Plasmonic enhanced branched Ag sensitized Cu2O-CuO/TiO2 heterojunction with unprecedented photocatalytic degradation under visible light

A novel plasmonic Ag assisted Cu2O-CuO/TiO2 heterojunction photocatalyst was prepared using a facile sol-gel technique, and its MB degradation efficiency was explored. The physicochemical, morphostructural, and spec-troscopic analyses using XRD, UV-vis-DRS, SEM, TEM, Raman, ESR, PL and XPS showed the formation of Ag@Cu2O-CuO/TiO2 hybrid photocatalyst, exhibiting surface plasmon resonance (SPR) and interfacial ternary heterojunctions. The SPR exhibited by the bulbous branched Ag nanostructures resulted in broad visible light absorption that extended into the near-infrared region. This plasmonic-heterojunction hybrid photocatalyst has shown excellent photocatalytic degradation, far surpassing the performance of its pristine counterparts under visible light illumination. The improved photocatalytic degradation of MB is attributable to the synergistic impact of reduced electron-hole pair recombination owing to Cu2O-CuO/TiO2 ternary junction, broad visible light absorption and near-field enhancement through the surface plasmon resonance effect. The current study demonstrates an integrated plasmonic-heterojunction photocatalytic system that offers a promising avenue for enhancing photocatalytic performance in dye-contaminated water treatment.