AgPO-Deposited TiO@TiC Petals for Highly Efficient Photodecomposition of Various Organic Dyes under Solar Light.

Two-dimensional TiC MXenes can be used to fabricate hierarchical TiO nanostructures that are potential photocatalysts. In this study, the photodecomposition of organic dyes under solar light was investigated using flower-like TiO@TiC, deposited using narrow bandgap AgPO. The surface morphology, crystalline structure, surface states, and optical bandgap properties were determined using scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), nitrogen adsorption analysis, and UV-Vis diffuse reflectance spectroscopy (UV-DRS). Overall, AgPO-deposited TiO@TiC, referred to as AgPO/TiO@TiC, demonstrated the best photocatalytic performance among the as-prepared samples, including TiO@TiC, pristine AgPO, and AgPO/TiO P25. Organic dyes, such as rhodamine B (RhB), methylene blue (MB), crystal violet (CV), and methylene orange (MO), were efficiently degraded by AgPO/TiO@TiC. The significant enhancement of photocatalysis by solar light irradiation was attributed to the efficient deposition of AgPO nanoparticles on flower-like TiO@TiC with the efficient separation of photogenerated e-/h+ pairs, high surface area, and extended visible-light absorption. Additionally, the small size of AgPO deposition (ca. 4-10 nm diameter) reduces the distance between the core and the surface of the composite, which inhibits the recombination of photogenerated charge carriers. Free radical trapping tests were performed, and a photocatalytic mechanism was proposed to explain the synergistic photocatalysis of AgPO/TiO@TiC under solar light.