Cerium-modified TiO2/g-C3N4 nanocomposites with synergistic effect on enhancing visible-light photocatalytic activity employing cationic dyes

Abstract

The present study focused on developing Cerium (Ce)-modified Titanium dioxide Oxide (TiO2)/Graphitic Carbon Nitride (g-C3N4) nanocomposites (NCs) using a hydrothermal synthesis approach to enhance photocatalytic activity under visible-light exposure. The as-prepared Ce-TiO2/g-C3N4 NCs were investigated by PXRD, UV-Vis DRS, FE-SEM with EDX mapping, HRTEM, XPS spectra and transient photocurrent response, respectively. The assessment of photocatalytic activity was conducted on the prepared materials, revealing a significant improvement in the photocatalytic performance of the Ce-TiO2/g-C3N4 NCs compared to pure TiO2 or g-C3N4 by facilitating the effective visible-light utilization ability, separation and transfer of photoinduced electron-hole pairs within the coupling of TiO2 and g-C3N4 matrix. The Ce-TiO2/g-C3N4 NCs exhibited remarkable degradation efficiency for the decomposition of cationic dyes, including Crystal Violet (CV), Methylene Blue (MB), and Rhodamine B (RhB), achieving degradation rates of 98%, 93%, and 83% within 120 min. Moreover, Trapping experiments revealed that the predominant reactive oxygen species responsible for degrading CV, MB, and RhB dyes with the Ce-TiO2/g-C3N4 catalyst was the O2̅ • radical. The possible photo-degradation mechanism and stability of the prepared Ce-TiO2/g-C3N4 catalyst were also proposed.