for next-generation white LEDs. Metal halide perovskites, she explained, are promising semiconductor materials for potential application in optoelectronic devices – that is, devices that either emit or detect light.

“LED technology based on metal halide perovskites is still in its early stage,” noted Zhu. “Two of the main barriers to its practical applications are problems with stability and the common inclusion of lead. Continued innovation and breakthroughs are needed to achieve LED’s full potential.”

computer monitors, micro-drilling equipment and other tools in Professor Zhu's lab
Micro-drilling equipment

The objective of Zhu’s research on solid-state lighting technology is to develop highly efficient, environmentally friendly luminescent materials by using earth-abundant elements (e.g., carbon, nitrogen, oxygen) and low-cost, large-scale methods to replace the yellow phosphors that make conventional LEDs cast such unpleasant light. “My hope,” Zhu said, “is that this theoretical and experimental work will, ultimately, boost the widespread adoption of white LEDs that have superior color quality and, thereby, reduce our energy consumption.”

Training future scientists

Built into Zhu’s research program is educational training for undergraduate and graduate TU students in physics, material science, electrical engineering and mechanical engineering. Currently, four graduate students and one undergraduate student are collaborating with Zhu her Lab for Emerging Materials and Devices. In fact, Zhu and her students have been working on the LED project since before the NSF grant. The team has been nothing if not prolific, and their findings have been published in several prestigious journals, including Advanced Optical Materials, ACS Applied Materials & Interfaces, Nano Research, Journal of Colloid and Interface Science, Optics Express and Journal of Physical Chemistry.

computer monitor measuring LED
LED measurement

“I have been working with Professor Zhu since June 2017,” said Gopi Adhikari, a doctoral candidate in physics at TU. “Dr. Zhu has been instrumental in my development as a scientist. She is dynamic, enthusiastic and always ready to help students without hesitation as both a teacher and research mentor. Two of the things that stand out for me particularly strongly are Dr. Zhu’s respect for each student and her passion for their success. I have learned so much from her and I am grateful to be involved in the research she is carrying out.”

One of the novel aspects of Zhu’s program is that it will involve students from local middle and secondary schools. “I plan to invite budding scientists to conduct experimental work at TU during the summer,” noted Zhu, “thereby giving them hands-on experience in photonic research methodologies before they ever set foot at university.”

In fact, Zhu has some history mentoring such students. During the summers of 2017 and 2018, a high school student named William Wang undertook experimental work in her lab. Not only did this lead to scholarly publications and presentations, but Wang also won several national and international competitions, including the Google Science Fair. Today, he is an undergraduate student at Stanford University.


Does research in the most fundamental of the sciences interest you? If so, learn more about the pathways and opportunities offered by TU’s Department of Physics and Engineering Physics.

 

 

TU’s Benjamin James and Jordan Sosa receive NSF Graduate Research Fellowships

Two students from The University of Tulsa have been awarded Graduate Research Fellowships from the National Science Foundation. TU’s 2019 recipients are Jordan Sosa, an engineering physics senior from Florissant, Missouri, and Benjamin James, a computer science senior, from St. Louis, Missouri.

The NSF Graduate Research Fellowship Program recognizes and supports outstanding graduate students in the science, technology, engineering and mathematics disciplines who are pursuing research-based master’s and doctoral degrees at accredited institutions in the United States. Fellows receive a three-year annual stipend of $34,000 along with a $12,000 education allowance for tuition and fees. Other benefits include opportunities for international research and professional development and the option to conduct research at any accredited U.S. institution of graduate education.

Jordan Sosa

jordan sosaSosa currently focuses on materials research and metallic materials as a student in the TU Department of Mechanical Engineering. As a TU undergraduate, Sosa has received valuable experience in physics, materials science and engineering as a visiting researcher at West Virginia University, Oklahoma State University-Tulsa and the University of Wisconsin-Madison. In addition to his academic and research agenda, Sosa has served in leadership roles for TU’s Society of Hispanic Professional Engineers and the Society of Physics Students, attended the National Institute for Leadership Advancement and helped host a Noche de Ciencias, or “Night of Sciences” community event that invited local public school children to learn about STEM degrees.

“These experiences have instilled a stronger desire in me to pursue a higher degree so I can develop a stronger understanding of STEM and provide others with access to that education,” he said.

He plans to earn a Ph.D. degree from Harvard University in materials science and engineering in research fields of energy storage and eventually work in a laboratory or the research and development department of a materials technology company.

Benjamin James

benjamin jamesJames has performed research in the bioinformatics subfield computational genomics, which emphasizes the use of computational and statistical techniques such as algorithms and machine learning/artificial intelligence to solve biological problems.

“At TU, under the mentorship of Dr. Hani Girgis, I created intelligent and adaptive software systems to compare and cluster nucleotide sequences, especially long, genome-length sequences, as a method of in silico data analysis for computational biologists,” James said.

The clustering algorithm currently is used by biologists in multiple pipelines, including groups of third-generation sequencing reads and grouping of microbial communities. James plans to attend graduate school at MIT and work independently on bioinformatics research projects that can have a positive impact on society.