For decades, the promise of perovskite solar technology has lived in the gap between laboratory elegance and industrial reality — a gap defined not by physics, but by chemistry. A research team has now crossed that gap by redesigning the molecular intermediary at the heart of the manufacturing process, using a solvent whose relationship with lead iodide shifts with temperature: binding tightly in the cool, releasing cleanly in the heat. The result is a 100-square-centimeter solar module that achieves near-24-percent efficiency and endures months of extreme humidity — suggesting that the long-a