Redox Modifications of Carbon Dots Shape Their Optoelectronics
Abstract
Carbon dots (CDs) are 1–10 nm scaled complex nanostructures with a wide range of applications and show unconventional photophysical behavior upon excitation. In this article, we have unveiled some of the underlying mechanisms and excited state dynamics of CDs by perturbing their interface with oxidizing and reducing agents. With no substantial alteration in size of surface-treated oxidized (^OCDs), reduced (^RCDs), and untreated CDs (^UCDs), we observe marked changes in their charge transport properties and diverse spectral signatures in singlet and triplet excited states. Fine tuning of the spectral behavior of nanomaterials is often treated as an outcome of quantum confinement of the excitons. Herein with different spectroscopic techniques along with conducting atomic force microscopy and triplet–triplet absorption, we elucidate that, not just confinement, the structural modification at the surface also dictates optoelectronic behavior by altering some properties such as energy band gap, quantum tunneling across the metal–CD–metal junction, and yield of triplet excitons.
Additional Information
© 2019 American Chemical Society. Received: August 31, 2019; Revised: October 9, 2019; Published: October 17, 2019. The authors acknowledge the Science and Engineering Research Board, Govt. of India, for the Research grant under sanction ECR/2016/002036. R.K.B. and L.M. acknowledge fellowships from IIT Patna and SERB, respectively. We greatly acknowledge the generous support from TEM division of Saha Institute of Nuclear Physics for providing the research facility for TEM measurements. The authors declare no competing financial interest.Attached Files
Supplemental Material - jp9b08289_si_001.pdf
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Additional details
- Eprint ID
- 99398
- Resolver ID
- CaltechAUTHORS:20191022-152632236
- ECR/2016/002036
- Science and Engineering Research Board (SERB)
- Indian Institute of Technology Patna
- Created
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2019-10-22Created from EPrint's datestamp field
- Updated
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2021-11-16Created from EPrint's last_modified field