Scientists of Tomsk Polytechnic University jointly with teams from the University of Chemistry and Technology, Prague and Jan Evangelista Purkyne University in Ústí nad Labem have developed a new 2D material to produce hydrogen, which is the basis of alternative energy. The material efficiently generates hydrogen molecules from fresh, salt, and polluted water by exposure to sunlight.
The developed material is a three-layer structure with a 1-micrometer thickness. The lower layer is a thin film of gold, the second one is made of 10-nanometer platinum, and the third is a film of metal-organic frameworks of chromium compounds and organic molecules.
“During the experiments, we watered material and sealed the container to take periodic gas samples to determine the amount of hydrogen. Infrared light caused the excitation of plasmon resonance on the sample surface. Hot electrons generated on the gold film were transferred to the platinum layer. These electrons initiated the reduction of protons at the interface with the organic layer. If electrons reach the catalytic centers of metal-organic frameworks, the latter were also used to reduce protons and obtain hydrogen,” Olga Guselnikova, one of the authors and a researcher of the TPU Research School of Chemistry & Applied Biomedical Sciences, explains.
Experiments have demonstrated that 100 square centimeters of the material can generate 0.5 liters of hydrogen in an hour. It is one of the highest rates recorded for 2D materials.
“In this case, the metal-organic frame also acted as a filter. It filtered impurities and passed already purified water without impurities to the metal layer. It is very important, because, although there is a lot of water on Earth, its main volume is either salt or polluted water. Thereby, we should be ready to work with this kind of water,” Olga notes.
