Comment on “Novel formation of Bi@BiFe-glycolate hollow spheres and their conversion into Bi2O3/BiFeO3 composite hollow spheres with enhanced activity and durability in visible photocatalysis” by X. Yang, J. Meng, Y. Wang, Q. Meng, Y. Hu, A. Di, Y. Wu and G. Chen, New J. Chem., 2018, 42, 10697
In this comment, we found that the explanations in the paper of X. Yang et al. were not accurately stated, which could cause confusion and misunderstanding. We hope that this comment can clarify this paper and provide more precise insights into the work of X. Yang et al. Also, the new mechanism of the enhanced activity of photocatalysis was discussed from our point of view, and the effective band gap of the composite can be calculated, which can possibly be an important factor for indicating the activity of the photocatalyst.