**2. Materials and Methods**

All chemicals were obtained from commercial sources and were used without further purification. {[Co(34pba)(44pba)]·DMF}n (**1**), {[Co(34pba)(44pba)]·(C3H6O)}n (**2**), and {[Zn(34pba)(44pba)]·DMF}n (**3**) (44pba = 4-(4-pyridyl)benzoate and 34pba = 3-(4-pyridyl)benzoate) were solvothermally synthesized as detailed in Table 1. Compounds **1**, **2**, and **3** were activated at 210 ◦C under vacuum for 6 h which resulted in **1d**, **2d**, and **3d**, respectively. The activated samples were placed in narrow vials which were placed into larger vials containing VOCs and sealed to allow vapour sorption at room temperature (r.t., ca. 25 ◦C) for between one day and two weeks. The VOCs selected for study were dichloromethane (DCM), chloroform (CHCl3), chlorobenzene (ClBenz), water, ammonia, methylamine (MeNH2), 1-propylamine (PropNH2), 1-butylamine (ButNH2), benzylamine (BzNH2), and 1-phenylethylamine(PhEtNH2). The regeneration of the activated sorbents was carried out using the same conditions as for activation.

**Table 1.** Experimental conditions for the synthesis of **1**, **2**, and **3**.


Competitive sorption for chlorinated solvents was performed by placing equivalent volumes of two different solvents into a large vial and the relevant activated MOF into a small vial. The latter was then placed into the large vial and sealed for two days for the sorption of the vapours.

### *2.1. Thermogravimetric Analysis (TGA) and Di*ff*erential Scanning Calorimetry (DSC)*

Thermogravimetric analysis (TGA) was performed using a TA Instrument TA-Q500 on 1–2 mg samples in open platinum pans under nitrogen gas flow (50 mL min−1) at a heating rate of 10 ◦C min−<sup>1</sup> within the temperature range 25–500 ◦C. The onset temperature for gues<sup>t</sup> loss was determined using Differential scanning calorimetry (DSC). Samples of mass 1–2 mg were placed in aluminium pans with ventilated lids and heated at 10 ◦C min−<sup>1</sup> using a TA Instrument DSC-Q200 under nitrogen gas flow (50 mL min−1).
