The positions of the upper edge of the valence band and the lower edge of the conduction band of semiconducting materials such as TiO₂ are closely related to the values of the respective oxidation or reduction potentials. The modifications suffered by a material of this type impact on the displacements of the aforementioned bands and thus on the redox potentials. In the present work, anatase and rutile bulk systems are analyzed for how different metallic and nonmetallic dopants located substitutionally where the “@” symbol indicates that the preceding element replaces the element after it or interstitially this position in the network is indicated with the letter “i” affect these potentials. From the analysis of the modifications, consequence of the doping, it can be noted that substitutional doping of nitrogen (N) at the oxygen site (N@O) improves the reduction potential of anatase and doped with interstitial (Ni) that of rutile. On the other hand, for both polymorphs, interstitial iron (Fei) doping has the best oxidant properties, followed by doping with Fe in titanium (Ti) site (Fe@Ti). The latter also has interesting magnetic properties to facilitate the extraction of the titania from the reaction media. The other doping elements studied, vanadium, platinum, silver, carbon and fluorine only improve the oxidation potential but all to a lesser extent than iron.

中文翻译：

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选择掺杂元素改性二氧化钛还原能力的理论研究

诸如TiO _2之类的半导体材料的价带上边缘和导带下边缘的位置与各自的氧化或还原电势的值密切相关。这种材料遭受的改变会影响上述带的位移，从而影响氧化还原电势。在本工作中，分析了锐钛矿和金红石块状系统，以了解不同的金属和非金属掺杂物如何交替放置，其中“ @”符号表示前一个元素替换了其后的元素，或者在网络中，该位置间的替换用字母“我”会影响这些潜力。通过对修饰的分析以及掺杂的结果，可以注意到在氧位点（N @ O）的氮（N）的替代掺杂提高了锐钛矿的还原电位，并与金红石的间隙（Ni）掺杂。另一方面，对于这两种多态，间隙铁（Fei）掺杂具有最佳的氧化性能，其次是在钛（Ti）部位（Fe @ Ti）掺杂Fe。后者还具有令人感兴趣的磁性，以促进从反应介质中萃取二氧化钛。研究的其他掺杂元素，钒，铂，银，碳和氟仅能提高氧化电位，但都比铁少。