Rice University engineers have created a device that absorbs light, converts it into electricity, and then uses the electricity to split water molecules and generate hydrogen. Photo courtesy Gustavo Raskoksy/Rice University

A team of Rice University engineers have developed a scalable photoelectrochemical cell that converts sunlight into clean hydrogen at a record-setting pace.

The lab led by Aditya Mohite, an associate professor at Rice, published the findings in a study in Nature Communications late last month, in collaboration with the National Renewable Energy Laboratory, which is backed by the Department of Energy. In it, the team details how they created a device that absorbs light, converts it into electricity, and then uses the electricity to split water molecules and generate hydrogen.

Austin Fehr, a chemical and biomolecular engineering doctoral student at Rice and one of the study’s lead authors, says in a statement that the device "could open up the hydrogen economy and change the way humans make things from fossil fuel to solar fuel."

The device has a high solar-to-hydrogen conversion efficiency rate of 20.8 percent, which has yet to be reached with this type of technology, according to a release from Rice. In addition to its speed, this device is groundbreaking because it uses low-cost metal-halide perovskite semiconductors to power the reaction.

A photoreactor developed by Rice University’s Mohite research group and collaborators achieved a 20.8 percent solar-to-hydrogen conversion efficiency. Photo courtesy Gustavo Raskoksy/Rice University

“Using sunlight as an energy source to manufacture chemicals is one of the largest hurdles to a clean energy economy,” Fehr says in the statement. “Our goal is to build economically feasible platforms that can generate solar-derived fuels. Here, we designed a system that absorbs light and completes electrochemical water-splitting chemistry on its surface.”

To create the device the Mohite lab turned their existing solar cell into a reactor to split water into oxygen and hydrogen. However they continued running into issues with the semiconductors being "extremely unstable in water," according to Rice.

After two years of trials and errors, the team uncovered that by adding two layers of barriers to the semiconductors they were able to reach these record-breaking efficiency rates.

The team has also shown uses for their double barrier design with different semiconductors and for different reactions.

“We hope that such systems will serve as a platform for driving a wide range of electrons to fuel-forming reactions using abundant feedstocks with only sunlight as the energy input,” Mohite says in the statement.

The device joins another game-changing product shared in a Rice research study in recent weeks. Last month, a Rice University lab led by Haotian Wang, the William Marsh Rice Trustee Chair and an associate professor at Rice, shared their findings on how their simple plug-and-play device removes carbon dioxide from air capture to induce a water-and-oxygen-based electrochemical reaction.

Rice also recently opened registration for its 20th anniversary of Energy Tech Venture Day. Click here to register for the event on Sept. 21.

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ExxonMobil names new partner to bolster US lithium supply chain with offtake agreement

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Spring-headquartered ExxonMobil Corp. has announced a new MOU for an offtake agreement for up to 100,000 metric tons of lithium carbonate.

The agreement is with LG Chem, which is building its cathode plant in Tennessee and expects it to be the largest of its kind in the country. The project broke ground a year ago and expects an annual production capacity of 60,000 tons. The lithium will be supplied by ExxonMobil.

“America needs secure domestic supply of critical minerals like lithium,” Dan Ammann, president of ExxonMobil Low Carbon Solutions, says in a news release. “ExxonMobil is proud to lead the way in establishing domestic lithium production, creating jobs, driving economic growth, and enhancing energy security here in the United States.”

The industry currently has a lithium supply shortage due to the material's use in electric vehicle batteries and the fact that most of production happens overseas.

“Building a lithium supply chain with ExxonMobil, one of the world’s largest energy companies, holds great significance,” Shin Hak-cheol, CEO of LG Chem, adds. “We will continue to strengthen LG Chem’s competitiveness in the global supply chain for critical minerals.”

Per the release, the final investment decision is still pending.

Earlier this year, Exxon entered into another energy transition partnership, teaming up with Japan’s Mitsubishi to potentially produce low-carbon ammonia and nearly carbon-free hydrogen at ExxonMobil’s facility in Baytown.

Last month, the company announced it had signed the biggest offshore carbon dioxide storage lease in the U.S. ExxonMobil says the more than 271,000-acre site, being leased from the Texas General Land Office, complements the onshore CO2 storage portfolio that it’s assembling.

