Unprecedented Li<sup>+</sup> Exchange in an Anionic Metal–Organic Framework: Significantly Enhanced Gas Uptake Capacity

We herein report the first example of Li<sup>+</sup> exchanged with both the guest H<sub>2</sub>N­(Me)<sub>2</sub><sup>+</sup> cations located in the channels and the coordinated metal ions from an anionic metal–organic framework (MOF), leading to significant enhancement of the pore volume and gas sorption abilities of the exchanged MOF. Furthermore, both MOFs before and after Li<sup>+</sup> exchange show good selective adsorption for CO<sub>2</sub> over CH<sub>4</sub>.