Oxygen vacancies and their correlation with the nanomagnetism and electronic structure are crucial for applications in dilute magnetic semiconductors design applications. Here, we report on cobalt single atom-incorporated titanium dioxide (TiO2) monodispersed nanoparticles synthesized using a thermodynamic redistribution strategy. Using advanced synchrotron-based X-ray techniques and simulations, we find trivalent titanium is absent, indicating trivalent cations do not influence ferromagnetic (FM) stability. Density functional theory calculations show that the FM stability between Co2+ions is very weak. However, electron doping from additional oxygen vacancies can significantly enhance this FM stability, which explains the observed room-temperature ferromagnetism. Moreover, our calculations illustrate enhanced FM interactions between CoTi+ VOcomplexes with additional oxygen vacancies. This study explores the electronic structure and room-temperature ferromagnetism using monodispersed nanocrystallites with single-atom-incorporated TiO2nanostructures. The strategies described herein offer promise in revealing magnetism in other single-atom-incorporated nanostructures.

中文翻译：

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通过单原子 Co/TiO2 纳米结构中的氧空位控制优化铁磁稳定性


氧空位及其与纳米磁性和电子结构的相关性对于稀磁半导体设计中的应用至关重要。在这里，我们报道了使用热力学再分布策略合成的钴单原子掺入二氧化钛 （TiO2） 单分散纳米颗粒。使用先进的基于同步加速器的 X 射线技术和模拟，我们发现不存在三价钛，表明三价阳离子不会影响铁磁 （FM） 稳定性。密度泛函理论计算表明，Co2+离子之间的 FM 稳定性非常弱。然而，来自额外氧空位的电子掺杂可以显着增强这种 FM 稳定性，这解释了观察到的室温铁磁性。此外，我们的计算说明了具有额外氧空位的 CoTi + VO复合物之间增强的 FM 相互作用。本研究使用具有单原子掺入 TiO2 纳米结构的单分散纳米晶探索了电子结构和室温铁磁性。本文描述的策略为揭示其他单原子掺入的纳米结构中的磁性提供了希望。