Non-van der Waals Layered Molybdenum Sulfide Wires with Perpendicular Layer Stacking and Tunable Interlayer Domains

Abstract

A quasi-layered (NH4)nMoSx<middle dot>delta H2O wire structure is developed via solution-based precipitation under ambient conditions. The resulting material exhibits longitudinal stacking alignment and periodically exposed interlayer regions, stabilized by ammonium and water species. In contrast to conventional van der Waals layered systems, the synthesized structure maintains crystallographic coherence while enabling reversible interlayer modulation, as confirmed by X-ray diffraction and thermal analysis. This structural adaptability enables dynamic control of spacing without disrupting the framework, offering new possibilities for ion-accessible architectures. Mercury ion adsorption is employed as a model system to evaluate the functionality of engineered architecture. The wire exhibited high uptake capacity, fast adsorption kinetics, and a distinct interlayer expansion upon binding, underscoring the role of structural design in performance. This study establishes a framework for constructing non-van der Waals layered materials with tunable interlayer chemistry and accessible pathways, suitable for ion transport, molecular intercalation, and related applications.