Advanced oxygen evolution catalysis: SnS2 and MoS2 decorated titania nanostructures in alkaline electrolytes

The development of non-noble metal electrocatalysts presents a promising pathway for efficient oxygen evolution during water splitting, attributed to their multi-component interactions, enhanced catalytic activity, and superior durability. In this study, we investigated the electrocatalytic oxygen evolution reaction (OER) using a ternary heterostructure electrocatalyst comprising TiO2 nanostructures coupled with SnS2 and MoS2 cocatalysts, synthesized via an ultrasonication-assisted process. Morphological analyses confirmed the successful deposition of SnS2 and MoS2 nanospecies onto the TiO2 nanostructures, resulting in a significant increase in the density of catalytically active sites and improved overall catalytic performance. X-ray photoelectron spectroscopy (XPS) further verified the formation of a well-defined ternary heterostructure. The optimized 10% SnS2/MoS2/TiO2 nanostructure exhibited exceptional OER performance, achieving a low overpotential of 271 mV at 10 mA cm-2 and a Tafel slope of 58 mV dec-1 in 1.0 M KOH. This performance surpasses that of both binary SnS2/MoS2 nanostructures and pristine TiO2. The superior catalytic activity is attributed to enhanced electrical conductivity, an increased number of active sites, and synergistic interactions between the three components. Additionally, a potential mechanism for charge transfer and carrier separation within the ternary heterostructure is proposed, offering insights into the observed enhancement in OER performance. These findings provide a solid foundation for the advancement and scalable application of these nanostructures in energy-related fields, paving the way for innovative solutions in sustainable energy generation.