An eco-friendly water decomposition tech developed at KAIST
A team of scientists at the Korea Advanced Institute of Science and Technology (KAIST) has developed an eco-friendly way to dissolve water into oxygen and hydrogen, the institute said.
Oh Il-kwon, a renowned mechanical engineering professor at KAIST, has led the research team. Oh highlighted that the new water decomposition technology uses nickel and cobalt instead of expensive jewelry catalysts such as platinum.
The new water decomposition catalyst “is easy to manufacture and can be mass-produced, and still its capability is comparable to the existing jewelry-based catalysts,” he said. “The research will contribute to commercialization of the original technology that can change water into chemical energy sources such as hydrogen.”
Oh studied aerospace engineering at Inha University in Incheon in the 1990s. He acquired his master’s degree in aerospace engineering at KAIST in 1997 and doctoral degree in mechanical engineering at the same institute in 2001.
Oh started working as a professor of mechanical engineering at KAIST in 2015. Before that, he was at LG Electronics between 2001 and 2004 and Stanford University between 2006 and 2007 as a visiting scholar.
The most widely used production process of hydrogen energy is to electrolyze water for decomposition. This process can produce pure hydrogen without negative environmental effects.
But its high cost has hindered its commercialization in industries. In particular, this process requires platinum and catalysts made of iridium and ruthenium oxide, which are highly expensive materials.
For this reason, researchers around the globe have pushed to develop less expensive catalyst materials.
According to Oh, the metallic compound catalyst made of nickel and cobalt is cheap but needs a higher electrical voltage, and thus has not been used in actual practice.
Oh and his team said they have tapped into a process called “hydrothermal synthesis,” which dissolves metallic materials in high-temperature liquid to synthesize materials.
They also applied a highly conductive carbon layer on the exterior of the nickel-cobalt catalyst to maximize electric charge transmission between electrodes and nano compounds.
Such processes have helped the new catalyst react with 30 percent lower electrical voltage and showed a 2.7 times higher catalyst activation rate, Oh said.
“Through multiple consecutive hydrothermal synthesis, we have succeeded in producing dual-layer nanocatalyst,” the research team said. “Even though it is much cheaper than the catalyst based on expensive jewelry materials, its performance does not fall behind.”
According to KAIST, the results of Oh and his team’s research has been published in the January edition of global science journal Advanced Energy Materials.