Nanosheet g-C3N4 enhanced by Bi2MoO6 for highly efficient photocatalysts toward photodegradation of Rhodamine-B dye

Heliyon. 2023 Nov 13;9(11):e22342. doi: 10.1016/j.heliyon.2023.e22342. eCollection 2023 Nov.

Abstract

The investigation of a proficient photocatalytic system for the degradation of organic pollutants holds significant importance in the field of environmental management. This study presents a binary type II heterojunction photocatalyst, Bi2MoO6/g-C3N4 which is synthesized using an eco-friendly ultrasonic-assisted method. Various characterization methods (XRD, FTIR, XPS, BET, TEM, UV-vis, and PL) are used to investigate the crystalline structures, composition, surface analysis, morphology, and optical properties of the photocatalyst. All the Bi2MoO6/g-C3N4 nanocomposites show better photocatalytic activity for Rhodamine B dye (Rh-B) degradation under Ultraviolet light irradiation than the pure g-C3N4. The photocatalytic activity of the 10 % Bi2MoO6/g-C3N4 nanocomposite is found to be the greatest among the tested samples. the 10 % Bi2MoO6/g-C3N4 nanocomposite demonstrates the ability to degrade 94.6 % of Rh-B (1 × 10-5 M) within 3 h, with a rate constant of 0.015 min-1. Notably, this rate constant is 7 times greater than that observed for pure g-C3N4, which has a rate constant of 0.00218 min-1. The effect of several reaction factors on the Rhodamine B (Rh-B) removal is studied. The enhanced photocatalytic activity of 10 % Bi2MoO6/g-C3N4 nanocomposite is mainly due to the formation of 2D/2D type II structures, increasing the active sites and the separation rate of photogenerated carriers. A possible photocatalytic reaction mechanism of Rhodamine B (Rh-B) degradation over Bi2MoO6/g-C3N4 is suggested based on active species trapping experiment. Moreover, the high stability and recyclability exhibited by the 10 % Bi2MoO6/g-C3N4 nanocomposite provide strong evidence supporting its suitability as a viable photocatalyst for wastewater treatment purposes.

Keywords: 2D nanosheet; Bi2MoO6 nanoplates; Binary heterostructure; Photocatalysis; Rh–B dye.