Graduate student Joshua Engler (Tolbert group) has been awarded the 2023 National Defense Science and Engineering Graduate (NDSEG) Fellowship, one of the country’s most prestigious honors for graduate students in the fields of Science Technology, Engineering and Mathematics or STEM.
Engler is among 165 students from across the country, and one of four from UCLA, who were awarded the highly competitive fellowship this year. The fellowship pays for the awardees’ tuition and university fees for three years, along with a monthly stipend and available funds for research and travel expenses.
Engler received his bachelor’s degree in chemistry from Haverford College, where he worked as an undergraduate researcher with Professor Alexander Norquist synthesizing novel amine-templated metal oxide crystals and creating datasets of reaction parameters and outcomes from my experiments to train machine learning algorithms to help more efficiently explore underexplored chemical space. He joined the UCLA Chemistry & Biochemistry graduate program in 2022, joining Professor Sarah Tolbert’s group.
In the Tolbert lab, Engler works on synthesizing and characterizing a class of energy storage materials called pseudocapacitors. “The goal of making these materials is to create energy storage materials that combine the high energy density of classic battery materials with the short charging times and long cycle life of supercapacitors,” Engler said. “The type of pseudocapacitors that I am working on are electrochemically similar to traditional batteries. They generate current by lithium ions moving across an electrolyte to an electrode. The specific electrode that I work on in MoS2. MoS2 is a layered material, which makes it an attractive lithium-ion battery electrode because it can intercalate lithium ions into the gaps between MoS2 layers.”
“Lithium ions intercalating and de-intercalating during the charge-discharge process cause phase transitions in the MoS2 material, leading to slower charge storage kinetics and degradation of the material,” he explained. “It has been shown that nano-structuring MoS2 increases the interlayer spacing and suppresses the phase transition, leading to improved overall battery performance. My goal is to closely examine the relationships between particle size, interlayer spacing, and phase transitions to gain fundamental insight into how these factors affect battery performance. I synthesize different particle sizes of MoS2 using different reaction temperatures and conditions, and then dope these materials with different ions (metals, amines, organic molecules) into the MoS2 layers to increase the interlayer spacing. I then test the electrochemical performance of these materials by testing them as a battery electrode to make fundamental conclusions about how the material properties of particle size and interlayer spacing affect battery performance.”
After graduating Engler plans to work in industry, doing research and development in either energy storage or alternative energy.
“I am passionate about materials chemistry and the discovery of new materials, and my goal is to apply that to the development of new materials that will lead to more sustainable forms of energy production and storage that will significantly improve our reliance on fossil fuels and decrease our carbon emissions,” Engler said.
Penny Jennings, UCLA Department of Chemistry & Biochemistry, penny@chem.ucla.edu.
