Formation mechanisms of Fe(3-x)Sn(x)O(4) by a chemical vapor transport (CVT) process.
Formation mechanisms of Fe(3-x)Sn(x)O(4) by a chemical vapor transport (CVT) process.
复制标题
化学气相传输 (CVT) 过程形成 Fe3-xSnxO4 的机制
DOI：
10.1038/srep43463
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发表时间：
2017-03-06
影响因子：
4.6
通讯作者：
Jiang T
中科院分区：
文献类型：
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作者：
Su Z;Zhang Y;Liu B;Chen Y;Li G;Jiang T
我们之前的研究报道了在900 ~ 1100℃CO-CO2气氛下，对SnO2和Fe3O4进行焙烧，容易形成Fe-Sn尖晶石（Fe3−xSnxO4）。然而，铁锡尖晶石的形成过程尚不清楚，缺乏对其形成机理的理论研究。本文采用XRD、VSM、SEM-EDS、XPS等方法对CO-CO2气氛下SnO2与Fe3O4的反应机理进行了研究。结果表明，Fe3−xSnxO4的形成可分为四个步骤：SnO2还原成固相SnO、气态SnO挥发、气态SnO在Fe3O4表面吸附、SnO与Fe3O4发生氧化还原反应。在焙烧过程中，Fe3O4中的部分Fe3+被气态SnO还原为Fe2+，同时Sn2+被氧化为Sn4+，进入Fe3−xSnxO4中。SnO2与Fe3O4的反应可以概括为Fe3O4 + xSnO(g)→Fe3−xSnxO4 （x = 0-1.0）。
Our former study reported that Fe-Sn spinel (Fe3−xSnxO4) was easily formed when SnO2 and Fe3O4 were roasted under CO-CO2 atmosphere at 900–1100 °C. However, the formation procedure is still unclear and there is a lack of theoretical research on the formation mechanism of the Fe-Sn spinel. In this work, the reaction mechanisms between SnO2 and Fe3O4 under CO-CO2 atmosphere were determined using XRD, VSM, SEM-EDS, XPS, etc. The results indicated that the formation of Fe3−xSnxO4 could be divided into four steps: reduction of SnO2 to solid phase SnO, volatilization of gaseous SnO, adsorption of gaseous SnO on the surface of Fe3O4, and redox reaction between SnO and Fe3O4. During the roasting process, part of Fe3+ in Fe3O4 was reduced to Fe2+ by gaseous SnO, and meanwhile Sn2+ was oxidized to Sn4+ and entered into Fe3−xSnxO4. The reaction between SnO2 and Fe3O4 could be summarized as Fe3O4 + xSnO(g) → Fe3−xSnxO4 (x = 0–1.0).