Scalable Solution Synthesis and Photocatalytic Activity of Layered ZnO and MoS₂ Heterostructures

Numerous inorganic materials have been identified as potential candidates for high-performance photocatalysts. However, their solar-to-energy conversion efficiencies still fail to meet commercial requirements. The main hurdle is the rapid recombination of photoexcited electrons and holes in single-phase materials. A viable predicted approach to suppress charge recombination is coupling two materials to form a two-dimensional (2D) heterostructure that physically separates photoinduced electrons and holes in different layers. In this work, the heterostructure-based paradigm was tested and a scalable solution synthesis of epitaxial ZnO-MoS₂ heterostructure was developed. A 2D ZnO-MoS₂ heterostructure was synthesized under hydrothermal conditions by stabilizing intermediate Zn-hydroxide states on a functionalized MoS₂ surface. Detailed characterization showed the formation of multilayer heterostructure with MoS₂ flakes intercalated between large size ZnO plates. The performance of this heterostructure was evaluated using photocatalytic degradation of rhodamine B. A degradation efficiency of 70‰ was measured within 90 minutes of visible light irradiation, almost doubling the efficiency of the corresponding single-phase materials or their physical mixtures.