Construction of g-C3N4/CeO2 composites with enhanced carrier separation for efficient photocatalytic activity

Abstract

The urgent need for effective and environmentally friendly technologies in addressing organic pollution in water bodies has become increasingly apparent. Photocatalytic degradation, characterized by its green and energy-efficient nature, has garnered significant attention. This study focuses on the low visible-light utilization efficiency of g-C 3 N 4 and proposes an innovative approach by constructing g-C 3 N 4 /CeO 2 composite materials to significantly enhance photocatalytic performance. Porous g-C 3 N 4 and CeO 2 nanosheets were synthesized via pyrolysis and hydrothermal methods, respectively. Subsequently, three composites with different ratios (CeCN2.5, CeCN5, and CeCN10) were successfully fabricated by combining them in organic solvents. Characterization techniques including XRD, SEM, and XPS confirmed that the composites exhibited uniform structures and favorable band alignment, leading to the formation of Z-scheme heterojunctions. In practical photocatalytic degradation applications, CeCN5 exhibited a degradation efficiency of 93.77%, representing a 21.92% improvement compared with pure g-C 3 N 4 . The rate constant for CeCN5 was determined to be 0.044 min[Formula: see text], which is 1.8 times higher than that of the individual component. Free-radical trapping experiments further confirmed that h[Formula: see text] and ⋅ OH were the primary active species responsible for the catalytic activity. Additionally, after three consecutive cycles, the degradation efficiency of CeCN5 remained at 84.53%, highlighting its excellent stability and reusability. This study offers valuable insights into the design of highly efficient photocatalysts and provides significant implications for the treatment of organic pollutants.