Printing infrastructure for cleaner energy

When chemist Joseph DeSimone opened his lab at the Stanford School of Engineering in 2020, he was working with 3D printing systems capable of printing details finer than the width of a human hair. Still, the systems were not precise enough for the revolutionary approaches DeSimone envisioned.

Since then, DeSimone and his team have designed systems that print materials with features as narrow as 10 microns – about one-tenth the width of a human hair – and have demonstrated a technique for making them in large quantities.

Through DeSimone’s two-step fabrication approach, which involves printing a polymer structure using light and then subjecting it to high temperatures, engineers can precisely control material properties, including the quantity and size range of pores and how well they transport heat.

The lab just needed, as DeSimone likes to say, “a killer app,” or an ideal application of their materials to an existing problem.

In late 2024, DeSimone Lab member Philip Onffroy, a PhD student in chemical engineering, attended an event at the Stanford Sustainability Accelerator, based in the Doerr School of Sustainability. The Accelerator helps Stanford teams turn their research into innovations that address global sustainability challenges, such as decarbonizing industrial manufacturing and the electricity sector.

Onffroy, who is also a Knight-Hennessy scholar, hoped the Accelerator could help position the DeSimone Lab’s materials for high-impact sustainable energy applications. Onffroy and DeSimone applied for an Accelerator grant with fellow lab members Jacob Dobson, a PhD student in chemistry in the School of Humanities and Sciences, and Maria Dulay, lab manager and senior research scientist in the School of Medicine. The team received funding to pursue potential applications for their materials in the energy industry.

Related: Engineering precision components for sustainable energy systems
Now, they’ve found a possible “killer app”: In February 2026, Stanford filed a patent for the use of their hollow, latticed capsules in nuclear fusion and fission fuel containment.

Fusion, the nuclear reaction that powers the sun, is one of the most ambitious projects in sustainable energy. If realized at a large scale, fusion reactors would provide zero-emission power without the long-lasting radioactive waste of traditional fission reactors.

DeSimone’s team is collaborating with researchers at SLAC National Accelerator Laboratory to study how their capsules would perform in inertial confinement fusion, or ICF, reactors, which researchers have been developing for decades.

In an ICF reactor, capsules are filled with liquid deuterium and tritium fuel, then blasted with lasers. This intense light energy causes the capsules to implode, generating such high temperatures and pressure that the fuel atoms fuse to produce helium and release energy.

In 2022, scientists at Lawrence Livermore National Laboratory announced they had successfully produced this reaction in a lab and, for the first time, briefly generated more energy than it took to start the reaction. Onffroy said his team hopes that their capsules will be part of the effort to translate those experimental results into a commercially viable system.

Because the lasers in an ICF reactor are positioned to hit the capsules precisely, any structural flaw in a capsule material can affect the uniformity of fuel compression and energy output, DeSimone said. With foams or aerogels, the materials used in current experimental approaches, the pores vary from capsule to capsule, much like the unique patterns of a snowflake.  

But DeSimone’s capsules are digitally designed to be identical every time they’re printed. “We don’t make snowflakes. We make precision particles,” DeSimone said.

Before receiving Accelerator support, the team hadn’t considered fusion as a potential application for their materials, Onffroy said. But expert support staff at the Accelerator, including managing director Albert Chan and sustainability technology and business analyst Mana Iwata, encouraged their interest in the nuclear industry. When DeSimone’s team connected with researchers at SLAC, they worked together to identify the opportunity to make materials for ICF reactors.

DeSimone and colleagues are also exploring opportunities to create materials for nuclear fission systems, batteries for energy storage, and electrically heated chemical reactors.

The Accelerator “gave us an opportunity to take our platform and talk to different potential users who have the mindset of sustainability,” DeSimone said.

DeSimone’s team has also connected with other teams that are supported by the Accelerator. Onffroy said he’s spoken with students in business and economics who encourage him to consider different aspects of scaling technologies. In turn, he’s shared his expertise in materials.

“I feel, especially now with all the AI, that a little ‘NI’ – natural intelligence – is going to be more important than ever,” DeSimone said. “The perspectives of the people coming together and the diversity of their experiences are invaluable. We think that’s our secret sauce of why our ideas work.”

Joseph DeSimone is the Sanjiv Sam Gambhir Professor of Translational Medicine and a professor of radiology at Stanford School of Medicine, and a professor of chemical engineering at the Stanford School of Engineering. Max Saccone, a former project team member and postdoctoral scholar in chemical engineering at the School of Engineering and radiology at the School of Medicine, is now affiliated with the University of Colorado at Boulder. Stanford University does not endorse any non-Stanford entities, programs, products, or services listed in the article.