TY - JOUR
T1 - Correlative in situ analysis of the role of oxygen on ammonia electrooxidation selectivity on NiOOH surfaces
AU - Chen, Jing
AU - Chen, Sijie
AU - Gao, Jinghao
AU - Huang, Xiaowu
AU - Stavrou, Elissaios
AU - Vogt, Charlotte
AU - Zheng, Weiran
N1 - Publisher Copyright: © 2024 Elsevier Inc.
PY - 2024/10
Y1 - 2024/10
N2 - The electrochemical ammonia oxidation reaction (AOR) offers a promising pathway for environmental remediation, energy conversion, and the production of value-added chemicals. Although NiOOH shows potential as an efficient catalyst for AOR, the underlying mechanism and the influence of the concurrent oxygen evolution reaction (OER) are not yet fully understood. Here, the AOR mechanism on NiOOH is examined, emphasizing the influence of OER and dissolved O2. Using differential electrochemical mass spectrometry (DEMS), Raman spectroelectrochemistry, UV–vis spectroelectrochemistry, and attenuated total reflection infrared reflection (ATR-IR) spectroelectrochemistry, we reveal that the NiOOH formation, AOR activity, selectivity, and deactivation as well as the reaction intermediates are significantly modulated by OER and dissolved O2. AOR on NiOOH is potential-dependent: N2 production starts with the onset of OER, while extensive NOx and NO2/3− species form at higher potentials. The OER competes with the AOR-to-N2 pathway but promotes AOR-to-NOx, where the presence of O2 mitigates OER deactivation on NiOOH. Our findings highlight the advantage of correlative in situ analysis in studying electrocatalytic processes and advance the current understanding of AOR pathways on NiOOH toward energy and environmental applications.
AB - The electrochemical ammonia oxidation reaction (AOR) offers a promising pathway for environmental remediation, energy conversion, and the production of value-added chemicals. Although NiOOH shows potential as an efficient catalyst for AOR, the underlying mechanism and the influence of the concurrent oxygen evolution reaction (OER) are not yet fully understood. Here, the AOR mechanism on NiOOH is examined, emphasizing the influence of OER and dissolved O2. Using differential electrochemical mass spectrometry (DEMS), Raman spectroelectrochemistry, UV–vis spectroelectrochemistry, and attenuated total reflection infrared reflection (ATR-IR) spectroelectrochemistry, we reveal that the NiOOH formation, AOR activity, selectivity, and deactivation as well as the reaction intermediates are significantly modulated by OER and dissolved O2. AOR on NiOOH is potential-dependent: N2 production starts with the onset of OER, while extensive NOx and NO2/3− species form at higher potentials. The OER competes with the AOR-to-N2 pathway but promotes AOR-to-NOx, where the presence of O2 mitigates OER deactivation on NiOOH. Our findings highlight the advantage of correlative in situ analysis in studying electrocatalytic processes and advance the current understanding of AOR pathways on NiOOH toward energy and environmental applications.
KW - Ammonia oxidation
KW - Dissolved oxygen
KW - NiOOH
KW - Selectivity
KW - Spectroelectrochemistry
UR - http://www.scopus.com/inward/record.url?scp=85201456932&partnerID=8YFLogxK
U2 - https://doi.org/10.1016/j.jcat.2024.115720
DO - https://doi.org/10.1016/j.jcat.2024.115720
M3 - مقالة
SN - 0021-9517
VL - 438
JO - Journal of Catalysis
JF - Journal of Catalysis
M1 - 115720
ER -