Fig. 2: Structural characterizations and morphology of PY-DHBD-COF.

a AA-stacked structure and b AB-stacked structure of PY-DHBD-COF, the balls in different colors represent different atoms: C, gray; N, green; O, pink. c FT-IR spectra of PY-DHBD-COF, and the building monomers. d Experimental and simulated PXRD patterns of PY-DHBD-COF. e HAADF-STEM image of PY-DHBD-COF. f N2 adsorption isotherms of PY-DHBD-COF. Insert: pore size distribution of PY-DHBD-COF.