A team of Chinese researchers has developed a new self-supporting, 3D electrode that reduces overpotential, taking another step towards large-scale green hydrogen production.
Hydrogen energy development is keenly pursued by the world’s top minds as it is considered one of the least environmentally impactful energy sources available.
Green hydrogen, already an attractive energy source because it is so clean, also has an impressive calorific value – the amount of heat generated per consumed unit of hydrogen – making it a far more efficient energy source than liquid fuels like kerosene, and solid fuels like charcoal.
Typically, hydrogen is extracted and isolated through a method called water splitting. The relatively simple method involves breaking water down into its core components of oxygen and hydrogen, through a chemical reaction.
Interestingly, a type of water splitting occurs naturally in the process of photosynthesis. However, that process which is responsible for plants creating oxygen from carbon dioxide, water and sunlight, does not create hydrogen.
One of the fundamental challenges posed to scientists producing hydrogen from water splitting is identifying a catalyst that can efficiently increase both the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER), while reducing any overpotential. According to the online science publication Eurekalert.org, overpotential refers to non-ideal reactions during the HER and OER processes.
Working out of China’s Institute of High Energy Physics and the Ningbo Institute of Materials Technology and Engineering, the research team developed an electrode that can create a distinct reduction in overpotential during the water-splitting process.
Their work, published in the journal, Green Energy and Environment, outlines their method which involved creating honeycomb alloy from lanthanum, a rare earth element, and a nickel foam solution.
The resulting alloy is full of tiny, sub-micron-sized pores, much like honeycomb or very holey swiss cheese. The minute pores increase the surface area of the structure, resulting in a more significant electrochemical reaction, thereby increasing hydrogen production.
Professor Weiqun Shi, a scientist affiliated with the Institute of High Energy Physics, said that the team’s method can be scaled-up without much difficulty and that their recent breakthrough may show the way to mass-producing clean hydrogen effectively.
China remains the planet’s chief polluter but has also invested heavily in clean energy infrastructure and technologies, producing roughly 22 million tons of green hydrogen in 2019, about one-third of global production.