Efficient charge separation in Ag nanoparticles functionalized ZnO nanoflakes/CuO nanoflowers hybrids for improved photocatalytic and SERS activity

Plasmonic semiconductor nanohybrids have generated the new advancement in the field of photocatalysis and SERS based sensing by their outstanding remediation and sensing capability towards the toxic organic pollutant that exists in the environment. We have synthesized Ag nanoparticles functionalized ZnO-CuO nanohybrids by the combined approach of hydrothermal and chemical reduction methods. TEM, FESEM, and elemental mapping results indicate the attachment of CuO nanoflowers with ZnO nanoflakes and also manifest the uniform attachment of Ag nanoparticles onto ZnO-CuO nanohybrids. X-ray photoelectron spectroscopy, Raman spectroscopy, and X-ray diffraction studies affirm the appearance of Ag@ZnO-CuO ternary nanohybrids. ZnO-CuO nanohybrids with uniformly attached Ag nanoparticles exhibit enhancement in the optical absorption spectra, while their PL studies indicate a significant decay in their PL intensity. Ag nanoparticles decorated ZnO-CuO nanohybrids decompose rhodamine (R6G) and oxytetracycline (OTC) molecules solution within 60 min under sunlight exposure. The improved lifetime of photogenerated charge carriers and the outstanding light-harvesting ability of Ag@ZnO-CuO nanohybrids effectively increase the photodegradation nature. Ag@ZnO-CuO ternary nanohybrids exhibit superior SERS-based efficient detection of rhodamine 6g (R6G) molecules. Enhanced photocatalytic activity and ultralow detection can be attributed to the effective charge transfer mechanism among Ag nanoparticles and ZnO-CuO nanohybrids. The present work explicitly reveals the contribution of Ag nano particles to the photodegradation nature and SERS-based detection of Ag@ZnO-CuO ternary plasmonic nano hybrids in a single platform.

Automated summary

The study demonstrates the superior performance of Ag nanoparticles functionalized ZnO-CuO nanohybrids in photocatalysis and SERS sensing, including enhancements in optical absorption and fluorescence, as well as the ability to degrade organic pollutants under sunlight exposure and efficiently detect rhodamine 6g molecules.