Atomically Precise Platinum Carbonyl Nanoclusters: Synthesis, Total Structure, and Electrochemical Investigation of [Pt₂₇(CO)₃₁]^4– Displaying a Defective Structure

Abstract

The molecular Pt nanocluster [Pt 27 (CO) 31 ] 4– ( 1 4– ) was obtained by thermal decomposition of [Pt 15 (CO) 30 ] 2– in tetrahydrofuran under a H 2 atmosphere. The reaction of 1 4– with increasing amounts of HBF 4 · Et 2 O afforded the previously reported [Pt 26 (CO) 32 ] 2– ( 3 2– ) and [Pt 26 (CO) 32 ] − ( 3 – ). The new nanocluster 1 4– was characterized by IR and UV–visible spectroscopy, single-crystal X-ray diffraction, direct-current superconducting quantum interference device magnetometry, cyclic voltammetry, IR spectroelectrochemistry (IR SEC), and electrochemical impedance spectroscopy. The cluster displays a cubic-close-packed Pt 27 framework generated by the overlapping of four ABCA layers, composed of 3, 7, 11, and 6 atoms, respectively, that encapsulates a fully interstitial Pt 4 tetrahedron. One Pt atom is missing within layer 3, and this defect (vacancy) generates local deformations within layers 2 and 3. These local deformations tend to repair the defect (missing atom) and increase the number of Pt–Pt bonding contacts, minimizing the total energy. The cluster 1 4– is perfectly diamagnetic and displays a rich electrochemical behavior. Indeed, six different oxidation states have been characterized by IR SEC, unraveling the series of 1 n – ( n = 3–8) isostructural nanoclusters. Computational studies have been carried out to further support the interpretation of the experimental data.

From M6 to M12, M19 and M38 molecular alloy Pt–Ni carbonyl nanoclusters: selective growth of atomically precise heterometallic nanoclusters

“…In many cases, we observed that the voltammetric profiles of clusters are ill defined at Pt electrodes, while more resolved peaks are instead obtained at GC. 31,53 In Fig. S24 in the ESI, † the CV responses of [Pt 19−x Ni x (CO) 22 ] 4− (x = 3.11) at the two electrodes are compared.…”

Elucidation of the electronic structures of thiolate-protected gold nanoclusters by electrochemical measurements

“…These electrochemical methods have also been applied to Au NCs protected by phosphine 121–128 and stibine, 129 and to NCs based on Ag, 130–133 Cu, 134 and group 10 elements. 135–139 In the future, these electrochemical techniques are expected to reveal the electronic states of metal NCs protected by other ligands and composed of other metals. 140–144…”

“…Compared with [Au 25 (SC 6 H 13 ) 18 ] − , the oxidation and reduction peaks (O1 and R1) of [Au 25 (PPh 3 ) 10 (SC 6 H 13 ) 5 Cl 2 ] 2+ were observed at significantly These electrochemical methods have also been applied to Au NCs protected by phosphine [121][122][123][124][125][126][127][128] and stibine, 129 and to NCs based on Ag, [130][131][132][133] Cu, 134 and group 10 elements. [135][136][137][138][139] In the future, these electrochemical techniques are expected to reveal the electronic states of metal NCs protected by other ligands and composed of other metals. [140][141][142][143][144] The electrochemical gap also varies depending on the ligand, solvent, electrolyte, measurement mode, temperature, and other factors.…”

Heterometallic Ru–Ir carbonyl clusters as catalyst precursors for hydrogenation and hydrogen transfer reactions

“…[1][2][3][4][5][6][7][8][9][10][11] In this respect, molecular clusters and nanoclusters represent a link between metal complexes and metal nanoparticles. [12][13][14][15][16][17][18][19][20][21] Molecular clusters may be used in homogenous catalysis or as precursors of supported heterogeneous nanostructured catalysts. [22][23][24][25] [Ru 3 Ir(CO) 13 ] À showed high catalytic activity for the carbonylation of methanol.…”

“…1–11 In this respect, molecular clusters and nanoclusters represent a link between metal complexes and metal nanoparticles. 12–21 Molecular clusters may be used in homogenous catalysis or as precursors of supported heterogeneous nanostructured catalysts. 22–25…”