Photocatalytic degradation of ethylene using titanium dioxide nanotube arrays with Ag and reduced graphene oxide irradiated by γ-ray radiolysis

Abstract

Titanium dioxide nanotube arrays (*TNTAs) made by anodic oxidation method and irradiated under 60Co-γ radiation combining with silver nanoparticles (AgNPs) and reduced graphene oxide (rGO) irradiated by 60Co-γ rays as well were investigated for photocatalytic degradation of ethylene in cold storage environment. Rate constant K of degradation was selected to describe the decomposition efficiency of ethylene with the new photocatalytic composite material (AgNPs/rGO-*TNTAs). Microstructure of the materials as prepared were characterized using analytic techniques: Atomic Force Microscope (AFM), Raman Spectroscopy, Fourier Transform Infrared Spectroscopy (FTIR), Field Emission Scanning Electron Microscope (FESEM), Transmission Electron Microscope (TEM), X-ray Diffraction (XRD) and X-ray Photoelectron Spectroscopy (XPS). We also compared the performance of five photocatalysts (Thermal annealing TNTAs, *TNTAs, rGO-*TNTAs, AgNPs-*TNTAs, AgNPs/rGO-*TNTAs) concerning ethylene decomposition. Results showed that AgNPs/rGO-*TNTAs exhibited enhancement of photocatalytic degradation of ethylene compared with rGO-*TNTAs and AgNPs-*TNTAs in photocatalytic process. Photocatalytic activity and structural evolution of photocatalysts irradiated by gamma rays and impact of the photocatalysts properties responsible for enhancing photocatalytic activity were discussed.