Controlled Shell and Kernel Modifications of Atomically Precise Pd/Ag Superatomic Nanoclusters

• Published in: Chemistry : a European journal 2023-06, Vol.29 (31), p.e202300730-n/a
• Main Authors: Ni, Yu‐Rong, Pillay, Michael N., Chiu, Tzu‐Hao, Wu, Ying‐Yann, Kahlal, Samia, Saillard, Jean‐Yves, Liu, C. W.
• Format: Article
• Language: English
• Subjects: atomically precise nanoclusters; Catalysis; Chemical reduction; Chemical Sciences; Chemistry; dithiophosphate; Hydrides; Isomers; Magnetic resonance spectroscopy; Material chemistry; Nanoclusters; Nitrophenol; NMR; NMR spectroscopy; Nuclear magnetic resonance; or physical chemistry; Palladium; palladium hydrides; Redox reactions; Room temperature; Silver; superatoms; Tetrahedra; Theoretical and; Trifluoroacetic acid
• ISSN: 0947-6539; 1521-3765
• DOI: 10.1002/chem.202300730

The first 8‐electron Pd/Ag superatomic alloys with an interstitial hydride [PdHAg19(dtp)12] (dtp=S2P(OiPr)2−) 1 and [PdHAg20(dtp)12]+ 2 are reported. The targeted addition of a single Ag atom to 1 is achieved by the reaction of one equivalent of trifluoroacetic acid, resulting in the formation of 2 in 55 % yield. Further modification of the shell results in the formation of [PdAg21(dtp)12]+ 3 via an internal redox reaction, with the system retaining an 8‐electron superatomic configuration. The interstitial hydride in 1 and 2 contributes its 1s1 electron to the superatomic electron count and occupies a PdAg3 tetrahedron. The distributions of isomers corresponding to different dispositions of the outer capping Ag atoms are investigated by multinuclear VT NMR spectroscopy. The emissive state of 3 has a lifetime of 200 μs (λex=448; λem=842), while 1 and 2 are non‐emissive. The catalytic reduction of 4‐nitrophenol is demonstrated with 1–3 at room temperature. The first controlled modification of kernel and shell arrangements in Pd‐doped superatomic silver clusters containing interstitial hydrides is presented. The sequential addition of individual Ag atoms to an icosahedron core results in PdH@Ag19, PdH@Ag20, and Pd@Ag21, while maintaining a 12‐ligand stabilizing framework. Remarkable aqueous stability, proven by unsupported catalytic reduction of 4‐nitrophenol was demonstrated.