Metal oxide- and metal-loaded mesoporous carbon for practical high-performance Li-ion battery anodes

The rapidly expanding Li-ion battery market needs new materials that can satisfy the increasing energy storage demand. Metal oxides and some metals such as tin are viable alternatives to graphite as Li-ion battery anodes, but their low conductivity and large volume change during cycling impose severe challenges that need to be overcome. Confinement of metal oxide and metal nanomaterials within mesoporous carbon (MC) is an effective strategy in this regard, but complex synthesis and nanoparticle aggregation have hindered its application. Herein, we report a facile, scalable and generalized methodology for the room-temperature synthesis of metal oxide and metal nanoparticles within a MC host. The approach has been successfully applied to achieve uniform distribution and prevent aggregation of a large variety of metal oxide and metal nanomaterials in MC support. These nanocomposites were screened as Li-ion battery anodes, and the optimal candidates were shown to be superior to previously reported systems. Our synthesis method was scaled up using commercial MC. The nanocomposites were validated in a high-loading electrode (4 mg/cm2) with a practical voltage range (< 2 V vs. Li+/Li), impressive initial Coulombic efficiency (> 100%), and excellent stability (~ 500 mAh/g after 250 cycles at 0.2 A/g), which was 1.5–2x better than commercial graphite at the same testing conditions. The facile nature, universality and versatility of our approach make it possible to load various metal oxide and metal nanomaterials within different types of MC. These nanocomposites would be of significant interest to different fields, such as energy storage and conversion, sensing, and catalysis.