MoS2/SrTiO3-x perovskite heterostructure: Fabrication, characterization, and comprehensive photodegradation study towards Rhodamine B
Mahdieh Rezaei, Ali A. Ensafi, Esmaeil Heydari‐Bafrooei
Abstract
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 SrTiO 3 nanocubes, recognized as a prominent representative of the ABO 3 perovskite family, modified by MoS 2 nanoflowers was prepared through a simple two-step hydrothermal method . After introducing oxygen vacancies, the bandgap of SrTiO 3 reduced from 3.2 to 2.9 eV. The Z-scheme MoS 2 /SrTiO 3-x composite shows increased photocatalytic efficiency for oxygen evolution and RhB degradation reactions. Under optimal conditions, the photodegradation rate of MoS 2 /SrTiO 3-x heterostructure is about 8 times higher than that of pure SrTiO 3 . Also, the MoS 2 /SrTiO 3-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 SrTiO 3 nanocubes. The enhanced performance may be due to the interfacial transfer of photogenerated electrons from SrTiO 3 to MoS 2 , 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 • OH and • O 2 − , 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.