A team from the University of Toronto has developed a new catalyst that could be used in clean energy technologies that rely on producing hydrogen from water.
Hydrogen is a key ingredient in several applications, including fuel and fertilizers. For energy storage, renewable electricity could produce hydrogen from water and later reverse the process in an electrochemical fuel cell to produce clean power on demand.
“Hydrogen is a hugely important industrial feedstock, but unfortunately today it is derived overwhelmingly from fossil fuels, resulting in a large carbon footprint,” professor Ted Sargent, senior author on the new study, said in a statement. “Electrolysis – water splitting to produce renewable hydrogen and oxygen – is a compelling technology, but it needs further improvements in efficiency, cost, and longevity. This work offers a fresh strategy to pursue these critically important aims.”
There has been a push in the science community to develop catalysts that reduce the amount of electricity needed to split water into hydrogen and oxygen, without using expensive metals like platinum or operate under acidic conditions.
“Our new catalyst is made from copper, nickel and chromium, which are all more abundant and less costly than platinum,” Cao-Thang Dinh, a co-lead author on the paper along with his fellow postdoctoral researchers Pelayo Garcia De Arquer and Ankit Jain, said in a statement. “But what’s most exciting is that it performs well under pH-neutral conditions, which opens up a number of possibilities.”
The most abundant source of water on Earth is seawater, but using seawater with traditional catalysts under acidic conditions require the salt to be removed first in an energy-intensive process. However, researchers can avoid the high costs of desalination by operating at neutral pH, which could also enable the use of microorganisms to make chemicals like methanol and ethanol.
“There are bacteria that can combine hydrogen and CO2 to make hydrocarbon fuels,” Garcia De Arquer said. “They could grow in the same water and take up the hydrogen as it’s being made, but they cannot survive under acidic conditions.”
Using renewable energy to convert waste CO2 into fuels or other value-added products is the goal of the NRG COSIA Carbon XPrize. A team from Sargent’s lab is among the five finalists in the international competition, vying for the US $7.5-million grand prize.
The study was published in Nature Energy.
