Biometabolically Derived Selenium Nanoparticles Armed with Protein Protective Suit toward High‐Performance Li‐Se Batteries

Abstract Selenium (Se) serves as a burgeoning high‐energy‐density cathode material in lithium‐ion batteries. However, the development of Se cathode is strictly limited by low Se utilization and inferior cycling stability arising from intrinsic volume expansion and notorious shuttle effect. Herein, a microbial metabolism strategy is developed to prepare “functional vesicle‐like” Se globules via Bacillus subtilis subsp . from selenite in sewage, in which Se nanoparticles are armed with a natural biological protein membrane with rich nitrogen and phosphorus, achieving the eco‐efficient conversion of trash into treasure (selenite, SeO 3 2− → Selenium, Se). The appealing‐design “functional vesicle‐like” Se globules are beneficial to accommodate volume changes of Se in electrochemical reactions, confining polyselenides via chemisorption, and enhancing mechanical strength of electrode by associated bacteria debris, realizing comprehensive utilization of microorganism. By conceptualizing “functional vesicle‐like” Se globules, rather than artificial Se‐host composites, as cathode for lithium–selenium batteries, it exhibits outstanding cycling stability and improved rate performance. This strategy opens the door to design smart electrode materials with unattainable structure that cannot be achieved by traditional approaches, achieving eco‐efficient conversion of pollutants into energy‐storage nanomaterials, which will be a promising research field for interdisciplinary of energy, biology, and environment.