Investigating the synergistic effect of ZnO/GO nanocomposite films for methylene blue removal
Fatma Yıldırım, Nurtaç Canpolat, Şaki̇r Aydoğan, Mehmet Yılmaz
Abstract
Abstract This study aims to reveal the growth kinetics of ZnO nanoflakes and ZnO/GO nanocomposite films obtained at different Zn precursor salt concentrations by electrochemical deposition method and to evaluate the catalytic performances of the obtained films. The films were grown on FTO substrate with Zn precursor salt concentrations of 0.1 M, 0.125 M, and 0.175 M. Characterization of the obtained films was performed by XRD, SEM, UV–vis–NIR, Raman, and XPS analyses. The strong photocatalytic capabilities of the synthesized ZnO nanoflakes and ZnO/GO nanocomposite films were demonstrated by comparative analyses with the existing literature. Accordingly, photocatalytic experiments carried out under UVA irradiation revealed the high performance of the synthesized samples in the degradation of MB dye. The reaction kinetics were investigated using the Langmuir‐Hinshelwood kinetic model, resulting in high k obs values and R 2 coefficients. ZnO nanoparticles showed a k obs of 0.038 min −1 and an R 2 value of 0.96, while ZnO/GO nanocomposite films showed a k obs of 0.055 min − 1 and an R 2 value of 0.92. The significant increase in the degradation percentage shows the significant improvement achieved by the integration of GO, despite a slightly lower R 2 value for the ZnO/GO nanocomposite film compared with ZnO nanoflakes films.