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Photoluminescence investigations of sulfur quantum dots synthesized by a bubbling-assisted strategy.

ABSTRACT: Sulfur quantum dots (S-dots) emerge as promising luminescent materials owing to their remarkable optical properties. However, the mechanisms of their formation and photoluminescence remain concealed. We reveal these mechanisms by the bubbling-assisted synthesis and spectroscopic study of S-dots formed from sulfur ions produced by the alkaline oxidation of bulk sulfur under the passivation of PEG. The emission colour of the S-dots depends on the size, explained by the quantum confinement effect. The dots' luminescent quantum efficiency is strongly affected by the surface sulfur species, which is optimized by the proper surface oxidation. The simple synthesis, excellent luminescence properties, and metal-free nature attract S-dots to optoelectronic and electroluminescence applications.

SUBMITTER: Liu S

PROVIDER: S-EPMC9417840 | biostudies-literature | 2021 Jul

REPOSITORIES: biostudies-literature

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Photoluminescence investigations of sulfur quantum dots synthesized by a bubbling-assisted strategy.

Liu Shuo S Wang Henggang H Feng Anrui A Chang Jianyu J Zhang Chuanchuan C Shi Yu-E YE Zhai Yongqing Y Biju Vasudevanpillai V Wang Zhenguang Z

Nanoscale advances 20210621 14

Sulfur quantum dots (S-dots) emerge as promising luminescent materials owing to their remarkable optical properties. However, the mechanisms of their formation and photoluminescence remain concealed. We reveal these mechanisms by the bubbling-assisted synthesis and spectroscopic study of S-dots formed from sulfur ions produced by the alkaline oxidation of bulk sulfur under the passivation of PEG. The emission colour of the S-dots depends on the size, explained by the quantum confinement effect. ...[more]

PMID: 36132827

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