Gram-Scale Preparation of Stable Hydride M@Cu24 (M = Au/Cu) Nanoclusters

The instability of phosphine ligated copper hydride nanoclusters (CuH NCs) has largely limited their application in areas such as H-2 storage, CO2 reduction, etc. In this work, the stability of CuH NCs was remarkably enhanced by improving their antioxidant capacity through two different approaches: (i) metal doping and (ii) ligand modification. Three NCs, AuCu24H22(PPh3)(12), Cu25H22((p-FPh)(3)P)(12), and AuCu24H22((p-FPh)(3)P)(12), were controllably synthesized, and their structures were determined by single-crystal X-ray diffraction. The compositions of these NCs were further confirmed by electrospray ionization mass spectrometry and nuclear magnetic resonance. More importantly, we achieved gram-level production of M@Cu-24 (M = Cu/Au) NCs protected by electron-withdrawing ligands (p-FPh)(3)P, which in turn proved their superior stability; such a large-scale preparation laid the foundation for future explorations of copper-rich NCs. This work hopes to shed light on large-scale generation of ultrastable Cu-based NCs.