The photocatalytic performance of ternary g-C3N4/Bi2O3/TiO2 heterojunction composite for degradation of organic pollutants under visible and ultraviolet light

Heterojunction photocatalytic materials have received extensive attention by the researchers. In this work, g-C 3 N 4 /Bi 2 O 3 /TiO 2 (TCB) composites with g-C 3 N 4 as the main body were synthesized via microwave-assisted ball milling and the heat treatment method. The photocatalytic activity was evaluated by the degradation efficiency of rhodamine B (RhB) and methylene blue (MB) under visible or UV light irradiation. TCB with a mass ratio of melamine/TiO 2 /Bi(NO) 3 ·5H 2 O of 30:1:0.25 has the best photocatalytic performance when fabricated at 450 °C in open air, and the degradation efficiency of the as-prepared material to RhB was 48.07% under visible light and 51.18% to MB under UV. The results of morphological structure analysis revealed that there was a flocculent structure on the edge of the g-C 3 N 4 film and the phase of TiO 2 and Bi 2 O 3 changed. The presence of β-Bi 2 O 3 enhanced photocatalytic efficiency of the as-prepared materials. The optical properties analysis confirmed that the structure of the hybrid samples can promote electron–hole pairs separately at multilayer heterogeneous interfaces and the electron can react with O 2 to yield the · O 2 - radical. In summary, the ability of novel spatial structure materials to absorb visible light is enhanced, which are facilitated for photocatalytic activity and have excellent stability. Therefore, the study of ternary heterojunction photocatalytic materials provides a reference for environmental remediation.