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Physical Origin of Dual-Emission of Au-Ag Bimetallic Nanoclusters.

ABSTRACT: On the origin of photoluminescence of noble metal NCs, there are always hot debates: metal-centered quantum-size confinement effect VS ligand-centered surface state mechanism. Herein, we provided solid evidence that structural water molecules (SWs) confined in the nanocavity formed by surface-protective-ligand packing on the metal NCs are the real luminescent emitters of Au-Ag bimetal NCs. The Ag cation mediated Au-Ag bimetal NCs exhibit the unique pH-dependent dual-emission characteristic with larger Stokes shift up to 200 nm, which could be used as potential ratiometric nanosensors for pH detection. Our results provide a completely new insight on the understanding of the origin of photoluminescence of metal NCs, which elucidates the abnormal PL emission phenomena, including solvent effect, pH-dependent behavior, surface ligand effect, multiple emitter centers, and large-Stoke's shift.

SUBMITTER: Peng B

PROVIDER: S-EPMC8503609 | biostudies-literature | 2021

REPOSITORIES: biostudies-literature

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Physical Origin of Dual-Emission of Au-Ag Bimetallic Nanoclusters.

Peng Bo B Zheng Liu-Xi LX Wang Pan-Yue PY Zhou Jia-Feng JF Ding Meng M Sun Hao-Di HD Shan Bing-Qian BQ Zhang Kun K

Frontiers in chemistry 20210927

On the origin of photoluminescence of noble metal NCs, there are always hot debates: metal-centered quantum-size confinement effect VS ligand-centered surface state mechanism. Herein, we provided solid evidence that structural water molecules (SWs) confined in the nanocavity formed by surface-protective-ligand packing on the metal NCs are the real luminescent emitters of Au-Ag bimetal NCs. The Ag cation mediated Au-Ag bimetal NCs exhibit the unique pH-dependent dual-emission characteristic with ...[more]

PMID: 34646815

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