New Insights into Cd(2+)/Fe(3+) Co-Doped BiOBr for Enhancing the Photocatalysis Efficiency of Dye Decomposition under Visible-Light

Uniform flowerlike microspheres Cd(2+)/Fe(3+) co-doped BiOBr were prepared with the aid of the microwave hydrothermal process. The results indicate that the degradation performance of Bi(1−x)Cd(x)OBr and Bi(1−x)Fe(x)OBr are 1.31 and 2.05 times that of BiOBr for RhB, respectively. Moreover, the novel Cd(2+)/Fe(3+) 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 Cd(2+) and Fe(3+). Based on DFT insights, the photodegradation mechanism was systematically studied that the conversion of multivalent Fe(3+) ions promoted the production of •O(2)(−), and Cd(2+) ions worked as electron transfer mediators, which elucidated that the •O(2)(−) 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.