Nanoclusters consist of a core of atoms that are usually protected with surface ligands, intermediate in size between single atoms and nanoparticles. Their high surface to volume ratio, unique electronic structure, and tunability makes them a great candidate as a model system for fundamental studies and application in catalysis, energy storage, and molecular electronics. In this study, we designed nanoclusters using atom-by-atom substitution to replace one of the Fe atoms in the core of [Fe6S8L6]+/2+ cluster with other transition metals. Because the core determines the overall properties of the nanocluster, this is an effective method for tuning the electronic and magnetic properties of the cluster. We synthesized nanoclusters based on the iron sulfide and nickel sulfide cluster protected with triethylphosphine ligand (PEt3) and analyzed them using high resolution mass spectrometry. Mass spectrometric analysis showed that when FeCl2 is used as a metal precursor in the synthesis singly and doubly charged cationic species are formed [Fe6S8L6]+/2+(L=PEt3). Meanwhile, using NiCl2 as a metal precursor generates singly charged [Ni3S3HL5]+ cluster with the same synthetic procedure. We examined the substitution of Ni atom to the core of [Fe6S8L6]+/2+ clusters by using 1:1 molar ratio of NiCl2 and FeCl2. Mass spectrometric analysis revealed signals corresponding to [Fe5NiS8L6]+, [Fe4Ni2S8L6]+, [Fe5NiS8L5]2+, and [Fe4Ni2S8L5]2+ species indicating that [Fe6S8L6]+/2+ cluster undergoes atom-by-atom substitution. The core of the [Ni3S3HL5]+ cluster does not undergo substitution with Fe atoms. This work increases the range of atomically precise alloy nanoclusters that have potential applications in molecular electronics, spintronics, quantum computing, and energy storage.

Synthesis of atomically precise iron sulfide clusters and their mass spectrometric analysis

Fall 2022 abstracts, posters, and presentations will launch in mid-September.

ACS Fall 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.