Comparison of the IR spectra of the precursor and the COF revealed the absence of the characteristic C≡N peak at 2242 cm⁻¹ in the COF material. Additionally, the two peaks at 3385 cm⁻¹ and 3354 cm⁻¹, indicative of the primary amine N-H stretch of DAB, were absent (Figure ). Instead, a broad stretch between 3500 cm⁻¹ and 3000 cm⁻¹ was observed, which can be attributed to the secondary amine N-H stretch in the COF (Figure ). The PXRD of the synthesized COF shows two peaks at 5.8° and 26.4°. From structural simulation (Figure ), the former was assigned to the (100) plane and the latter to the (001) plane. The measured PXRD is closely matched with the AA stacking type in simulated stacking model (Figure and S7) mainly due to missing (101) peak around 14 degrees. The broad nature of the bands is due to the short-range order of the COF. Particularly, the broad peak at 26° can be assigned to the π-π stacking with a layer distance of 3.37 Å, which corresponds well with the simulated interlayer distance of 3.47 Å (Figure ). The robustness of the COF was also tested by recording the PXRD and IR after immersing it in acidic and basic media for 7 days. It was found that there is no change in the spectra indicating the high stability of the COF. This is because of the inherent stability to the phenazine linkages in the COF which constitute of -C=N-and -C-N-bonds. ) and correspond to the H's associated with the aromatic moiety and the N-H in the framework. The remaining resonance at around 1.5 ppm, is likely due to a small amount of residual NMP absorbed into the pores of HAT-DAB COF. The 13 C NMR displays a broad peak consisting of a number of overlapping resonances across the δ range of 130-160 ppm, that can be collectively ascribed to the C=C and C=N moiety carbons of the COF framework (Figure ).