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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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This content will become publicly available on October 9, 2026
Defect compensation as a strategic approach to enhance photocatalytic water splitting performance of SrTiO 3
Abstract Determining suitable dopants with optimized doping concentration is critical to design efficient water splitting photocatalysts. However, there is currently a lack of fundamental knowledge to guide this process. Herein, we examine the impact of Al3+, Mg2+, and Ga3+on the photocatalytic performance of SrTiO3and propose a defect compensation model to understand the doping effect. Doped SrTiO3crystals were grown hydrothermally and treated in molten SrCl2. The hydrogen production rates from 50 catalysts produced in this way were measured with a high‐throughput parallelized and automated photochemical reactor (PAPCR). The investigation revealed that all three dopants significantly enhance the photocatalytic reactivity. According to Brouwer diagrams computed using available reaction constants, the optimum reactivity is achieved when the concentration of acceptor dopants fully compensates the oxygen vacancy donors. The improved reactivity can be attributed to the reduction in free electron concentration, resulting in a space charge layer that is 1000 times longer. Consequently, this situation enhances the number of photogenerated charge carriers capable of being separated by the band bending and transported to the surface.
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- Award ID(s):
- 2016267
- PAR ID:
- 10643671
- Publisher / Repository:
- J. Wiley
- Date Published:
- Journal Name:
- Journal of the American Ceramic Society
- ISSN:
- 0002-7820
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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