A team from the Institute of Chemical Technology (ITQ-CSIC-UPV), a joint center of the Spanish National Research Council (CSIC) and the Polytechnic University of Valencia (UPV), along with the Institute of Information and Communication Technologies (ITACA) at UPV, has developed materials that improve the process of obtaining hydrogen from water using microwave radiation. This process allows for the production of hydrogen from renewable electrical energy, thereby preventing CO2 emissions associated with hydrogen production.
The research, published in the journal Advanced Energy Materials, focuses on improving green hydrogen production through redox cycles, where the material absorbs and releases oxygen from water, separating it from oxygen in a stable manner. The process developed by the CSIC research team, under the Ministry of Science, Innovation, and Universities of Spain (MICIU), and UPV allows for the production of green hydrogen from renewable electrical energy due to the design and use of materials with these redox properties that respond to microwave radiation. The basis of the redox chemical cycle is the transfer of electrons between atoms of different elements in the presence of an induced electromagnetic field, enabling the electrification of the process.
Microwaves offer unique advantages in the electrification of a redox process, such as providing electrical energy without the need for contacts and drastically reducing the cycle's temperature (from 1,300 °C to 400 °C), which also reduces the complexity of the H2 production process and maximizes energy efficiency.
Material Properties
The main novelty of the work is the exhaustive study of the material properties that determine the process performance. The foundation has been laid for the design of materials to adapt the production of oxygen and hydrogen and adjust the material's energized state based on the desired application. Additionally, it has been demonstrated that it is possible to extract oxygen through a highly rapid and controlled pulsed process.
“The design of the cavities or chambers where we apply microwaves, as well as the control of the radiation process on these materials, is fundamental to leveraging the unique advantages offered by microwave technology. In recent years, this technology has been consolidated in numerous industrial applications due to its rapid scalability and high energy efficiency,” explains Jose Manuel Catalá, director of ITACA.
The study has shown that the materials designed and used to improve hydrogen production are resistant and stable. “During the research, a detailed study was conducted on the influence of different dopants introduced into the matrix material (cerium oxide) on hydrogen production, with the aim of adjusting the interaction with microwave radiation and the properties of the resulting energized material. Subsequently, the hydrogen production capacity of this material and the mechanism governing the process were studied, which will facilitate future material design,” notes José Manuel Serra, director of ITQ.
The project has been funded by the Ministry of Science, Innovation, and Universities through European Next Generation EU funds and Ramón y Cajal contracts, and by the Regional Government of Valencia.
