Nanographene-Based van der Waals Organic Framework With Permanent Porosity.

Porous crystalline materials traditionally rely on robust coordination or covalent bonds. Herein, we report a new C3-symmetric molecular nanographene 1 containing three hexabenzocoronene (HBC) units that self-organizes into a permanently porous framework exclusively using weak van der Waals interactions. Single-crystal x-ray diffraction results reveal a propeller geometry with C3 symmetry, forming two-dimensional honeycomb sheets parallel to the ab plane stabilized by π···π and C-H···π interactions. Nitrogen adsorption measurements at 77 K confirm a Type I(b) isotherm with a record-breaking Brunauer-Emmett-Teller (BET) surface area of 1108 m2 g-1, the highest reported to date for purely organic van der Waals frameworks. Furthermore, compound 1 exhibits aggregation-induced emission (AIE) and remarkable thermal stability up to 290° C. These results demonstrate that carefully designed nanographenes can achieve high structural predictability and robust porosity without the need for metal nodes or covalent linkages, opening new avenues for gas storage applications.