Electron paramagnetic resonance, X‐ray photoelectron spectroscopy, field dependence of magnetization, X‐ray diffraction, and transmission electron microscopy are applied for the characterization of Al‐doped TiO₂ nanopowders with Fe impurities synthesized by the autoclave‐assisted hydrothermal method and annealed in vacuum or in hydrogen. The sizes of the TiO₂:(Al, Fe) nanoparticles are estimated to be about 10–20 nm. It is proposed that Al ions are presumably placed in the TiO₂ lattice in interstitial positions. Moreover, Fe³⁺ ions can occupy tetrahedral positions of Ti⁴⁺ ions as a result of Al‐doping. The results suggest that Al‐doped TiO₂ nanopowders with Fe impurities annealed in vacuum or hydrogen display both intrinsic and extrinsic ferromagnetic properties.

中文翻译：

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Al和Fe共掺杂纳米TiO2的磁学性质，电子顺磁共振和光电子能谱研究

电子顺磁共振，X射线光电子能谱，磁化强度的场依赖性，X射线衍射和透射电子显微镜用于表征Al掺杂的TiO ₂纳米粉体，该粉体通过高压釜辅助水热法合成并在Al2O3中退火而生成Fe杂质。真空或氢气中。TiO ₂：（Al，Fe）纳米粒子的大小估计约为10–20 nm。建议将铝离子置于间隙位置的TiO ₂晶格中。此外，由于铝的掺杂，Fe ³⁺离子可以占据Ti ⁴⁺离子的四面体位置。结果表明，掺铝TiO ₂ 含有Fe杂质的纳米粉在真空或氢气中退火后，既显示出固有的铁磁性特性，也显示出其固有的铁磁特性。