Vitals
Current affiliation: Texas A&M University
Age: 40
PhD alma mater: University of Michigan
If I were an element, I’d be: “Nitrogen. My fate seems to be intertwined with nitrogen; from my PhD work to the present, all of my academic achievements have, in one way or another, involved nitrogen.”
My favorite movie is: “A Beautiful Mind, starring Russell Crowe, based on the life of John Forbes Nash Jr.”
Abdoulaye Djire remembers evenings from his childhood, crowding around his family’s small TV along with several neighbors and praying that the slowly dimming screen wouldn’t go dark before the movie ended. The TV ran at night on alkaline batteries fed by two solar panels on the roof of his house, which was the only one with electricity in off-grid Sebenikoro, Mali, 10 km west of the country’s capital, Bamako. “The problem with alkaline batteries is that they don’t hold a lot of energy,” he says with a chuckle. “This was my introduction to renewable electricity.”
Now at Texas A&M University (TAMU), Djire is considered a founder of a new class of 2D materials that could transform energy storage and open pathways to make sustainable fuels from carbon dioxide, air, and water.
Djire’s group—which he has acronymically named the DJIRE lab, for Discovery Journey to Innovative Renewable Energy—leads world research on nitride MXenes, which Djire first synthesized as a postdoctoral researcher at the National Renewable Energy Laboratory (NREL), now called the National Laboratory of the Rockies (NLR). “He was a stellar postdoc,” says Nathan Neale, manager of NLR’s interfacial materials chemistry group. “He came in wanting to do something very high risk, high reward. It’s the hallmark of someone who wants to push the boundaries of science and push themselves.”
That drive runs in the family. Djire’s father was the first electrical engineer at Mali’s first radio and TV station. His mother didn’t have a formal education but ran a secondhand clothing business while raising nine kids. In high school, Djire excelled in chemistry, physics, and math. “Half my class would come to my house for lessons,” he says. When his mother’s business boomed, the opportunity arose for him to come to the US to study.
After a year of English lessons in Houston, Djire pursued a bachelor’s degree in chemical engineering at Prairie View A&M University and then started graduate school at the University of Michigan in 2011. For his PhD, Djire studied the charge-storing properties of transition metal carbide and nitride compounds for high-energy-density supercapacitors.
Also in 2011, researchers at Drexel University announced the discovery of MXenes, a family of layered 2D materials composed of a stack of atom-thick transition metal sheets interleaved with carbon sheets. The 2D materials caught Djire’s interest. Their composition was like the bulk carbides and nitrides he was experimenting with, but they had unique properties and tunable chemistries for use in catalysis, energy storage, sensors, and photonic devices.
Djire knew that bulk metal nitrides are better than carbides at energy storage and conversion because of nitrogen’s extra electron and reactivity. “So I knew that having nitride forms of the 2D MXene will be more advantageous.”
But others had tried to make nitride MXenes and failed. The process involves etching aluminum from precursor materials to create the stack of atom-thick sheets. This works with carbide precursors, but nitrides have stronger aluminum–transition metal bonds. Researchers tried etching with hydrofluoric acid (HF), but they ended up removing nitrogen along with aluminum.
Djire doubled down on nitride MXenes at NREL. He ditched toxic HF and found that etching with oxygen-laced molten fluoride salts did the trick. Oxygen weakened the bonds, allowing the fluoride salts to carve out aluminum. The nitride MXenes he made showed high catalytic activity and semiconducting properties.
At TAMU, Djire’s group has found that nitride MXenes catalyze the conversion of nitrogen and hydrogen from air and water to form ammonia, an alternative to the Haber-Bosch process that is far less emission intensive. He is now leading work to understand the materials’ fundamental properties, harnessing them to convert CO2 to fuels, creating high-energy magnesium batteries, and using machine learning to synthesize new types of nitride MXenes.
He is also busy raising funds for his nonprofit, The Djire Foundation, which will provide scholarships to international students to help them qualify for in-state tuition in Texas, which is a quarter of that for out-of-state students.
Djire wouldn’t have been able to come to the US without a similar scholarship—or without the support from his parents, especially his mother, he says. “My mom was the backbone.” Even though his father was the engineer, he says, those rooftop solar panels were her idea.
