Template-Directed Stepwise Growth of WS2 on Sr2SnO4: Interfacial Electronic Engineering for High-Performance Sensing and Energy Storage

The development of multifunctional materials capable of supporting both electrochemical sensing and energy-storage applications is important for integrated wearable and self-powered electronic technologies. In this work, WS2/Sr2SnO4 heterostructures with tunable WS2 loading were synthesized through a stepwise growth strategy using layered Sr2SnO4 as a structural template. The resulting heterostructures exhibit intimate interfacial coupling and loading-dependent structural organization. Their electrochemical properties were evaluated for serotonin sensing and lithium-ion storage. The high-WS2-loading heterostructure showed enhanced serotonin sensing performance and improved reversible lithium-storage behavior compared with the pristine components. Density functional theory calculations revealed interfacial electronic coupling and charge redistribution in the WS2/Sr2SnO4 heterostructure, while Li adsorption introduced additional states near the Fermi level that facilitate charge transport. These results demonstrate the potential of oxide-templated WS2 heterostructures as multifunctional platforms for electrochemical sensing and energy storage.