There are easier ways to split water

Chuan Zhao of the U of New South Wales Splitting water for energy is clearly the hot new thing.

Just a few days ago, Paul C. W. Chu of the University of Houston, and founding director of the Texas Center for Superconductivity at UH, and others came up with a cheap catalyst for the job: ferrous metaphosphate grown on a conductive nickel foam platform.

This is a remarkable improvement on the usual expensive electrocatalysts used – iridium, platinum or ruthenium – and a welcome respite in a world thirsting for more energy options.

Now, down under, Chuan Zhao and others at the University of New South Wales have come up with “ultrathin slices of porous metal-organic complex materials coated onto a foam [nickel] electrode, which the researchers have unexpectedly shown is highly conductive of electricity and active for splitting water.” OK, we’re quoting the press release verbatim there.

“Splitting water usually requires two different catalysts, but our catalyst can drive both of the reactions required to separate water into its two constituents, oxygen and hydrogen,” Zhao was quoted as saying in the same release. The reaction that results in the release of hydrogen relies on one electrode; that for the evolution of oxygen another.

Metal-organic framework

Zhao’s team deposited the organic material (that’s 2,6-naphthalenedicarboxylic acid dipotassium for those with academic OCD) into a solution of nickel acetate and iron nitrate.

“Compared to other water-splitting electrocatalysts reported to date, our catalyst is also among the most efficient,” Zhao says. Perhaps Chu out at UH should weigh in here.

Still, both teams relied on increase area of contact between their electrocatalysts and the water. And each came up with a solution that is cheaper and longer-lasting than those in standard use.

Zhao’s research appeared in Nature Communications; Chu’s in the Proceedings of the National Academy of Sciences.