Ligand-dependent non-monotonic electron beam-induced structural degradation in 2D MOFs

Two-dimensional metal-organic frameworks (2D-MOFs) are promising for separations, sensing, and nano-optoelectronics. However, their integration with electron beam fabrication and imaging is limited by beam-induced structural damage. Here, we show that ligand chemistry governs non-monotonic, plane-specific electron beam responses in archetypal 2D-MOFs. Using low-dose serial electron diffraction at 300 kV, we quantify degradation pathways and critical doses for Zn-TCPP (porphyrinic carboxylate) and Zn2(benzimidazolate)4. Zn-TCPP exhibits a two-stage evolution in which early ligand-assisted rearrangement transiently strengthens selected Bragg planes before the pristine unit cell collapses at higher cumulative dose. In contrast, Zn2(benzimidazolate)4 undergoes a direct transition to amorphization consistent with progressive Zn-N4 breakdown. The extracted, ligand-resolved dose thresholds define practical windows for low-dose transmission electron microscopy, deterministic defect creation, and electron-beam lithography (EBL), with conversions to standard exposure units provided. These results reframe the electron beam from liability to design tool and supply quantitative guidelines for reliable patterning and characterization of 2D-MOFs.