New Insights into Cd²⁺/Fe³⁺ Co-Doped BiOBr for Enhancing the Photocatalysis Efficiency of Dye Decomposition under Visible-Light

• Main Authors: Hong Sheng, Wei Wang, Rong Dai, Jing Ning, Lei Zhang, Qiao Wu, Fuchun Zhang, Junfeng Yan, Weibin Zhang
• Format: Article
• Language: English
• Published: MDPI AG 2021-02-01
• Series: Nanomaterials
• Subjects: BiOBr; Cd²⁺/Fe³⁺-doping; density function theory; microsphere; photocatalytic activity
• Online Access: https://www.mdpi.com/2079-4991/11/2/423
• ISSN: 2079-4991

Uniform flowerlike microspheres Cd²⁺/Fe³⁺ co-doped BiOBr were prepared with the aid of the microwave hydrothermal process. The results indicate that the degradation performance of Bi_1−<i>x</i>Cd<i>_x</i>OBr and Bi_1−<i>x</i>Fe<i>_x</i>OBr are 1.31 and 2.05 times that of BiOBr for RhB, respectively. Moreover, the novel Cd²⁺/Fe³⁺ co-doped BiOBr photocatalysts with ~0.42 eV impurity bands presented remarkably enhanced photocatalytic activities with being 3.10 times that of pure BiOBr, by achieving e⁻/h⁺ efficient separation and narrowed bandgap with the ions synergistic effect of Cd²⁺ and Fe³⁺. Based on DFT insights, the photodegradation mechanism was systematically studied that the conversion of multivalent Fe³⁺ ions promoted the production of •O₂⁻, and Cd²⁺ ions worked as electron transfer mediators, which elucidated that the •O₂⁻ and h⁺_VB mainly participated in the catalytic reaction. The experimental and theoretical results show that the synergistic effects of multi-ion doping have great potential in the field of photocatalysis.