China's solar-powered 'biohybrids' remove 94% uranium from wastewater

Chinese scientists at Southwest University of Science and Technology have developed an innovative “self-regenerating bacteria-mineral biohybrid system” that significantly improves the cleanup of uranium-contaminated wastewater. This system harnesses light-harvesting nanoparticles grown in situ on the surface of Shewanella putrefaciens bacteria, creating a tightly integrated biohybrid that functions like a solar cell. When exposed to light, the ferrous sulfide nanoparticles generate photoelectrons that accelerate electron transfer, enabling the bacteria to convert soluble uranium into a stable, immobile precipitate. This process achieves a remarkable 94% uranium removal rate in actual mine wastewater, compared to the 48% removal rate by conventional bacteria. The biohybrid system operates as a closed-loop, self-renewing cycle where photoelectrons enhance bacterial metabolism, which in turn regenerates the mineral active sites, maintaining continuous treatment efficiency. Beyond uranium removal, the treated water exhibited reduced toxicity to crops, indicating ecological benefits. This technology addresses