La-supported SnO-CaO composite catalysts for efficient malachite green degradation under UV-vis light.

This study presents the development and optimization of La@SnO-CaO composite catalysts for efficient photocatalytic degradation of malachite green dye in aqueous solutions under UV-vis light irradiation. The catalysts were prepared via conventional incipient-wetness impregnation and thoroughly characterized using advanced analytical techniques, including X-ray diffraction, Fourier transform infrared spectroscopy, UV-vis diffuse reflectance spectroscopy, N adsorption-desorption analysis, and scanning electron microscopy. To optimize photodegradation efficiency, the effects of three independent factors were systematically investigated using response surface methodology: Temperature, pH, and Sn/Ca molar ratio.