Design of Z-scheme g-C3N4/BC/Bi25FeO40 photocatalyst with unique electron transfer channels for efficient degradation of tetracycline hydrochloride waste

• Published in: Chemosphere (Oxford) Vol. 289; p. 133262
• Main Authors: Ma, Zhi-Peng, Zhang, Linnan, Ma, Xue, Zhang, Yu-Hang, Shi, Fa-Nian
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.02.2022
• Subjects: Bi25FeO40; Biochar; g-C3N4; Photocatalytic degradation; Tetracycline hydrochloride; Z-scheme g-C3N4/BC/Bi25FeO40; g-C3N4; Photocatalytic degradation; Tetracycline hydrochloride; Bi25FeO40; Biochar; Z-scheme g-C3N4/BC/Bi25FeO40
• ISSN: 0045-6535; 1879-1298
• DOI: 10.1016/j.chemosphere.2021.133262

High electron transfer rates and a higher number of electron transfer active sites play important roles in inhibiting the recombination of photogenerated electron-hole pairs. In the experiments described in this article, the g-C3N4/BC/Bi25FeO40 composite material was prepared to use biochar (BC) as the conductive channel. The presence of BC significantly increases the electron transfer rate due to its excellent electrical conductivity and can provide more electron transfer active sites. At the same time, BC provides a larger surface area and has a loose porous structure, which lead to excellent adsorption performance. Based on various characterization results, it was confirmed that the Z-scheme heterojunction was successfully constructed between g-C3N4 and Bi25FeO40. The photocatalytic experiment results showed that the degradation efficiency of g-C3N4/BC/Bi25FeO40 on the tetracycline hydrochloride (TCH) could reach 92.2% within 60 min. Parameters such as circulation stability, pH value of the solution and the amount of composite materials were studied. The synthesized composite material has good reusability and high efficiency in a wide pH range of 3–11. Its excellent photocatalytic activity is attributed to the formation of an effective Z-scheme heterostructure, as well as the rapid photoelectron transfer and excellent adsorption capacity of BC. This work provides a way to design new photocatalysts using semiconductor composite materials and BC materials. [Display omitted] •A new Z-scheme g-C3N4/BC/Bi25FeO40 was developed for photocatalytic TCH degradation.•BC as a conductive channel greatly improved the transmission rate of electrons.•The strong adsorption capacity of BC promoted the degradation rate of TCH.•g-C3N4/BC/Bi25FeO40 displayed well degradation effect in a wide range of pH (3–11).