Daniel
Sobek

The Story

A chemist said one word. It became a company.

Daniel Sobek runs a company whose entire technical thesis fits on a Post-it note. When he asked his co-founder, materials chemist Sukanta Bhattacharyya, how to make a hydrogen electrolyzer more efficient and more durable at the same time, the reply was a single word: boron. That word is now the spine of 1s1 Energy, the Portola Valley startup Sobek leads as co-founder and CEO.

Today the work is about splitting water cheaply. Electrolyzers pass electricity through water to separate hydrogen from oxygen, and the membrane in the middle is where most of the energy is won or lost. 1s1's pitch is a boron-based ion-exchange membrane. Boron carries a negative charge that speeds the bonding of hydrogen ions and resists corrosion, which means the membrane can run harder and last longer. The company says electrolyzers built with it need only about 70 percent of the energy to make each kilogram of hydrogen compared with incumbent devices, and that customers in its pipeline see operating costs fall by roughly 60 percent.

That is a large claim in an industry that has humbled larger companies. Sobek is blunt about it. "Green hydrogen has been a hard industry to have success in," he has said. The interesting part is what he points to next: in tests, 1s1 says it already reaches the U.S. Department of Energy's efficiency milestone for proton-exchange-membrane electrolysis, a roughly 77 percent electrical efficiency target the DOE set for 2031. Reaching a 2031 number ahead of 2031 is the kind of detail that gets a 13-person company invited to pilot projects with steelmakers.

Before the water, the cells and the planes

Sobek did not arrive at hydrogen by the obvious road. Born and raised in Argentina, he went to MIT and stayed long enough to collect three degrees in three different engineering disciplines: a bachelor's in aeronautics and astronautics, a master's in mechanical engineering, and a PhD in electrical engineering and computer science, finished in 1997. His doctoral work, advised by Martha Gray and Stephen Senturia, was about measuring the optical properties of biological cells. A long way from electrolyzers, and a useful reminder that the man building hydrogen membranes started by trying to see inside a single cell.

After MIT he worked in microelectronics and microfluidics, the art of moving tiny volumes of fluid through tiny channels. In 2004 he founded Zymera and spent roughly a decade developing deep-tissue imaging meant to catch cancer earlier. He led other ventures too, as CEO of Aiken Biosciences and in a commercial role at Kernel. Around 2013 his attention turned toward hydrogen, and by late 2019 he and Bhattacharyya, his former Zymera partner, had started 1s1 with two more co-founders.

The founding team is the tell. Alongside Sobek and Bhattacharyya, who trained at the Max Planck Institute, there is Thiago Figueiredo, an economist focused on impact investment, and Professor T. Don Tilley, an organometallic chemistry heavyweight at UC Berkeley. A serial founder, a materials chemist, an impact-finance brain, and an academic who knows boron at the molecular level. The company holds two USPTO patents, 11,331,631 and 11,594,747, on the chemistry that ties them together.

Why steel, why Brazil

Cheap hydrogen only matters if someone needs a lot of it. Heavy industry does. Steelmaking is one of the hardest sectors to decarbonize, and it is exactly where 1s1 has aimed its early pilots. The company has run projects with Enel Green Power and lined up a $2.3 million electrolysis-stack project with CEEE-G in Brazil's Aneel research-and-development program, backed by CSN, the country's largest steel producer. When the 2024 seed round closed, Sobek framed it in those terms: "With this latest funding and our collaboration in the P&D Aneel project, we're one step closer to making green hydrogen a practical solution for decarbonising heavy industries."

The $1.4 million seed, announced in October 2024, was led by Faber Ventures and Asiri LLC, with Rumbo Ventures, City Light, and Gibson Lane GmbH joining. By then the team had expanded and opened operations in Brazil and Portugal, an unusual geographic spread for a company you could fit in a single conference room. The plan attached to the money is a second-generation electrolyzer that runs at higher temperatures, where efficiency gains get easier to find.

What keeps the story from being a one-product company is the chemistry's reach. Sobek talks about the same boron platform turning up in fuel cells, in solid-state batteries, in green-ammonia production, and even in pulling critical metals out of mining waste. Hydrogen is the wedge. The membrane is the business. Whether the claims hold at industrial scale is the question every deep-tech materials company eventually has to answer, and 1s1 is now in the part of the story where pilots become proof or they don't.

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