Investigation into sulfur poisoning processes in Ni-based catalysts using quantum-chemical computations

Jeng-Han Wang, M. C. Lin, M. Liu

研究成果: 書貢獻/報告類型會議貢獻

摘要

Sulfur poisoning in Ni-based catalysts, one of the most critical problems in solid oxide fuel cells (SOFC), has been extensively examined at the atomic level by density functional theory (DFT). In the reversible poisoning process with atomic sulfur adsorption, the poisoning mechanism has been studied by elucidating the potential energy surface (PES) of the interfacial reactions between the sulfur contaminants (such as H2S) and Ni surfaces. The computed low reaction barriers (< 0.45 eV) and high exothermicities (< -2.51 eV) of the processes indicate that H2S can easily react and poison Ni surfaces. In the irreversible poisoning process forming nickel sulfide, the intrinsic properties of the nickel sulfide have been studied by examining its vibrational frequencies and density of states (DOS). The frequency analysis is vital to the identification with in-situ vibrational spectroscopy during the poisoning processes. The DOS analysis will be applied to understand the degradation behaviors (decrease of catalytic activity) in the sulfur-contaminated Ni catalysts. Furthermore, with thermodynamic corrections, a new computed Ni-S phase diagram precisely predicts the boundaries of the reversible and irreversible poisoning behaviors; the result agrees well with experimental observations.

原文英語
主出版物標題American Chemical Society - 235th National Meeting, Abstracts of Scientific Papers
出版狀態已發佈 - 2008 十二月 1
事件235th National Meeting of the American Chemical Society, ACS 2008 - New Orleans, LA, 美国
持續時間: 2008 四月 62008 四月 10

出版系列

名字ACS National Meeting Book of Abstracts
ISSN(列印)0065-7727

其他

其他235th National Meeting of the American Chemical Society, ACS 2008
國家美国
城市New Orleans, LA
期間08/4/608/4/10

    指紋

ASJC Scopus subject areas

  • Chemistry(all)
  • Chemical Engineering(all)

引用此

Wang, J-H., Lin, M. C., & Liu, M. (2008). Investigation into sulfur poisoning processes in Ni-based catalysts using quantum-chemical computations. 於 American Chemical Society - 235th National Meeting, Abstracts of Scientific Papers (ACS National Meeting Book of Abstracts).