Cobalt substitution in a flexible metal-organic framework: modulating a soft paddle-wheel unit for tunable gate-opening adsorption

Developing feasible ways to achieve tunable gate-opening pressure ( P go ) while minimizing the side effects on the adsorption capacity and enthalpy is greatly desired for flexible MOFs. In this work, we focused on solving this issue by cobalt substitution. We showed the successful modulation of the energy required for the reversible transformation of a soft paddle-wheel so that the whole framework presented a substitution-dependent P go for CO 2 adsorption. We achieved a tunable P go for gas adsorption in a flexible framework by modulating the dynamic rearrangement of coordination bonds of paddle-wheel unit via cobalt substitution.