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Abstract Single‐atom catalysts have demonstrated interesting activity in a variety of applications. In this study, we prepared single Co2+sites on graphitic carbon nitride (C3N4), which was doped with carbon for enhanced activity in visible‐light CO2reduction. The synthesized materials were characterized with a variety of techniques, including microscopy, X‐ray powder diffraction, UV‐vis spectroscopy, infrared spectroscopy, photoluminescence spectroscopy, and X‐ray absorption spectroscopy. Doping C3N4with carbon was found to have profound effect on the photocatalytic activity of the single Co2+sites. At relatively low levels, carbon doping enhanced the photoresponse of C3N4in the visible region and improved charge separation upon photoactivation, thereby enhancing the photocatalytic activity. High levels of carbon doping were found to be detrimental to the photocatalytic activity of the single Co2+sites by altering the structure of C3N4and generating defect sites responsible for charge recombination.
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This content will become publicly available on June 6, 2025
Photocatalytic doping of organic semiconductors
Abstract Chemical doping is an important approach to manipulating charge-carrier concentration and transport in organic semiconductors (OSCs)1–3and ultimately enhances device performance4–7. However, conventional doping strategies often rely on the use of highly reactive (strong) dopants8–10, which are consumed during the doping process. Achieving efficient doping with weak and/or widely accessible dopants under mild conditions remains a considerable challenge. Here, we report a previously undescribed concept for the photocatalytic doping of OSCs that uses air as a weak oxidant (p-dopant) and operates at room temperature. This is a general approach that can be applied to various OSCs and photocatalysts, yielding electrical conductivities that exceed 3,000 S cm–1. We also demonstrate the successful photocatalytic reduction (n-doping) and simultaneous p-doping and n-doping of OSCs in which the organic salt used to maintain charge neutrality is the only chemical consumed. Our photocatalytic doping method offers great potential for advancing OSC doping and developing next-generation organic electronic devices.
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- Award ID(s):
- 2223922
- PAR ID:
- 10557748
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- Springer Nature
- Date Published:
- Journal Name:
- Nature
- Volume:
- 630
- Issue:
- 8015
- ISSN:
- 0028-0836
- Page Range / eLocation ID:
- 96 to 101
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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