May 12, 2021


Imagine a world in which cars, trucks, jets and even rockets would run on clean hydrogen, emitting only water vapor as a waste product, replacing fossil fuels like polluting gasoline that release greenhouse gasses into the atmosphere.

Not only would the human environment be cleaned up, but the world would no longer be dependent on oil produced in the Arab world, thus minimizing the hatred for Israel.

Opponents of using hydrogen for transportation have claimed that it would take “decades” to overcome the technical and economic problems of implementing wide-scale use of the gas and that focusing on the use of the hydrogen for vehicles is a “dangerous detour” from more readily available solutions to reducing the use of fossil fuels in vehicles.

A decade ago, Wired News reported that “experts say it will be 40 years or more before hydrogen has any meaningful impact on gasoline consumption or global warming, and we can’t afford to wait that long. In the meantime, fuel cells are diverting resources from more immediate solutions.”

But now, Israeli scientists have achieved a very important step in realizing the dream. Researchers at Ben-Gurion University of the Negev in Beersheba and at the Technion-Israel Institute of Technology in Haifa have made a discovery – described as a “milestone” – in efforts to develop new ways to make hydrogen fuel from water. This “water splitting” idea has just been published in the prestigious scientific journal Nature Communications.

Researchers led by Dr. Arik Yochelis and Dr. Iris Visoly-Fisher of BGU and Prof. Avner Rothschild of the Technion, have cracked the chemical mechanism that occurs during the photochemical splitting of hydrogen peroxide (H2O2) over iron-oxide photo-electrodes.

The researchers say that although it has been well-known for decades that production of hydrogen that does not emit greenhouse gases requires the splitting of water molecules (H2O) into the elements from which they are composed (two hydrogen atoms and one oxygen atom), that process has always demanded more energy than was gained back at the end it. As a result, it has never been practical on a commercial basis.

The discovery, they maintain, could have a significant impact on efforts to replace carbon-based fuels with more environmentally friendly hydrogen fuels. Car manufacturers are eager to develop efficient, environmentally friendly hydrogen-powered vehicles that, unlike electric vehicles, allow for fast refueling and extended mileage.

To conquer the challenge, the researchers were the first team to successfully reveal the fundamental chemical reaction present in the power of the sun’s rays that could form the missing link to generate the electricity necessary to accomplish this process. This would allow a natural unfolding, instead of relying on large amounts of man-made energy sources or precious metals to catalyze the reaction.

After years of challenging experiments during which Rothschild’s laboratory was unable to overcome the barrier in efficiency, he approached Drs. Yochelis and Visoly-Fisher to collaborate in the attempt to understand the missing piece of the puzzle.

“Beyond the scientific breakthrough, we have shown that the photo-electrochemical reaction mechanism belongs to a family of chemical reactions for which Prof. Gerhard Ertl was awarded with Nobel Prize in Chemistry about a decade ago. Our discovery opens new strategies for photochemical processes,” said Yochelis, who works at BGU’s Blaustein Institutes for Desert Research and the Alexandre Yersin Department of Solar Energy and Environmental Physics. “Photo-electrochemical water splitting is an elegant route to store radiant solar power in chemical bonds by producing hydrogen,” they wrote in their paper.

Hydrogen does not come as a pre-existing source of energy like fossil fuels; it is first produced and then stored as a carrier, much like a battery. However, today, the vast majority of hydrogen is made from methane, which is the major component of natural gas. Hydrogen can be produced using renewable sources, such as from the wind or breaking down water, but it is a highly expensive process.

If hydrogen is made from petroleum, the process itself produces greenhouse gasses that choke our environment. Hydrogen production using renewable energy resources would not create such emissions, but the scale of renewable energy production would need to be expanded to be used in producing hydrogen for a significant part of transportation needs.

There are three brands of automobiles that run on hydrogen – the Toyota Mirai, the Hyundai ix35 FCEV and the Honda Clarity. But they are extremely expensive and hydrogen fuel for them is not readily available. Trains, forklifts, bicycles, cargo bikes, canal boats, golf cartsmotorcycleswheelchairsshipssubmarines and rockets have been developed to run on hydrogen as well. NASA even used hydrogen to launch space shuttles into space.

But the problems of supplying hydrogen at low cost has slowed its application. In 2013, The New York Times reported that there were only 10 publicly accessible hydrogen-filling stations in the US, eight of which are in Southern California.

The US government has been on the record for 15 years as being in favor of hydrogen. In 2003, George W. Bush announced an initiative to promote hydrogen-powered vehicles; in 2014 the Obama administration said it favored the speeding up of production and development of hydrogen-powered vehicles.

The study, which was funded jointly by research grants from Israel’s Ministry of National Infrastructures, Energy and Water and the Ministry of Science and Technology can now help the world push ahead to efficient hydrogen use.