A place for charges to rest: Oxford finds a way to cut solar's energy losses by about 75%

Every solar cell fights the same quiet battle: light frees electrical charges, and if they recombine too quickly, their energy is lost as waste. University of Oxford researchers studying bismuth sulfide — a familiar, abundant semiconductor — found it cheats that battle. The material soaks up light strongly through one set of energy levels, while a second set just below acts like a waiting room, holding charges safely so they live longer. At room temperature, the team measured a charge-loss rate roughly 75% lower than in comparable strong absorbers. It is not a finished panel — the study, published in Nature, identifies the mechanism — but it hands solar designers a new feature to hunt for in other materials too.

SDG 9 · Industry, innovation and infrastructure — Mechanism: tech innovation