Construction of heterojunction g-C3N4/CoAl hydrotalcites for high-efficient Cr(VI) reduction under visible light

• Published in: Applied clay science 2020-08, Vol.193 (C), p.105669, Article 105669
• Main Authors: Xiong, Jie, Xiao, Gao-Fei, Zeng, Hong-Yan, Chen, Chao-Rong, An, De-Shun
• Format: Article
• Language: English
• Subjects: CoAl hydrotalcite; Composites; G-C3N4; Heterostructure; Photoreduction
• ISSN: 0169-1317; 1872-9053
• DOI: 10.1016/j.clay.2020.105669

The novel composites of graphitic carbon nitride (g-C3N4) and CoAl hydrotalcite (LDH) were synthesized using a hydrothermal method, for which photocatalytic reduction performances were evaluated using Cr(VI) as a target pollutant. The results indicated that the incorporation of g-C3N4 to CoAl-LDH could improve Cr(VI) photoreduction activity in connection with the adding amounts of g-C3N4 during the preparation process. The g-C3N4/LDH1.6 prepared in 1.6 g·L−1 g-C3N4 showed the highest Cr(VI) reduction activity, which was 10.1 and 3.6-folds higher than that of pure g-C3N4 and CoAl-LDH under visible-light irradiation, respectively. The enhanced photocatalytic activity benefited from the synergistic effect in the heterojunction electric field on the interface between the g-C3N4 and CoAl-LDH, which accelerated the electron transfer and separation of photogenerated electrons and holes. The results make the heterojunction material a potential candidate for environmental restoration. [Display omitted] •The novel g-C3N4/LDH composite was successfully prepared.•Incorporation of g-C3N4 to CoAl-LDH could improve Cr(VI) photoreduction ability.•Charge separation and transfer were promoted in interfacial heterojunction field.