An Efficient Biphase MoO₃/Zro₂ Catalyst for Visible Light‐Driven Photocatalytic Degradation of Methylene Blue: Reusability and Detoxicity Assessment

Synthesis of a biphase MoO 3 /ZrO 2 nanocomposite (NC) is achieved using a wet‐chemical hydrothermal method. The morphology, phase, and structure of MoO 3 /ZrO 2 NC are analyzed using X‐ray diffraction and field‐emission scanning electron microscope techniques. The hydrodynamic particle size is 213 nm, and Fourier‐transform infrared analysis reveals the formation of Mo–O–Mo and Zr–O bonds. The elemental valence states and binding energy details are determined using X‐ray photoelectron spectroscopy. Photoluminescence spectroscopy is employed to evaluate the recombination behavior of photogenerated electron–hole pairs, confirming reduced recombination in the heterojunction structure. Electron spin resonance analysis further confirms the presence of oxygen vacancies in the MoO 3 /ZrO 2 NC. The photocatalytic activity of MoO 3 /ZrO 2 NC is tested by reducing methylene blue (MB) dye molecules under visible light irradiation. The photocatalytic efficiency is further tested by varying the catalyst dosage and pH of the dye. The MoO 3 /ZrO 2 NC photocatalyst demonstrates superior performance with a percentage degradation efficiency of 86% at 60 mg/L and follows a type II staggered heterojunction. It also maintains significant stability across multiple cycles, indicating its potential for repeated use. The role of scavengers in the photocatalytic degradation of the MB dye is also investigated. Seed germination tests show a 98.4% germination rate in 7 h, confirming effective detoxification and potential plant growth enhancement.