VO₂ is a promising thermochromic material for smart windows. The major challenge for its practical application is to strike a balance between a comfortable phase transition temperature (T_c) close to room temperature and high transmittance (T) in the visible light range. Herein, we investigated the phase transition behavior of Ru-doped VO₂ using first-principles calculations. The results showed that Ru-doped VO₂ can be more easily realized under O-rich conditions than under V-rich conditions. T_c is sensitive to the Ru-dopant concentration and dopant symmetry, which are related to changes in the atomic and electronic structures. Furthermore, the optical band gap for Ru_xV_1-xO₂(M) first increases and then decreases with increasing Ru content. Moreover, the switching between insulating and metallic states in Ru_xV_1-xO₂(M) can be modulated by controlling the Ru-dopant concentration, and the band gap is reduced from 0.69 eV to 0 eV with increasing Ru-dopant concentration. Additionally, Ru doping can enhance the visible and infrared light transmission (T) of VO₂ materials within their very narrow energy ranges. These results provide another way to promote the thermochromic properties of VO₂ for application in smart windows.

VO ₂是一种很有前途的智能窗户热致变色材料。对于其实际应用的主要挑战是要在一个舒适的相转变温度（之间的平衡Ť _Ç）接近室温和高透射率（Ť在可见光范围内）。在此，我们使用第一性原理计算研究了 Ru 掺杂的 VO ₂的相变行为。结果表明，Ru 掺杂的VO ₂在富O 条件下比在富V 条件下更容易实现。Ť _ç对 Ru 掺杂剂浓度和掺杂剂对称性敏感，这与原子和电子结构的变化有关。此外，Ru _x V _{1- x} O ₂ (M)的光学带隙随着Ru 含量的增加先增大后减小。此外，Ru _x V _{1- x} O ₂ (M)绝缘态和金属态之间的转换可以通过控制 Ru 掺杂浓度来调节，随着 Ru 掺杂浓度的增加，带隙从 0.69 eV 减小到 0 eV . 此外，Ru 掺杂可以增强VO ₂的可见光和红外光透射率 ( T )材料在其非常窄的能量范围内。这些结果提供了另一种方法来促进 VO ₂的热致变色特性，以应用于智能窗户。