Akademik Veri Yönetim Sistemi
Chemical Engineering Research and Design, cilt.223, ss.578-593, 2025 (SCI-Expanded, Scopus)
In this study, we developed substrate-free graphene and graphene/metal oxide electrodes and systematically evaluated their effectiveness for phenol degradation. Graphite oxide was synthesized from commercial graphite using the Torr method, and stable graphene oxide dispersions were prepared by ultrasonic-assisted exfoliation. Additionally, graphene-metal oxide (GR-MO) films were fabricated from GR/TiO2, GR/PtO2, and GR/SnO2 dispersions through filtration and/or casting methods. The properties of both GR and GR-MO were characterized using SEM, XRD, FT-IR, and cyclic voltammetry (CV) analysis. The characterization confirmed successful metal oxide doping in all GR/MO films produced. Similar to graphene films, the GR/MO films exhibited thin film morphology, high thermal reduction temperatures, enhanced conductivity, and better stacking order. Metal oxide dispersion was observed on both the surface and within the cross-sectional films after doping. This study also examined the influence of various electrooxidation (EO) process parameters on phenol degradation, including current density, pH, and phenol concentration. Under optimal conditions (j 30 mA/cm2, pH 5, SEc 4 g Na2SO4/L, Cphenol 300 mg/L), the GR electrode achieved a treatment efficiency of 53.6 % after 180 min, while the GR/PtO2 electrode reached 60.0 % efficiency under identical conditions. Furthermore, although GC-MS detected multiple intermediate phenol degradation products, LC-MS/MS provided superior sensitivity, accuracy, and reproducibility. On the other hand, complementary analyses by HPLC and UV-Vis spectroscopy were also employed to evaluate phenol removal efficiency, elucidate the EO mechanism, and identify potential toxic by-products. These findings highlight GR/PtO2 electrodes as a pioneering and scalable platform for the electrochemical oxidation of phenolic pollutants.