当前位置：
X-MOL 学术
›
ACS Catal.
›
论文详情
Our official English website, www.x-mol.net, welcomes your
feedback! (Note: you will need to create a separate account there.)
Challenges in Electrocatalysis of Ammonia Oxidation on Platinum Surfaces: Discovering Reaction Pathways
ACS Catalysis ( IF 11.3 ) Pub Date : 2023-08-02 , DOI: 10.1021/acscatal.3c00677 Seiti I. Venturini 1 , Denis R. Martins de Godoi 2 , Joelma Perez 1
ACS Catalysis ( IF 11.3 ) Pub Date : 2023-08-02 , DOI: 10.1021/acscatal.3c00677 Seiti I. Venturini 1 , Denis R. Martins de Godoi 2 , Joelma Perez 1
Affiliation
|
A deep understanding of the ammonia oxidation reaction (AOR) over platinum surfaces may facilitate the use of ammonia as a carbon-free source for energy storage and conversion. Herein, using an unprecedented experimental approach of combining online electrochemical mass spectrometry (OLEMS) and ion chromatography (IC) with high-area Pt/C surfaces, many AOR products were simultaneously detected and the variation in AOR selectivity depending on the surface conditions was demonstrated. In the low-potential region of 0.40–0.82 V, the adsorbed OH– was the dominant oxygenated surface species. The AOR onset potential was 0.40 V, and the surface intermediates were NHx,ads and N2Hy,ads, which were the main precursors of N2, considered a major product. N2H4, NO, and NH2OH were considered minor products in this potential region. In the high-potential region, from 0.82 V, adsorbed O2– was the main oxygenated surface species, owing to the strong interactions between OH– and oxidized Pt. We found that NO and N2O play a key role as reaction intermediates. Another remarkable result is the detection of HN3 as a gaseous product. NO2, N2H4, and NH2OH were considered the minor products. The nitrite and nitrate detected by IC were solution-phase products of the AOR at high potentials. The real-time identification of seven gaseous products, viz., N2, NO, N2H4, NH2OH, HN3, N2O, and NO2, and two solution-phase products, NO2– and NO3–, enabled us to propose AOR mechanistic pathways, opening more possibilities for the electrochemical generation of high-value-added nitrogenated products depending on Pt surface conditions.
中文翻译：
铂表面氨氧化电催化的挑战：发现反应途径
对铂表面氨氧化反应（AOR）的深入了解可能有助于将氨用作能量存储和转化的无碳来源。在此，采用前所未有的实验方法，将在线电化学质谱（OLEMS）和离子色谱（IC）与高面积 Pt/C 表面相结合，同时检测到许多 AOR 产物，并证明了 AOR 选择性随表面条件的变化。 。在 0.40-0.82 V 的低电势区域，吸附的 OH-是主要的含氧表面物种。AOR起始电位为0.40 V，表面中间体为NH x ,ads和 N 2 H y ,ads，它们是 N 2的主要前体，被认为是主要产品。N 2 H 4、NO 和NH 2 OH 被认为是该潜在区域的次要产品。在高电位区域，从 0.82 V 开始，由于 OH -和氧化 Pt之间的强烈相互作用，吸附的 O 2–是主要的氧化表面物种。我们发现NO和N 2 O作为反应中间体发挥着关键作用。另一个显着的结果是检测到气态产物HN 3 。NO 2、N 2 H 4和NH 2OH被认为是次要产品。IC检测到的亚硝酸盐和硝酸盐是AOR在高电位下的溶液相产物。实时识别 N 2、NO、N 2 H 4、NH 2 OH、HN 3、N 2 O 和 NO 2七种气态产物以及 NO 2 –和 NO两种溶液相产物3 –，使我们能够提出 AOR 机理途径，为根据 Pt 表面条件电化学生成高附加值氮化产品提供更多可能性。
更新日期：2023-08-02
中文翻译：
铂表面氨氧化电催化的挑战：发现反应途径
对铂表面氨氧化反应（AOR）的深入了解可能有助于将氨用作能量存储和转化的无碳来源。在此，采用前所未有的实验方法，将在线电化学质谱（OLEMS）和离子色谱（IC）与高面积 Pt/C 表面相结合，同时检测到许多 AOR 产物，并证明了 AOR 选择性随表面条件的变化。 。在 0.40-0.82 V 的低电势区域，吸附的 OH-是主要的含氧表面物种。AOR起始电位为0.40 V，表面中间体为NH x ,ads和 N 2 H y ,ads，它们是 N 2的主要前体，被认为是主要产品。N 2 H 4、NO 和NH 2 OH 被认为是该潜在区域的次要产品。在高电位区域，从 0.82 V 开始，由于 OH -和氧化 Pt之间的强烈相互作用，吸附的 O 2–是主要的氧化表面物种。我们发现NO和N 2 O作为反应中间体发挥着关键作用。另一个显着的结果是检测到气态产物HN 3 。NO 2、N 2 H 4和NH 2OH被认为是次要产品。IC检测到的亚硝酸盐和硝酸盐是AOR在高电位下的溶液相产物。实时识别 N 2、NO、N 2 H 4、NH 2 OH、HN 3、N 2 O 和 NO 2七种气态产物以及 NO 2 –和 NO两种溶液相产物3 –，使我们能够提出 AOR 机理途径，为根据 Pt 表面条件电化学生成高附加值氮化产品提供更多可能性。
京公网安备 11010802027423号