Fig. 4: Direct observation of molecular-level recrystallization process.

a Serial HRTEM images of UiO-66(Hf) crystals along the [1\(\bar{1}\)0] projection, after correcting CTF effects, under increasing accumulated electron dose in vacuum. b–e Magnified views of ROIs marked by white, yellow, blue, and green dashed rectangles in (a), accompanied by schematic illustrations of the structural models. The HRTEM images are rendered in a black-body false-color code. Blue represents the Hf6O4(OH)4 nodes, red indicates BDC linkers with broken bonds, and yellow indicates pristine BDC linkers.