David Kumar Yesudoss, Bright Ngozichukwu, Ibrahima Gning, Balla D. Ngom, Abdoulaye Djire
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引用次数: 0
Abstract
This study explores the electrocatalytic nitrate reduction reaction (NO3–RR) using nitride-based two-dimensional Ti2NTx MXene (also known as MNene) synthesized via O2-assisted molten salt fluoride etching and its parent Ti2AlN MAX phase. Ti2NTx MNene achieved an ammonia (NH3) yield rate of ∼550 μmol h–1 g–1 with a Faradaic efficiency (FE) of ∼80%. Unexpectedly, the Ti2AlN MAX phase exhibited an even higher NH3 yield rate of ∼800 μmol h–1 g–1 at a comparable FE, despite its lower surface area and being traditionally considered a poor electrocatalyst. The enhanced performance of the MAX phase is likely due to −OH functionalization under alkaline conditions, leading to enhanced reaction kinetics. Postelectrolysis analyses, including Raman spectroscopy, X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS), confirmed no significant changes in crystallinity but indicated surface chemical changes. Control experiments with blank electrolytes and isotopically labelled 15NO3– substantiate that NH3 originates exclusively from nitrate reduction on the surface terminations. Time-resolved in situ spectroelectrochemical studies identified nitrite (NO2–) reduction to further intermediates as the rate-determining step. These findings not only challenge the conventional perception of MAX phases as poor electrocatalysts but also underscore the potential of nitride-based MAX and MXene materials as robust and efficient electrocatalysts for the NO3–RR.
ACS Energy Letters Energy-Renewable Energy, Sustainability and the Environment
CiteScore
31.20
自引率
5.00%
发文量
469
审稿时长
1 months
期刊介绍:
ACS Energy Letters is a monthly journal that publishes papers reporting new scientific advances in energy research. The journal focuses on topics that are of interest to scientists working in the fundamental and applied sciences. Rapid publication is a central criterion for acceptance, and the journal is known for its quick publication times, with an average of 4-6 weeks from submission to web publication in As Soon As Publishable format.
ACS Energy Letters is ranked as the number one journal in the Web of Science Electrochemistry category. It also ranks within the top 10 journals for Physical Chemistry, Energy & Fuels, and Nanoscience & Nanotechnology.
The journal offers several types of articles, including Letters, Energy Express, Perspectives, Reviews, Editorials, Viewpoints and Energy Focus. Additionally, authors have the option to submit videos that summarize or support the information presented in a Perspective or Review article, which can be highlighted on the journal's website. ACS Energy Letters is abstracted and indexed in Chemical Abstracts Service/SciFinder, EBSCO-summon, PubMed, Web of Science, Scopus and Portico.