Site-specific substitution in atomically precise carboranethiol-protected nanoclusters and concomitant changes in
Vivek Yadav1, Arijit Jana1, Swetashree Acharya1
1DST Unit of Nanoscience (DST UNS) and Thematic Unit of Excellence (TUE), Department of Chemistry, Indian Institute of Technology, Madras, Chennai, 600036, India.
Nature Communications
|January 30, 2025
Summary
We synthesized novel anionic silver nanoclusters with unique core-shell structures. Substituting silver with gold and copper allows tuning of electronic properties for optoelectronics and catalysis.
Area of Science:
- Inorganic Chemistry
- Materials Science
- Nanotechnology
Background:
- Anionic metal nanoclusters offer tunable electronic properties.
- Core-shell structures provide unique platforms for material design.
- Ortho-carborane-1-thiol (o1-CBT) ligands enable cluster stabilization.
Purpose of the Study:
- To synthesize and characterize a novel 8e- anionic silver nanocluster, [Ag17(o1-CBT)12]3- (Ag17).
- To investigate the effects of substituting silver atoms with gold (Au) and copper (Cu) on structural and electronic properties.
- To explore the potential of these modified nanoclusters for optoelectronics and catalysis.
Main Methods:
- Synthesis of isostructural nanoclusters: [AuAg16(o1-CBT)12]3- (AuAg16), [Ag13Cu4(o1-CBT)12]3- (Ag13Cu4), and [AuAg12Cu4(o1-CBT)12]3- (AuAg12Cu4).
- Structural characterization of core-shell structures (Ag@Ag12@Ag4).
- Spectroscopic analysis (optical absorption, emission) and ultrafast optical measurements.
Main Results:
- Demonstrated a stable 8e- anionic cluster Ag17 with a unique Ag@Ag12@Ag4 core-shell structure.
- Showed preferential site-occupation: Au in the core, Cu in the tetrahedral shell.
- Observed systematic band gap expansion (2.09 eV to 2.28 eV) and altered optical properties.
- Revealed longer excited-state lifetimes in Cu-containing clusters.
Conclusions:
- Established a tunable platform for designing metal nanoclusters by heteroatom incorporation.
- Highlighted the influence of Au and Cu substitution on cluster stability, structure, and electronic properties.
- Indicated potential applications in optoelectronics and catalysis due to tailored electronic and optical characteristics.
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