Thanks for your question, we looked up several literature and couldn't find a fixed usage of cracks and voids, and in this article, we think that using pores would completely cover our research objectives, so we deleted the cracks in this paper. Computed microtomography is usually used to confirm the voids in micron-scale but this paper focuses on nano-scale voids.
Response: In our previous work (Molecules 2020, 25, 443.