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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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This content will become publicly available on January 9, 2026
Tuning the selectivity of bimetallic Cu electrocatalysts for CO2 reduction using atomic layer deposition
Synthesis of bimetallic electrocatalysts for CO2 reduction using atomic layer deposition results in changes in chemical state and product selectivity.
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- Award ID(s):
- 2131709
- PAR ID:
- 10628256
- Publisher / Repository:
- Royal Society of Chemistry
- Date Published:
- Journal Name:
- Chemical Communications
- Volume:
- 61
- Issue:
- 5
- ISSN:
- 1359-7345
- Page Range / eLocation ID:
- 965 to 968
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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