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Green synthesis of carbon quantum dots embedded onto titanium dioxide nanowires for enhancing photocurrent.

ABSTRACT: The green synthesis of nanowired photocatalyst composed of carbon quantum dots-titanium hybrid-semiconductors, CQDs/TiO2, are reported. Where graphite-based CQDs with a size less than 5?nm are directly synthesized in pure water electrolyte by a one-step electrochemistry approach and subsequently electrodeposited onto as-prepared TiO2 nanowires through a voltage-driven reduction process. Electron paramagnetic resonance studies show that the CQDs can generate singlet oxygen and/or oxygen radicals to decompose the kinetic H2O2 intermediate species upon UV light illumination. With the effect of peroxidase-like CQDs, photocurrent density of CQDs/TiO2 is remarkably enhanced by a 6.4 factor when compared with that of as-prepared TiO2.

SUBMITTER: Yen YC

PROVIDER: S-EPMC5451797 | biostudies-literature | 2017 May

REPOSITORIES: biostudies-literature

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Green synthesis of carbon quantum dots embedded onto titanium dioxide nanowires for enhancing photocurrent.

Yen Yin-Cheng YC Lin Chia-Chi CC Chen Ping-Yu PY Ko Wen-Yin WY Tien Tzu-Rung TR Lin Kuan-Jiuh KJ

Royal Society open science 20170510 5

The green synthesis of nanowired photocatalyst composed of carbon quantum dots-titanium hybrid-semiconductors, CQDs/TiO<sub>2</sub>, are reported. Where graphite-based CQDs with a size less than 5 nm are directly synthesized in pure water electrolyte by a one-step electrochemistry approach and subsequently electrodeposited onto as-prepared TiO<sub>2</sub> nanowires through a voltage-driven reduction process. Electron paramagnetic resonance studies show that the CQDs can generate singlet oxygen a ...[more]

PMID: 28572996

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