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Abstract Self‐sustaining photocatalytic NO3−reduction systems could become ideal NO3−removal methods. Developing an efficient, highly active photocatalyst is the key to the photocatalytic reduction of NO3−. In this work, we present the synthesis of Ni2P‐modified Ta3N5(Ni2P/Ta3N5), TaON (Ni2P/TaON), and TiO2(Ni2P/TiO2). Starting with a 2 mM (28 g/mL NO3−−N) aqueous solution of NO3−, as made Ni2P/Ta3N5and Ni2P/TaON display as high as 79% and 61% NO3−conversion under 419 nm light within 12 h, which correspond to reaction rates per gram of 196 μmol g−1 h−1and 153 μmol g−1 h−1, respectively, and apparent quantum yields of 3–4%. Compared to 24% NO3−conversion in Ni2P/TiO2, Ni2P/Ta3N5and Ni2P/TaON exhibit higher activities due to the visible light active semiconductor (SC) substrates Ta3N5and TaON. We also discuss two possible electron migration pathways in Ni2P/semiconductor heterostructures. Our experimental results suggest one dominant electron migration pathway in these materials, namely: Photo‐generated electrons migrate from the semiconductor to co‐catalyst Ni2P, and upshift its Fermi level. The higher Fermi level provides greater driving force and allows NO3−reduction to occur on the Ni2P surface.
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Site-Controlled SiN/SiO2 Single Photon Sources Coupled to Silicon Nitride Integrated Photonics
We demonstrate an industrially scalable fabrication process for the integration of SiN/SiO2single photon emitters into on-chip nanophotonic structures with sub-diffraction limited placement accuracy.
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- Award ID(s):
- 2015025
- PAR ID:
- 10555649
- Publisher / Repository:
- Optica Publishing Group
- Date Published:
- ISBN:
- 978-1-957171-39-5
- Page Range / eLocation ID:
- FM2F.3
- Format(s):
- Medium: X
- Location:
- Charlotte, North Carolina
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1364/CLEO_FS.2024.FM2F.3
