One-Pot Combustion Synthesis of S-Scheme Heterostructured CdS/CdMoO₄ Nanoparticles with Tightly Bound Interface for Enhanced Photocatalytic H₂O₂ Production

In this work, a series of CdS/CdMoO 4 samples were fabricated using a simple one-pot combustion method. The crystal structure, morphologies, chemical compositions, and optical properties were characterized through XRD, SEM, TEM, XPS, and UV–vis spectra. The photocatalytic test showed that CdS/CdMoO 4 composites had the best H 2 O 2 production performance, achieving a rate of 1394.71 μmol/g/h, which is approximately 2.5 times and 12 times higher than that of pure CdS and CdMoO 4, respectively. The significantly improved photocatalytic efficiency can be ascribed to the formation of an S-scheme heterojunction between CdS and CdMoO 4 . This heterojunction facilitates the efficient separation of charge carriers, thereby inducing high activity for H 2 O 2 formation. Active species trapping experiments revealed that holes (h + ) and superoxide radicals (·O 2 – ) were the primary active species involved in the photocatalytic process. Based on the energy band structures of the CdS/CdMoO 4 composites, a possible photocatalytic mechanism was proposed.