摘要
水煤气变换是一重要的制备氢气的反应,采用密度泛函理论(DFT),对水煤气变换反应在Fe3O4(111)面上的催化反应作了深入研究.结果表明:氧化还原机理的活化能明显高于结合机理的活化能,中间步骤应以结合机理进行;氢原子结合生成氢气为整个反应的速控步骤,理论计算其活化能与水煤气变换实验数据一致,高达1.29 eV,还对迄今有关水煤气变换机理研究中的各种实验现象作了合理的解释,并对Fe3O4(111)催化剂的改性设计作了讨论.
Water gas shift （WGS） reaction is of great importance for industrial hydrogen production. Using density functional theory calculation, we systematically investigated the catalytic processes of WGS on Fe3O4（111） surface. Our calculations indicate that the activation barrier of the redox mechanism is much larger than that of the associative mechanism, suggesting the intermediates of WGS prefer to undergo the associative pathway. H atoms recombination towards H2 is the rate determining step with an activation barrier of 1.29 eV, in good agreement with reported experimental values. The results provide rational explanations to the experimental phenomena of WGS reaction, and the improvement of Fe3O4（111） catalyst was also discussed.
出处
《化学学报》
SCIE
CAS
CSCD
北大核心
2011年第4期393-398,共6页
Acta Chimica Sinica
基金
国家自然科学基金(No.20973159)资助项目
关键词
水煤气变换
四氧化三铁
密度泛函理论
机理
water gas shift reaction
Fe3O4
density functional theory
mechanism
