A research team at Tohoku University's Advanced Institute for Materials Research has developed a new method to accelerate the discovery of affordable and stable materials for hydrogen production. The process involves water splitting, with two key reactions: the oxygen evolution reaction (OER) and the hydrogen evolution reaction (HER). While some metal oxides have shown potential as low-cost catalysts, they often degrade in acidic environments used for industrial water splitting. The team's closed-loop research framework involves stages of catalyst development, including data analysis, real operating condition testing, and lab experiments, all connected through a digital system. The core of their work is a data-driven platform called DigCat, enabling efficient exploration of a wide range of materials by predicting their behavior during water splitting. By using this approach, they identified RbSbWO₆ as a promising catalyst that remained structurally stable even after extended use. This compound showed strong performance for both OER and HER in acidic conditions, a rare feat for low-cost metal oxides. The team's framework can also be adapted to other important chemical reactions beyond water splitting, such as CO2 conversion and ammonia production. The next phase involves expanding the surface-state database and applying the method to different material systems to accelerate progress in affordable and efficient solutions for the global energy transition.