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化学链燃烧技术中,铁基载氧体由于成本低、环境良好、热稳定性高和机械性能优良等优点,被认为是最有前景的载氧体之一.但其反应活性相对较低,提高其反应活性成为了研究的重点.在阅读50余篇相关文章的基础上,对密度泛函理论用于铁基载氧体微观反应机理研究进行了3方面的综述:(1)铁基载氧体表面的电子结构特性及其与燃料分子(CO、H2、CH4和煤等)的氧化还原反应和形成积碳的机理;(2) Al2O3、MgO、TiO2和ZrO2等惰性载体以及Co和Pb等掺杂组分对Fe2O3反应性能的协同作用机理;(3)化学链燃烧过程中,S和Hg等杂质对铁基载氧体反应性能的影响.据此指出:密度泛函理论在煤和生物质等固体燃料化学链燃烧的研究中应用较少,以煤为主的固体燃料化学链燃烧中固-固反应机理以及灰分与Fe2O3的相互作用机制尚不清楚.此外,多组分铁基载氧体的分子结构设计及性能调控等方面有待进行深入研究.“,”In the chemical looping combustion (CLC) technologies,the Fe-based oxygen carrier is regarded as one of the most promising oxygen carriers due to its advantages such as low in cost,friendly to environments,high in thermal stability and excellent in mechanical performance etc.However,due to its relatively low reaction activity,how to enhance such an activity becomes a focus for the future studies.On the basis of more than 50 relevant papers having been read by the authors,an overview of the study in the mechanism governing the microscopic reaction of the Fe-based oxygen carrier by employing the density functional theory was given,mainly including the following three aspects:(1) the characteristics of the electronic configuration on the surface of the Fe-based oxygen carrier and the mechanism governing its oxidation and reduction reactions with the molecules of fuels (CO,H2,CH4 and coal etc.) and the carbon deposition,(2) the mechanism governing the synergetic action of such constituents as Al2O3,MgO,TiO2 and ZrO2 etc.inertial carriers as well as such constituents blended as Co and Pb etc.on the reaction performance of Fe2O3,(3) influence of such impurities as S and Hg etc.on the reaction performance of the Fe-based oxygen carrier in the process of chemical looping combustion.Finally,the problems existing in the chemical looping combustion of the Fe-based oxygen carrier were summed up.