@article{Liu2026, 
author = {Ziyi Liu and Siqi Li and Lancheng Zhao and Lubing Qin and Jingwen Yang and Tao Wu and Likai Wang and Qing Tang and Zhenghua Tang},
title = {Alkynyl-protected Cu67 nanocluster superatom: Structure anatomy and electrochemical CO2 reduction study},
year = {2026},
journal = {Nano Research},
volume = {19},
number = {2},
pages = {94908145},
keywords = {density functional theory calculations, electrochemical CO2 reduction, hierarchical structure, [Cu67(C≡CPh)24(OAc)18]− (Cu67) nanoclusters, in-situ spectroscopic study},
url = {https://www.sciopen.com/article/10.26599/NR.2025.94908145},
doi = {10.26599/NR.2025.94908145},
abstract = {Atomically precise high-nuclearity Cu nanoclusters (Cu atom number > 50) with both Cu(I) and Cu(0) species have been rarely reported due to the inherent instability of Cu(0) species. Herein, we report a C3 symmetric alkynyl-protected [Cu67(C≡CPh)24(OAc)18]− (Cu67; Ph and OAc refer to phenyl group and acetate, respectively) superatomic nanocluster, which possesses a hierarchical metal core structure of Cu5@Cu26@Cu36. Cu67 was synthesized by a one-pot reduction strategy in which phenylacetylene drives the assembly of a nested architecture stabilized by synergistic μ-coordinated alkynyl ligands (μ4/μ5 modes) and κ2-bridged acetates. Remarkably, when Cu67 is used for electrochemical CO2 reduction reaction (eCO2RR), deeply reduced hydrocarbon chemicals, especially the C2+ products, with high selectivity are acquired. Specifically, Cu67 achieves a Faradaic efficiency (FE) of 56.32% for the total C2+ products at −0.9 V vs. reversible hydrogen electrode (RHE), among which the FE of ethylene ( FEC2H4) is 39.01%. The excellent catalytic performance from Cu67 is superior to most of the recently reported Cu nanocluster-based catalysts. In-situ attenuated total reflection surface-enhanced infrared absorption spectroscopy (ATR-SEIRAS) study reveals the reaction pathway and identifies the key intermediate *COCHO for yielding C2+ products. Density functional theory (DFT) calculations systematically elucidate the reaction mechanism of eCO2RR on Cu67 to generate CO and C2H4, where the transformation from *CO to *CHO is the rate-determining step for generating the C2+ products. This work not only enriches the family members of alkynyl-protected high-nuclearity superatomic Cu nanoclusters, but also provides atom-level mechanistic insights on employing Cu nanoclusters for eCO2RR to produce highly valuable products.}
}