The chemistry that could keep the world fed

There was a time when nations went to war over islands layered with bird droppings. In the 19th century, deposits of guano— rich in phosphorus and nitrogen— were so valuable that they reshaped geopolitics. Today, the stakes are no less profound. Without phosphorus and nitrogen-based fertilisers, global agriculture would collapse; without them, as Karthish Manthiram puts it, “we would starve”. More subtly, the same chemistry underpins modern life, from plastics to pharmaceuticals to the batteries in our pockets.

It is this invisible yet foundational chemical world that has earned Manthiram, a professor at California Institute of Technology, the Infosys Prize 2025 in physical sciences. His work pioneers a radically different way of making essential chemicals— one that could reshape global supply chains and reduce dependence on fossil fuels at a time when geopolitical tensions, including the ongoing instability in West Asia, continue to threaten fertiliser availability and prices.

At the heart of Manthiram’s research is a simple idea: replace petroleum with air and water. “Whether it’s the plastic of a water bottle, the fuel you put into a car, or the pharmaceuticals we ingest, so many of these things come from a petroleum-based supply chain,” he explains. “The vision of my group is to replace that.” Instead of starting with a barrel of oil, his lab begins with nitrogen, carbon dioxide and water—molecules that are abundant and sustainable.

The challenge lies in persuading these stable molecules to react. Nitrogen, which makes up nearly 80% of the air we breathe, is notoriously inert. “It’s a very happy bond,” he says of the nitrogen triple bond. “Breaking it is the hardest step.” For over a century, industry has relied on the Haber– Bosch process, a method that uses high temperatures, high pressures and fossil fuels to convert nitrogen into ammonia—the basis of fertilisers. It is effective but carbon-intensive.

Manthiram’s approach replaces this brute-force chemistry with electricity. “We are establishing a paradigm where electricity can be used instead,” he says. “You can operate at room temperature, at ambient pressure, and apply a voltage.” The implications are profound. Not only could this eliminate carbon emissions from fertiliser production, it could also decentralise it. Instead of massive industrial plants, fertilisers could be produced locally, even by farming communities themselves using modular devices powered by renewable energy.

This shift comes at a critical moment. Fertiliser supply chains remain vulnerable to geopolitical disruptions, particularly in West Asia, a region central to global energy markets. Any shock to natural gas supply—the key input for conventional ammonia production—ripples through agriculture worldwide. Manthiram’s electrochemical routes offer a way to insulate food systems from such volatility.

Continuing family legacy
Manthiram is the son of Arumugam Manthiram, a pioneering materials scientist known for his work on lithium-ion batteries. Karthish grew up immersed in science. His father’s discovery of lithium iron phosphate—now used in a significant share of global batteries—took decades to reach commercial scale, a lesson in patience that clearly left an imprint. “It shows just how long it takes,” he reflects.

That legacy was visible recently when the family gathered in India for the Infosys Prize ceremony. It was also a reminder of how scientific ambition often runs deep within families.

Yet Manthiram has charted his own path, often embracing ideas others dismissed. When he first proposed his research direction, he recalls, “people laughed at me… they said others had tried this and failed.” The field of electrochemical ammonia synthesis was littered with irreproducible results. “That’s the kind of thing that keeps a scientist up at night,” he says.

His breakthrough came in 2019, when his team developed a new electrode design that dramatically accelerated reaction rates. By rethinking how nitrogen reaches the reaction site, they overcame a fundamental bottleneck. “Science is about getting from 0 to 1,” he says. “Then others take it from 1 to 10.” Indeed, labs around the world have since built on his work, with some even launching startups.

Another key advance addressed cost. Early systems relied on lithium, an expensive and increasingly scarce material due to demand from electric vehicles. Manthiram’s group found a workaround by pairing sodium with titanium—an abundant and far cheaper combination. “Sodium alone can’t break the nitrogen bond,” he explains. “But give it a partner like titanium, and it works.” The result is a pathway that could make sustainable fertiliser production viable.

Beyond ammonia, his lab is also advancing the production of epoxides—key building blocks for plastics, textiles and antifreeze. These “hidden chemical champions”, as he calls them, are everywhere, yet their current manufacturing processes are environmentally damaging. His electrochemical methods not only clean up production but also generate hydrogen as a useful by-product, improving overall economics.

The dual focus on fundamental science and engineering scalability is precisely what set his work apart for the Infosys Prize jury. As one juror noted, the achievement lies not just in discovering a new chemical pathway, but in envisioning how it could be implemented without “heavy machinery” or pollution.

Commercialisation, however, remains a careful balancing act. While venture capital interest is strong, Manthiram is cautious. “I want to de-risk one or two more pillars before we take this out of the lab,” he says.