Two-Dimensional Supramolecular Nanoarchitectures of Polypseudorotaxanes Based on Cucurbit[8]uril for Highly Efficient Electrochemical Nitrogen Reduction

Supramolecular assemblies with two-dimensional (2D) topology have drawn great attraction in the development of functional materials through a modular approach. Herein, a novel organic 2D polypseudorotaxane has been constructed on the basis of cucurbit[8]uril (CB[8]) through host-stabilized charge-transfer (CT) interactions of naphthol-modified porphyrin (TPP-Np) and viologen derivatives (DMV). Interestingly, the 2D polypseudorotaxanes could serve as a platform for preparation of ultrafine Pt nanoparticles with favorable and homogeneous dispersion through a simple self-metallized process, leading to the formation of supramolecular hybrid materials (PtNPs@(CB[8]/DMV/TPP-Np)). Surprisingly, the PtNPs@(CB[8]/DMV/TPP-Np) could be applied to efficient electrochemical nitrogen reduction reaction, with a NH3 yield rate up to 23.2 μg h–1 mgPt–1 at −0.2 V versus a reversible hydrogen electrode under ambient conditions. Notably, our results not only demonstrate the feasible construction of 2D polypseudorotaxanes but also deepen the understanding of structure–activity relationships in supramolecular nanoarchitectures, as well as pave an effective and low-energy input strategy for artificial nitrogen fixation.