3 Houstonians named to prestigious list of climate leaders

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Three Houston executives — Andrew Chang, Tim Latimer, and Cindy Taff — have been named to Time magazine’s prestigious list of the 100 Most Influential Climate Leaders in Business for 2024.

As managing director of United Airlines Ventures, Chang is striving to reduce the airline’s emissions by promoting the use of sustainable aviation fuel (SAF). Jets contribute to about two percent of global emissions, according to the International Energy Agency.

In 2023, Chang guided the launch of the Sustainable Flight Fund, which invests in climate-enhancing innovations for the airline sector. The fund aims to boost production of SAF and make it an affordable alternative fuel, Time says.

Chang tells Time that he’d like to see passage of climate legislation that would elevate the renewable energy sector.

“One of the most crucial legislative actions we could see in the next year is a focus on faster permitting processes for renewable energy projects,” Chang says. “This, coupled with speeding up the interconnection queue for renewable assets, would significantly reduce the time it takes for clean energy to come online.”

At Fervo Energy, Latimer, who’s co-founder and CEO, is leading efforts to make geothermal power “a viable alternative to fossil fuels,” says Time.

Fervo recently received government approval for a geothermal power project in Utah that the company indicates could power two million homes. In addition, Fervo has teamed up with Google to power the tech giant’s energy-gobbling data centers.

In an interview with Time, Latimer echoes Chang in expressing a need for reforms in the clean energy industry.

“Addressing climate change is going to require us to build an unprecedented amount of infrastructure so we can replace the current fossil fuel-dominated systems with cleaner solutions,” says Latimer. “Right now, many of the solutions we need are stalled out by a convoluted permitting and regulatory system that doesn’t prioritize clean infrastructure.”

Taff, CEO of geothermal energy provider Sage Geosystems, oversees her company’s work to connect what could be the world’s first geopressured geothermal storage to the electric grid, according to Time. In August, Sage announced a deal with Facebook owner Meta to produce 150 megawatts of geothermal energy for the tech company’s data centers.

Asked which climate solution, other than geothermal, deserves more attention or funding, Taff cites pumped storage hydropower.

“While lithium-ion batteries get a lot of the spotlight, pumped storage hydropower offers long-duration energy storage that can provide stability to the grid for days, not just hours,” Taff tells Time. “By storing excess energy during times of low demand and releasing it when renewables like solar and wind are not producing, it can play a critical role in balancing the intermittent nature of renewables. Investing in pumped storage hydropower infrastructure could be a game-changer in achieving a reliable, clean energy future.”

Rice University researchers pioneer climatetech breakthroughs in clean water nanotechnology

tapping in

Researchers at Rice University are making cleaner water through the use of nanotech.

Decades of research have culminated in the creation of the Water Technologies Entrepreneurship and Research (WaTER) Institute launched in January 2024 and its new Rice PFAS Alternatives and Remediation Center (R-PARC).

“Access to safe drinking water is a major limiting factor to human capacity, and providing access to clean water has the potential to save more lives than doctors,” Rice’s George R. Brown Professor of Civil and Environmental Engineering Pedro Alvarez says in a news release.

The WaTER Institute has made advancements in clean water technology research and applications established during a 10-year period of Nanotechnology Enabled Water Treatment (NEWT), which was funded by the National Science Foundation. R-PARC will use the institutional investments, which include an array of PFAS-dedicated advanced analytical equipment.

Alvarez currently serves as director of NEWT and the WaTER Institute. He’s joined by researchers that include Michael Wong, Rice’s Tina and Sunit Patel Professor in Molecular Nanotechnology, chair and professor of chemical and biomolecular engineering and leader of the WaTER Institute’s public health research thrust, and James Tour, Rice’s T.T. and W.F. Chao Professor of Chemistry and professor of materials science and nanoengineering.

“We are the leaders in water technologies using nano,” adds Wong. “Things that we’ve discovered within the NEWT Center, we’ve already started to realize will be great for real-world applications.”

The NEWT center plans to equip over 200 students to address water safety issues, and assist/launch startups.

“Across the world, we’re seeing more serious contamination by emerging chemical and biological pollutants, and climate change is exacerbating freshwater scarcity with more frequent droughts and uncertainty about water resources,” Alvarez said in a news release. “The Rice WaTER Institute is growing research and alliances in the water domain that were built by our NEWT Center.”

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This article originally ran on InnovationMap.