Facile sonochemical route to sponge-like porous AgCl/malachite for enhanced photocatalytic performance and stability

Abstract

Addressing the persistent challenges of photochemical corrosion and poor stability in silver-based photocatalysts, this study proposes a sonochemical synthesis strategy to construct sponge-like porous AgCl/Malachite heterojunction composites. The as-prepared material exhibits outstanding photocatalytic activity and cycling stability toward methyl orange (MO). Under light irradiation, the composite achieves a degradation efficiency of 92.8% within 30 min, with a reaction rate constant of 0.08352 min⁻¹, which is 39.4 times higher than that of pure Malachite and 1.9 times greater than pure AgCl. Importantly, the photocatalytic performance shows no significant degradation after five consecutive cycles. The enhanced performance is attributed to the following factors: the formed heterojunction between AgCl and Malachite effectively promotes the separation and transfer of photogenerated charge carriers. The hierarchical porous structure and high specific surface area optimize mass transfer during the reaction and provide abundant active sites. Moreover, the composite architecture significantly suppresses the photochemical corrosion of AgCl. This work not only offers a new approach to mitigating the photochemical corrosion of silver-based materials for developing highly efficient and stable photocatalysts, but also provides a fast and controllable sonochemical route for the scalable synthesis of functional heterojunction materials with potential for industrial production.