Annealing of BP-1300. u-BP-1300 was annealed at 800 °C for 1 hour under an Ar gas flow of 60 cm 3 min -1 Gas sorption. Low-pressure N2 isotherms (adsorption and desorption) were collected using an Anton Parr Autosorb iQ-XR at 77 K. An oven-dried sample cell (Type A long cell, 9 mm outer diameter, LG bulb) was tared before being loaded with a sample. Ex-situ degassing (110 °C, dynamic vacuum, 16 h) was performed before the evacuated tube was weighed again to determine the sample mass. Isotherms were collected over 24 -30 h, and the samples were reweighed following analysis to ensure accurate mass readings. Sorption isotherms were analyzed in AsiQwin version 5.21 software. Brunauer-Emmett-Teller (BET) surface areas were calculated from isotherms using the BET equation and Rouquerol's consistency criteria implemented in AsiQwin. DFT calculations used calculation model N2 at 77 K on carbon (slit pore, QSDFT equilibrium model).