Application of 2D Transition Metal Sulfides in Energy Storage

The emergence of metallic phase two-dimensional molybdenum disulfide (MoS2) introduces a new class of materials boasting superior electrical conductivity and catalytic activity. This presentation aims to provide a comprehensive review of the atomic structures and electrochemistry of metallic MoS2, an essential element in an array of established and burgeoning technological applications, with detailed studies of our lab in hydrogen evolution reaction, lithium ion and sodium ion batteries, supercapacitor, and all solid state Li sulfur batteries.<br/>For example, recently, in our lab, a highly conductive carbon fiber decorated with hybrid 1T/2H MoS2 nanosheets is designed. The high chemical and electrochemical compatibility among MoS2 and sulfide solid state electrolyte can greatly improve the stability of the cathode and therefore maintain pristine interfaces. The uniform distribution of electrical conductive metallic 1T MoS2 on carbon fiber benefits the electron transfer between carbon and sulfur. Meanwhile, the layered structure of MoS2 can be intercalated by a large amount of Li ions facilitating ionic and electronic conductivity. In consequence, the charge transfer and reaction kinetics are greatly enhanced, and the decomposition of SSEs is successfully relieved. As a result, the all solid state lithium sulfur delivers an ultrahigh initial discharge and charge capacity of 1456 and 1470 mAh g−1 at 0.05 C individually with ultrahigh coulombic efficiency and maintains high capacity retention of 78% after 220 cycles. The batteries also obtain a remarkable rate performance of 1069 mAh g−1 at 1 C.<br/>This talk will span the exploration of the atomic and band structures of metallic MoS2, its electrical and optical properties, fabrication methodologies, and prominent emergent applications in the realm of electrochemical energy storage and conversion. A central feature of the talk will be the intricate relationship between the atomic structure, properties, and performance of metallic MoS2, emphasizing the critical importance of understanding these fundamentals for emerging energy applications.