[Cu₃₆H₁₀(PET)₂₄(PPh₃)₆Cl₂] Reveals Surface Vacancy Defects in Ligand-Stabilized Metal Nanoclusters

Abstract

Precise identification and in-depth understanding of defects in nanomaterials can aid in rationally modulating defect-induced functionalities. However, few studies have explored vacancy defects in ligand-stabilized metal nanoclusters with well-defined structures, owing to the substantial challenge of synthesizing and isolating such defective metal nanoclusters. Herein, a novel defective copper hydride nanocluster, [Cu 36 H 10 (PET) 24 (PPh 3 ) 6 Cl 2 ] (Cu36; PET: phenylethanethiolate; PPh 3 : triphenylphosphine), is successfully synthesized at the gram scale via a simple one-pot reduction method. Structural analysis reveals that Cu36 is a distorted half cubic nanocluster, evolved from the perfect Nichol's half cube. The two surface copper vacancies in Cu36 are found to be the principal imperfections, which result in some structural adjustments, including copper atom reconstruction near the vacancies as well as ligand modifications (e.g., substitution, migration, and exfoliation). Density functional theory calculations imply that the above-mentioned defects have a considerable influence on the electronic structure and properties. The modeling suggests that the formation of defective Cu36 rather than the perfect half cube is driven by the enlargement of the energy gap between the highest occupied molecular orbital and the lowest unoccupied molecular orbital of the nanocluster. The structural evolution induced by the surface copper atom vacancies provides atomically precise insights into the defect-induced readjustment of the local structure and introduces new avenues for understanding the chemistry of defects in nanomaterials.

[Cu18H3(S-Adm)12(PPh3)4Cl2]: fusion of Platonic and Johnson solids through a Cu(0) center and its photophysical properties

“…This arrangement creates multiple point defects in the structure, which triggered plausible reconstructions in the remaining part of the structure. 29 Two Cu 2 units belonging to the metal-ligand motifs of Cu 18 NC exhibit a rotation of 90 in comparison to Ag 23 NC (Fig. 3b and c).…”

“…24 The interaction of coinage metals with the thiolbased protecting ligands is very important for stability, charge transport properties, and photoluminescence behavior. [25][26][27] Osman M. Bakr and co-workers have investigated this area extensively and successfully synthesized various Cu NCs (such as Cu 15 , 28 Cu 36 , 29 Cu 61 , 30 Cu 81 (ref. 31)) co-protected with different thiolate ligands (phenylethanethiol, tert-butyl thiol, benzene thiol), among which only Cu 61 has partial Cu(0) character.…”

“…14,28,30,31,34 In addition, the smaller size of the Cu atom in comparison with that of Au and Ag will inuence the formation vacancy-induced or distorted architecture NCs. 29,35 However, the crystal structures of such NCs with vacancies have not been explored much. Thus, the lack of structural information for thiolate-protected Cu NCs seriously connes our understanding of their structure-property correlations and the search for their cutting-edge applicability.…”

Tetrametallic Copper Complex to Nanoscale Copper: Selective and Switchable Dehydrogenation‐Hydrogenation under Light

“…To date, various structurally characterized NCs have been used for catalytic, photocatalytic and electrocatalytic reactions [5,6] . Despite the great progress that has been achieved over the past few decades in the synthesis and use of NCs, the isolation of Cu 0 nanoclusters is still difficult due to their low stability and ultrasmall size [7–9] . Most importantly, the lower M I /M 0 half‐cell potential of Cu (0.52 V) makes them prone to oxidation.…”

“…[5,6] Despite the great progress that has been achieved over the past few decades in the synthesis and use of NCs, the isolation of Cu 0 nanoclusters is still difficult due to their low stability and ultrasmall size. [7][8][9] Most importantly, the lower M I /M 0 half-cell potential of Cu (0.52 V) makes them prone to oxidation. However, ultrafine NCs of copper and its oxidized product could be a potential candidates [10,11] for possible use as stimuli (light/ O 2 )-responsive switchable bifunctional catalysts with precise control over chemical transformation.…”