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Capped chelating organic molecules are presented as a design principle for tuning heterogeneous nanoparticles for electrochemical catalysis. Gold nanoparticles (AuNPs) functionalized with a chelating tetradentate porphyrin ligand show a 110‐fold enhancement compared to the oleylamine‐coated AuNP in current density for electrochemical reduction of CO2 to CO in water at an overpotential of 340 mV with Faradaic efficiencies (FEs) of 93 %. These catalysts also show excellent stability without deactivation (<5 % productivity loss) within 72 hours of electrolysis. DFT calculation results further confirm the chelation effect in stabilizing molecule/NP interface and tailoring catalytic activity. This general approach is thus anticipated to be complementary to current NP catalyst design approaches.

Reported here is the chelate effect as ad esign principle for tuning heterogeneous catalysts for electrochemical CO 2 reduction. Palladium functionalizedw ith ac helating tris-N-heterocyclic carbene (NHC) ligand (Pd-timtmb Me ) exhibits a3 2-fold increase in activity for electrochemical reduction of CO 2 to C1 products with high Faradaic efficiency (FE C1 = 86 %) compared to the parent unfunctionalized Pd foil (FE = 23 %), and with sustained activity relative to am onodentate NHC-ligated Pd electrode (Pd-mimtmb Me ). The results highlight the contributions of the chelate effect for tailoring and maintaining reactivity at molecular-materials interfaces enabled by surface organometallic chemistry.

We reported the synthesis of a tris­(triazolylmethyl)­amine (TTA)-bridged organosilane, functioning as Cu­(I)-stabilizing ligands, and the installation of this building block into the backbone of mesoporous organosilica nanoparticles (TTASi) by a sol–gel way. Upon coordinating with Cu­(I), the mesoporous CuI-TTASi, with a restricted metal active center inside the pore, functions as a molecular-sieve-typed nanoreactor to efficiently perform Cu­(I)-catalyzed alkyne–azide cycloaddition (CuAAC) reactions on small-molecule substrates but fails to work on macromolecules larger than the pore diameter. As a proof of concept, we witnessed the advantages of selective nanoreactors in screening protein substrates for small molecules. Also, the robust CuI-TTASi could be implanted into the body of animal models including zebrafish and mice as biorthogonal catalysts without apparent toxicity, extending its utilization in vivo ranging from fluorescent labeling to in situ drug synthesis.

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