VO₂@SiO₂ Nanoparticle-Based Films with Localized Surface Plasmon Resonance for Smart Windows

As an ideal thermochromic material for smart windows, vanadium dioxide (VO2(M)) has been receiving wide research interest in recent years. Enhancing the optical switching ability before and after phase transformation of the VO2(M) (i.e., enhancing the solar regulation efficiency ΔTsol while maintaining a great luminous transmittance Tlum) is the target for its application in smart windows. However, the recrystallized growth in the annealing process ruins the thermochromic performance of VO2(M) nanoparticles (NPs). Here, we report the preparation and thermochromic performance of VO2(M)@SiO2 NPs. It was found that the SiO2 shell can effectively protect VO2(M) NPs from growth in the annealing process, and the VO2(M)@SiO2 NP film exhibits an excellent thermochromic performance with ΔTsol of 18.9% and Tlum of 38% after annealing at 450 °C, because of the outstanding contribution of the enhancement and blue-shifting of the localized surface plasmon resonance. Our results provide an efficient way to synthesize VO2(M) NPs with excellent thermochromic performance for smart windows.