pH-Induced Surface Modification of Atomically Precise Silver Nanoclusters: An Approach for Tunable Optical and...

Area of Science:

• * Materials Science
• * Nanotechnology
• * Physical Chemistry

Background:

• * Noble metal nanoclusters (NCs) are crucial intermediaries between molecular and quantum dot regimes.
• * Understanding NCs' property evolution in diverse environments is vital for applications.
• * Ag44(MNBA)30 NCs represent a model system for studying structure-property relationships.

Purpose of the Study:

• * To experimentally investigate the influence of the chemical environment on Ag44(MNBA)30 NC properties.
• * To provide definitive evidence for environmental control over NC structural, electronic, and optical characteristics.
• * To elucidate the molecular mechanism behind environmental modulation.

Main Methods:

• * Utilized advanced spectroscopic techniques, including infrared and photoelectron spectroscopy.
• * Manipulated the chemical environment by adjusting pH levels.
• * Analyzed changes in ligand structure and NC properties.

Main Results:

• * Decisive experimental evidence shows that Ag44(MNBA)30 NC properties are tailorable via the chemical environment.
• * Observed ligand dimerization between adjacent capping molecules upon pH reduction from 13 to 7.
• * Spectroscopic data confirmed significant alterations in structural, electronic, and optical properties.

Conclusions:

• * The chemical environment, specifically pH, directly influences the properties of noble metal nanoclusters.
• * Ligand dimerization is identified as a key mechanism for property modulation in Ag44(MNBA)30 NCs.
• * This work opens avenues for designing and tuning NCs for specific applications.