Most of the hydrogen produced commercially is via steam reformation of natural gas. But there are other methods—notably H2 from H2O via hydrolysis. Yes, from water.
A new breakthrough at the KTH Royal Institute of Technology in Stockholm, Sweden, and published in Nature Communications, claims to be able to produce hydrogen from water efficiently inexpensively. It’s a potential answer to the hydrogen infrastructure problem, since cars could carry tanks of water that would be converted to hydrogen onboard. But we’ve had breakthroughs before.
The innovation of KTH Professor Licheng Sun and colleagues is to locate “water-splitting” catalysts that are not costly precious metals. The new material is a monolayer of nickel–vanadium-layered double hydroxide—and nickel and vanadium are not expensive. According to the Nature Communications authors, “[D]eveloping highly efficient catalysts to meet industrial requirements remains a challenge….Mechanistic studies indicate [the new material] can provide high intrinsic catalytic activity, mainly due to enhanced conductivity, facile electron transfer and abundant active sites. This work may expand the scope of cost-effective electrocatalysts for water splitting.”
Reports KTH, “If a cheap, stable and efficient way could be found to produce hydrogen from water, a hydrogen-fuel economy could finally become a reality.”
There’s certainly a lot of synergy, especially with renewable energy. According to Morry Markowitz, president of the Fuel Cell and Hydrogen Energy Association, “Fuel cells are capable of using hydrogen from a variety of sources and fuel cells are an ideal pairing with wind or solar power generation. Using wind or solar power to produce hydrogen via electrolysis minimizes the intermittencies inherent in those technologies. During periods when wind or sun are limited, fuel cells can use this renewably-produced hydrogen to produce clean, reliable, efficient power. This renewable hydrogen can also be used in fuel-cell vehicles.”
The promise is there, but the challenge is to translate and scale up lab breakthroughs into commercially viable processes. When it comes to extracting hydrogen from water, we’ve been down the road before.
- In 2014, scientists at the University of Glasgow in Scotland said they’d developed a hydrogen-from-water process that is not only safer and cheaper, but also “30 times faster.” That method also eschews precious metal catalysts. According to Professor Lee Cronin, “The process uses a liquid that allows the hydrogen to be locked up in a liquid-based inorganic fuel. By using a liquid sponge known as a redox mediator that can soak up electrons and acid we’ve been able to create a system where hydrogen can be produced in a separate chamber without any additional energy input after the electrolysis of water takes place. The link between the rate of water oxidation and hydrogen production has been overcome, allowing hydrogen to be released from the water 30 times faster…”
- In 2013, researchers at the University of Colorado, Boulder said they had developed “a new technique/system [that] could pave the way for the mainstream use of hydrogen as fuel,” reported CleanTechnica. The Colorado system uses a large solar-thermal system that concentrates the sun’s energy on a tall central tower, using mirror arrays. The towers reach 2,500 degrees, heating up metal oxides and releasing oxygen atoms that can (with the addition of steam as part of the process) allow oxygen from the water to collect on the metal oxide surface, allowing hydrogen gas to be harvested.
- In 2012, Caltech researchers claimed a “cheap and clean” method for hydrogen from water, again using cheap materials. Caltech Professor Mark Davis told MIT Technology Review that his process works at low temperatures, and doesn’t have any toxic byproducts. He starts with magnesium oxide, with a reaction created by “shuttling sodium ions in and out of it.” The MIT Technology Review account acknowledged that the technology “is probably far from being commercialized.” Davis said his team had been able to demonstrate that the same materials can be reused five times, but “if you were going to have one of these things work for real, you’d need to run it for thousands of cycles.”
It’s great that scientists are working overtime to make hydrogen from water work in the commercial arena. It’s impossible to pick a winner, but one of these processes may well strike gold—and lead to a low cost and environmentally friendly transportation solution.