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Manipulation of the oxidation states of the metal species within metal−organic frameworks leads to compositional, structural, and surface property evolutions, which will impact their performance as sorbents in adsorptive separation processes. In this study, we propose a new low-cost postsynthesis strategy to modify the oxidation states of copper species within the copper-1,3,5-benzenetricarboxylic acid (Cu-BTC) structure employing Na 2 S 2 O 3 as the reducing agent. The compositional and structural evolutions of the modified samples were thoroughly characterized by a series of methods, and the dimethyl disulfide (DMDS) adsorption performance was evaluated. Accurately controlled reduction of Cu(II) to Cu(I) and formation of nanopores in the modified Cu(I)/Cu(II)-BTC samples have been observed and confirmed experimentally. Specifically, the sample 0.46/Cu-BTC/24h with a Cu(I)/Cu(II) molar ratio of 1.79 exhibits both the highest DMDS adsorption capacity (146.66 mg-S/g) and fastest diffusion with D of 7.59 × 10 −13 cm 2 /s at 298 K. Further density functional theory calculations reveal that the modified Cu(I)/Cu(II)-BTC structures exhibit much higher interaction energy, E in , with DMDS (70.65 kJ/mol) than the parent Cu(II)-BTC (20.28 kJ/mol). Controllable reduction of Cu(II) to Cu(I) in Cu-BTC leads to significantly enhanced guest−host interactions as well as the formation of uniform nanoscale porosity leading to effect enhancement for the adsorption of DMDS using modified Cu-BTC materials.

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