From M to M, M and M molecular alloy Pt-Ni carbonyl nanoclusters: selective growth of atomically precise heterometallic nanoclusters

• Published in: Dalton transactions : an international journal of inorganic chemistry 2023-03, Vol.52 (12), p.3623-3642
• Main Authors: Cesari, Cristiana, Berti, Beatrice, Bortoluzzi, Marco, Femoni, Cristina, Funaioli, Tiziana, Vivaldi, Federico Maria, Iapalucci, Maria Carmela, Zacchini, Stefano
• Format: Article
• ISSN: 1477-9226; 1477-9234
• DOI: 10.1039/d2dt03607j

Heterometallic Chini-type clusters [Pt 6− x Ni x (CO) 12 ] 2− ( x = 0-6) were obtained by reactions of [Pt 6 (CO) 12 ] 2− with Ni-clusters such as [Ni 6 (CO) 12 ] 2− , [Ni 9 (CO) 18 ] 2− and [H 2 Ni 12 (CO) 21 ] 2− , or from [Pt 9 (CO) 18 ] 2− and [Ni 6 (CO) 12 ] 2− . The Pt/Ni composition of [Pt 6− x Ni x (CO) 12 ] 2− ( x = 0-6) depended on the nature of the reagents employed and their stoichiometry. Reactions of [Pt 9 (CO) 18 ] 2− with [Ni 9 (CO) 18 ] 2− and [H 2 Ni 12 (CO) 21 ] 2− , as well as reactions of [Pt 12 (CO) 24 ] 2− with [Ni 6 (CO) 12 ] 2− , [Ni 9 (CO) 18 ] 2− and [H 2 Ni 12 (CO) 21 ] 2− , afforded [Pt 9− x Ni x (CO) 18 ] 2− ( x = 0-9) species. [Pt 6− x Ni x (CO) 12 ] 2− ( x = 1-5) were converted into [Pt 12− x Ni x (CO) 21 ] 4− ( x = 2-10) upon heating in CH 3 CN at 80 °C, with almost complete retention of the Pt/Ni composition. Reaction of [Pt 12− x Ni x (CO) 21 ] 4− ( x 8) with HBF 4 ·Et 2 O afforded the [HPt 14+ x Ni 24− x (CO) 44 ] 5− ( x 0.7) nanocluster. Finally, [Pt 19− x Ni x (CO) 22 ] 4− ( x = 2-6) could be obtained by heating [Pt 9− x Ni x (CO) 18 ] 2− ( x = 1-3) in CH 3 CN at 80 °C, or [Pt 6− x Ni x (CO) 12 ] 2− (2-4) in DMSO at 130 °C. The molecular structures of these new alloy nanoclusters have been determined by single crystal X-ray diffraction. The site preference of Pt and Ni within their metal cages has been computationally investigated. The electrochemical and IR spectroelectrochemical behavior of [Pt 19− x Ni x (CO) 22 ] 4− ( x = 3.11) has been studied and compared to the isostructural homometallic nanocluster [Pt 19 (CO) 22 ] 4− . Molecular alloy Pt-Ni nanoclusters of increasing sizes were synthesized, their structures determined by X-ray crystallography, Pt-Ni distribution computationally investigated, and the effect of Pt-Ni replacement electrochemically studied.