Researchers at the Tel Aviv University (TAU) have developed a green hydrogen production method with over 90% efficiency using a biocatalyst, according to H2 View.
Developed by TAU doctoral student Itzhak Grinberg and Dr. Oren Ben-Zvi, with guidance from Prof. Iftach Yocaby and Prof. Lihi Adler-Abramovich, the research results have been published in the Carbon Energy journal.
Grinberg explained that although atmospheric hydrogen is produced by enzymes in microscopic organisms which receive energy through photosynthesis, it remains very rare. In theory, the team wanted to electrify the enzymes to provide energy rather than the sun.
“The result is a particularly efficient process, with no demand for extreme conditions, that can utilise electricity from renewable sources such as solar panels or wind turbines,” Grinberg said. “However, the enzyme ‘runs away’ from the electric charge, so it needs to be held in place through chemical treatment. We found a simple and efficient way to attach the enzyme to the electrode and utilise it.”
Using a hydrogel to attach an enzyme to the electrode, the researchers were able to produce green hydrogen using a biocatalyst with over 90% efficiency, which the team has described as a “ground-breaking milestone.”
Prof. Yacoby, said, “The material of the gel itself is known, but our innovation is to use it to produce hydrogen. We soaked the electrode in the gel, which contained an enzyme for producing hydrogen, called hydrogenase.”
Able to hold the enzyme for extended periods, including under electric voltage, Yacoby said the gel makes it possible to produce hydrogen with “great efficiency and at environmental conditions favourable to enzyme – for example, in salt water, in contrast to electrolysis, which requires distilled water.”
Another advantage of the gel, according to Prof. Adler-Abramovich, is that the gel “assembles itself.”
“You put the material in water, and it settles into nanometric fibres that form the gel,” Adler-Abramovich, said. “We demonstrated that these fibres are also able to stick the enzyme to the electrode. We tested the gel with two other enzymes, in addition to the hydrogenase, and proved it was able to attach different enzymes to electrode.”
The research team is hopeful that the breakthrough could enable the low-cost commercial production of green hydrogen.
Dr. Ben-Zvi, said, “We hope that in the future, it will be possible to employ our method commercially, to lower the costs, and to make the switch towards using green hydrogen in industry, agriculture, and as a clean energy source.”