HYDROSOL-PLANT: Structured Redox Reactors for H2 Production from Solar Thermochemical H2O Splitting

The "holy grail" of solar chemistry and solar engineering, is the technical storage of solar energy into a more easily transformable and transportable form, namely an energy carrier such as H-2. The two-step redox-based solar thermochemical H2O splitting cycle is considered to be among the most promising approaches for the production of H-2 from entirely renewable sources (solar energy and water). In this redox cycle an active material is initially reduced thermally under inert atmosphere and at the next step it is oxidized from H2O producing H-2. The materials that have been in the core of solar chemistry research are metal oxides such as ferrites, cerium oxides, perovskites, etc. The reactor types that are being investigated for the redox thermochemical splitting of H2O are either powder-particle reactors or structured reactors. In the current work Ni-ferrite and Ce-oxide structured into different monolithic bodies (honeycombs, foams) were evaluated w.r.t. their redox activity. Based on this investigation, the most promising structure was further scaled-up for the construction of the full-scale reactors of the HYDROSOL-PLANT solar plant installation.