a Molecular structure of pyrogallolarene (PgCn, n = 3, 5, 9) and the crystal structure of the uranyl complex [U24(PgC3)6]. b Distribution ratios (errors ranging from 0.3 to 35.7%) for uranyl and lanthanide ions at different pH and cartoon representation of selective assembly of nanocages during extraction. Reproduced with permission from ref. 19. Copyright 2020 American Chemical Society.