Nickel Hydroxide Catalyzed Bias‐free Photoelectrochemical NH<sub>3</sub> Production via Nitrate Reduction
The photoelectrochemical nitrate reduction reaction (PEC NO<sub>3</sub>RR) potentially converts nitrate, a major water pollutant, into NH<sub>3</sub>, which is an eco-friendly, next-generation energy source. However, achieving high efficiency in the PEC NO<sub>3</sub>RR has been challenging because of the need for high applied voltage and competition with the hydrogen evolution reaction (HER). In this study, a PEC NO<sub>3</sub>RR is successfully implemented that demonstrated a high NH<sub>3</sub> production rate of 2468 µg cm<sup>-2</sup> h<sup>-1</sup> (at -0.1 V vs RHE) using a c-Si photocathode with Ni foil as the catalyst. Conducting the PEC NO<sub>3</sub>RR under alkaline conditions can lead to the self-activation of the Ni surface with Ni(OH)<sub>2</sub>. Ni(OH)<sub>2</sub> can suppress the competitive HER and facilitate NO<sub>3</sub>RR, enhancing NH<sub>3</sub> production efficiency. Furthermore, a PEC NO<sub>3</sub>RR system is developed that operates without external voltage and achieved bias-free record-high solar to NH<sub>3</sub> conversion efficiency of 3.8% and an NH<sub>3</sub> production rate of 554 µg cm<sup>-2</sup> h<sup>-1</sup>.
Authors
- Kwanyong Seo (ORCID: https://orcid.org/0000-0002-8443-7933)
- Keunsu Choi (ORCID: https://orcid.org/0000-0001-7048-7297)
- Ahmad Tayyebi (ORCID: https://orcid.org/0000-0003-1971-0603)
- Ji‐Wook Jang (ORCID: https://orcid.org/0000-0003-1251-1011)
- Wonjoo Jin (ORCID: https://orcid.org/0000-0001-8415-1313)
- Je Min Yu
- Jeonghwan Park
- Seungchul Kim (ORCID: https://orcid.org/0000-0003-4356-2217)
- J. I. Jeong (ORCID: https://orcid.org/0000-0002-1050-948X)
- Hyunju Go
Institutions
- Ulsan National Institute of Science and Technology (KR)
- Korea Institute of Science and Technology (KR)
Publication Details
- Journal
- Advanced Materials
- Published
- 2025-06-22
- DOI
- https://doi.org/10.1002/adma.202506567
- Citations
- 7
- Primary Topic
- Ammonia Synthesis and Nitrogen Reduction
- Type
- article
- Field-Weighted Citation Impact
- 2.72
Funders
- National Research Foundation
- Ulsan National Institute of Science and Technology
- Ministry of Education
- Korea Institute of Science and Technology
- Korea Institute of Science and Technology Information
- Ministry of Science and ICT, South Korea
- Korea Institute of Energy Technology Evaluation and Planning