Ultrafast Joule Heating Processing of Lunar Soil Minerals for Water Electrolysis

Maximizing the utilization of in situ extraterrestrial resources, including solar-powered water electrolysis using lunar soil as a catalyst, is a promising strategy for achieving a sustainable fuel and oxygen supply for lunar exploration. However, these lunar soil-based silicate minerals suffer from unsatisfactory intrinsic activity for water splitting due to poor electrical conductivity and the lack of catalytic sites. Here we report the use of a simple Joule-heating method to sinter the minerals into a disordered matrix at ∼2000 °C. The as-prepared amorphous minerals can significantly reduce the overpotential and exhibit good stability (>150 h) due to enhanced charge transport kinetics and intrinsic activity. We further demonstrate the solar-driven water electrolysis stack using sintered lunar soil simulants as catalysts, showing the practicality of such a system. This work provides insights into in situ resource utilization of lunar soils by engineering crystalline structures and electronic configurations by using an ultrafast Joule-heating method.