Vanadium Dioxide Nanoparticle-based Thermochromic Smart Coating: High Luminous Transmittance, Excellent Solar Regulation Efficiency, and Near Room Temperature Phase Transition

摘要

An annealing-assisted preparation method of well-crystallized VxW1-xO2(M)@SiO2 core shell nanoparticles for VO2-based thermochromic smart coatings (VTSC) is presented. The additional annealing process reduces the defect density of the initial hydrothermally prepared VxW1-xO2(M) nanoparticles and enhances their crystallinity so that the thermochromic film based on VxW1-xO2(M)@SiO2 nanoparticles can exhibit outstanding thermochromic performance with balanced solar regulation efficiency (Delta T-sol) of 17.3%, luminous transmittance (T-lum) up to 52.2%, and critical phase transition temperature (T-c) around 40.4 degrees C, which is very promising for practical application. Furthermore, it makes great progress in reducing T-c of VTSC to near room temperature (25.2 degrees C) and simutaneously maintaining excellent optical properties (Delta T-sol = 14.7% and T-lum = 50.6%), Such thermochromic performance is good enough to make VTSC applicable to practical architecture.