Project R-14696

Artificial leaves, nano-scale reactors on the road to green hydrogen and value-added chemicals through monolithic tandem-cells made from earth-abundant non-toxic elements. (Research)

Artificial leaves are nano-scale un-assisted solar-powered reactors and generate high-energy compounds; such as hydrogen, formate, glutamate, etc.; through solar-driven electrochemical reduction, and biocatalysis, of low-energy feedstocks, such as H2O or CO2. Absorption of solar energy is achieved by means of a suitable semiconductor (SC), such as silicon, hybrid organic inorganic perovskites, III-V, oxides, chalcogenides, etc. Tandem, or multijunction, devices allow unassisted and unbiased photoelectrochemical production of such desirable compounds. Combining a low-bandgap bottom SC with a high bandgap top SC optimizes the solar absorption and as such the solar-to-X efficiency. Computational studies suggest an optimum near the bandgap combination of 1.1 eV and 1.7-1.8 eV. In this study the Flemish and Korean collaborators aim to develop a monolithic artificial leaf utilizing a tandem of a silicon photoanode (Eg 1.15 eV) and a CuBi2O4 photocathode (Eg 1.85 eV). The tandem consists of earth-abundant, non-toxic, and highly chemically stable compounds which promise a long device lifetime and efficient green production of hydrogen, CO2 reduction, and value-added chemical production. The Shin group developed a highly thermally stable silicon photoelectrode utilizing a dual-purpose tunnel oxide passivating contact, or TOPCon layer. The Hardy group is expert on the wet-chemical synthesis of complex multifunctional (transition) metal oxides, including CuBi2O4 photocathodes.

01 January 2024 - 31 December 2025