MoS2/SrTiO3-x perovskite heterostructure: Fabrication, characterization, and comprehensive photodegradation study towards Rhodamine B

Photocatalytic water splitting and photodegradation of pollutants offer promising solutions for addressing the energy crisis and improving water treatment processes. In this work, oxygen vacancy-mediated SrTiO3 nanocubes, recognized as a prominent representative of the ABO3 perovskite family, modified by MoS2 nanoflowers was prepared through a simple two-step hydrothermal method. After introducing oxygen vacancies, the bandgap of SrTiO3 reduced from 3.2 to 2.9 eV. The Z-scheme MoS2/SrTiO3-x composite shows increased photocatalytic efficiency for oxygen evolution and RhB degradation reactions. Under optimal conditions, the photodegradation rate of MoS2/SrTiO3-x heterostructure is about 8 times higher than that of pure SrTiO3. Also, the MoS2/SrTiO3-x heterojunction exhibits improved broadband light absorption, leading to photocurrent densities of 0.52 mA cm-2 at 1.23 V vs. RHE. This represents a five-fold increase in photocurrent compared to pure SrTiO3 nanocubes. The enhanced performance may be due to the interfacial transfer of photogenerated electrons from SrTiO3 to MoS2, leading to effective charge separation in the photocatalyst. The Langmuir-Hinshelwood model was used to model the kinetic and equilibrium data. Photocatalysis is greatly influenced by center dot OH and center dot O2-, as demonstrated by experiments involving reactive species trapping. Using the Z-scheme mechanism and oxygen vacancy engineering for photocatalysis, this work presents a new idea for developing efficient materials.