Enhancing Electrochemical Signal for Efficient Chiral Recognition by Encapsulating C₆₀ Fullerene into Chiral Lanthanum-Based MOFs

Chiral metal–organic frameworks (MOFs) have attracted much attention due to their highly tunable regular microporous structures. However, chiral electrochemical recognition based on chiral MOFs is often limited by poor charge separation and slow charge transfer kinetics. In this case, C 60 can be encapsulated into the cavity of [La(BTB)] n by virtue of host–guest interactions through π–π stacking to synthesize the chiral composite C 60 @[La(BTB)] n and amplify electrochemically controlled enantioselective interactions with the target enantiomers. A large electrostatic potential difference is generated in chiral C 60 @[La(BTB)] n due to the host–guest interaction and the inhomogeneity of the charge distribution, leading to the generation of a strong built-in electric field and thus an overall enhancement of the conductivity of the chiral material. Their enantioselective detection of tryptophan enantiomers was demonstrated by electrochemical measurement. The results showed that chiral MOF materials can be used for enantiomeric recognition. It is worth noting that this new material derived from the concept of host–guest interaction to enhance charge separation opens up unprecedented possibilities for future enantioselective recognition and separation.