Aluminum alloys keep airplanes flying, but when they corrode, the consequences are costly and dangerous. To tackle the concern, a team of Johns Hopkins chemical and biomolecular engineering students has developed Ze[r]ossion—an advanced, environmentally safer coating that promises to extend the life of aerospace aluminum while eliminating the toxic chemicals commonly used today.
The students will present their prototype on April 28 at the Whiting School of Engineering’s Design Day, an annual event showcasing students’ solutions to real-world problems.
“Originally, the idea grew out of concerns about bridge corrosion, as one of our teammates is interested in civil engineering, but as we worked through the course we realized aerospace presented a very specific need,” says Lavanya Gupta. “The environmental and worker safety problems with current corrosion inhibitors made it clear that this application deserved attention, so we pivoted. The underlying science is the same, and that’s exciting because Ze[r]ossion could be adapted to many industries.”
Corrosion of aluminum alloys poses serious safety risks. Current state‑of‑the‑market chromate coatings are effective but contain highly carcinogenic compounds, creating regulatory and occupational health pressures to find alternatives. Ze[r]ossion addresses this gap by using zeolites loaded with molybdate ions that are released at active corrosion sites on the metal surface.
“Our product is a powder of molybdate‑loaded zeolite that can be incorporated into existing coating workflows for aluminum alloys,” says Rebecca Kottke. “The zeolite acts like a reservoir—when corrosion starts, molybdate ions are delivered to neutralize it. In tests, this controlled release doubles the effective lifespan of the coating while removing the toxicity concerns associated with chromates.”
The team’s manufacturing approach has been designed to be compatible with current industrial processes. They load commercial zeolite with molybdate through an ion‑exchange procedure to reach a target concentration, producing Ze[r]ossion in a form that can be mixed into coatings.
“One of the hands-on parts of the project was optimizing the ion exchange so we could reliably reach the desired loading,” says Jackson Webster. “It’s a scalable process, and because Ze[r]ossion is a powder, it can slot into existing manufacturing lines without major retraining or capital investment.”
The team says that Ze[r]ossion stands out for both safety and performance. Chromates, long used because of their durability, are classified as carcinogens and pose high risks to workers and the environment. Ze[r]ossion replaces those compounds with molybdate‑based chemistry that eliminates the same toxicity while improving longevity through controlled ion delivery.
“Regulatory pressure is pushing industry away from chromates, but many alternatives trade performance for safety,” says Victor Wu. “We believe Ze[r]ossion offers the best of both worlds—it’s safer for people and the planet, and it provides better protection for the aircraft.”
Although the students will take different paths after graduation, they are optimistic about the project’s future impact.
“We won’t be continuing Ze[r]ossion as a team, but we hope established companies in aerospace pick up and advance this approach,” says Gupta. “Seeing safer, more sustainable coatings become standard would be a meaningful outcome for all of us.”