Thiocyanate Coordination Regulates the Interlayer Ammonium Ion Storage Structure of Molybdenum Disulfide

Aqueous ammonium ion storage utilizes the intercalation and coordination diffusion mechanisms of NH4+ within the host material, resulting in a low-cost, high-safety energy storage device. However, the capacity of the NH4+ storage hosts, represented by layered materials, is mainly limited by the limited interlayer size and coordination sites. Here, a strategy is proposed to enhance NH4+ storage by utilizing nonmetallic ions with long-chain structures to regulate the interlayer spacing and coordination activity of MoS2. Atomic-level electron microscopy, chemical reactions, and theoretical simulations revealed that SCN– was successfully intercalated into MoS2 and coordinated with S atoms to construct an interlayer network. The intercalation of SCN– provides sufficient space and abundant hydrogen-bonding sites. This work effectively solves the dilemma of traditional layered materials in NH4+ storage and demonstrates the broad prospects of interlayer coordination engineering strategies for energy storage devices.