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Decomposition of methylamine on nitrogen atom modified Mo(100): a density functional theory study
Cun-Qin Lv1, Jian-Hong Liu, Yong Guo
1College of Chemistry and Chemical Engineering, Shanxi Datong University, Datong 037009, Shanxi Province, P. R. China. ybsy_g@263.net wangguichang@nankai.edu.cn.
Physical Chemistry Chemical Physics : PCCP
|April 13, 2012
Summary
Methylamine decomposition on modified molybdenum surfaces favors C-H bond breaking. The study maps the decomposition network, identifying a primary pathway and revealing linear relationships in reaction energetics for this catalytic process.
Area of Science:
- Surface Science
- Chemical Kinetics
- Catalysis
Background:
- Understanding methylamine decomposition is crucial for catalysis and chemical synthesis.
- The role of surface modifications, particularly nitrogen adatoms, on reaction pathways requires detailed investigation.
Purpose of the Study:
- To investigate methylamine decomposition pathways on clean and nitrogen-modified Mo(100) surfaces.
- To determine the most favorable decomposition route and associated energy barriers.
- To explore structure-activity relationships in the reaction.
Main Methods:
- Theoretical investigation of elementary reaction steps including C-N, C-H, and N-H bond scission.
- Calculation of thermochemistry and energy barriers for all elementary steps.
- Mapping of the methylamine decomposition network on N-Mo(100) and 2N-Mo(100) surfaces.
Main Results:
- Intramolecular hydrogen transfer pathway for C-N bond breaking is energetically unfavorable.
- The dominant decomposition pathway initiates with C-H bond scission, followed by sequential dehydrogenation and C-N cleavage.
- Linear relationships observed between transition state energy and final state energy for decomposition, and between barrier and valency for reverse dehydrogenation steps.
Conclusions:
- The most likely methylamine decomposition pathway on 2N-Mo(100) has been elucidated.
- Nitrogen adatoms significantly influence the decomposition mechanism.
- Observed linear relationships provide insights into the fundamental energetics of surface reactions.
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