Decoding Desulfurization Pathways in Metal–Organic Frameworks (MOFs) via Experimental and Computational Approaches: A Step toward Sustainable Fuel Purification
Mohd Mehtab, Mohd Zeeshan, Manjeet Kumar, Azaj Ansari, Mohammad Yasir Khan, Farasha Sama, MUSHEER AHMAD, M. Shahid
Abstract
Two new metal–organic frameworks, {[Cu 2 (BPDC) 2 (Bipy) 2 ]·2DMF} n ( MM-1 ) and {[Zn 3 (BPDC) 3 (Bipy)]4H 2 O·2DMF} n ( MM-2 ), were synthesized using biphenyl-4,4′-dicarboxylic acid (BPDC) and 4,4′-bipyridine (Bipy) mixed linkers via a solvothermal route. Single-crystal X-ray diffraction (SCXRD) showed both frameworks adopt an sra topology with robust 3D architectures stabilized by π–π and metal–ligand interactions. FTIR, TGA, BET, PXRD, and XPS analyses confirmed structural integrity and coordination environments. XPS identified Cu 2+ centers in MM-1 (Cu 2p 3/2: 933.38 eV; Cu 2p 1/2: 951.24 eV) and Zn 2+ centers in MM-2 (Zn 2p 3/2: 1022.97 eV; Zn 2p 1/2: 1045.42 eV), while N 1s peaks at 398.5 and 399.8 eV verified coordinated and uncoordinated pyridyl nitrogen. N 2 sorption studies at 77 K revealed mesoporosity with surface areas of 597.29 m 2 g –1 ( MM-1 ) and 128.97 m 2 g –1 ( MM-2 ). MM-1 showed excellent dibenzothiophene (DBT) and benzothiophene (BT) adsorption capacities of 91.82 and 78.80 mg g –1, respectively, achieving ∼87% DBT removal-superior to most reported MOFs. Further, DFT calculations supported strong thermodynamic binding, with mode 4 exhibiting the most favorable adsorption energy due to π–π stacking and O···S interactions. The synergy between open Cu 2+ sites, high surface area, and the strong host–guest interactions positions MM-1 as a promising desulfurization material.