(a–d) FESEM images show the morphology of the BiOClxBr1−x flower-like 3D structures at different magnifications. Reproduced with permission [27]. Copyright 2015, John Wiley and Sons. (e) SEM images implying the morphology of BiOClxI1−x (x = 1, 0.8, 0.6, and 0.4) synthesized in ethylene glycol (the first two columns from left) and water (the last column). The inset camera pictures imply the color of the related samples. Reproduced with permission [197]. Copyright 2014, Elsevier. (f) Schematic illustration of the underlying mechanism for the enhanced MO adsorption in a BiOClxIy solid solution. Reproduced with permission [198]. Copyright 2016, Elsevier.