Mild and Effective Decatungstate-Catalyzed Degradation of Methyl Orange Under Visible Light

Decatungstate (DT) is a highly promising photocatalyst for dioxygen (O2)-based reactions but has hardly been applied in the photocatalytic degradation technology of dye. Here, we synthesized hydrophilic DT–SO3H salts by incorporating tetra-alkyl cations with sulfonic acid groups, aiming to enhance both the water solubility and catalytic efficiency of DT under visible light. Comprehensive characterization of DT–SO3H using ultraviolet–visible spectroscopy (UV–Vis), Fourier Transform Infrared Spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), Photocurrent (PTC), and Electrochemical Impedance Spectroscopy (EIS) confirmed its improved properties. DT–SO3H demonstrated outstanding photocatalytic performance, achieving 90% degradation of methyl orange within 25 min under continuous visible light irradiation. This study presents a cost-effective and efficient method for degrading methyl orange, representing a significant advancement in the development of high-performance photocatalysts and opening new avenues for the study and application of photocatalytic dye degradation technologies.