In situ synthesis of highly dispersed VO2(M) nanoparticles on glass surface for energy efficient smart windows

Fully Discrete VO2 Particulate Film with Ultra‐High Transmittance and Excellent Thermochromic Performance

“…T lum∕sol = ∫ 𝛿 lum∕sol (𝜆)T(𝜆)d𝜆∕ ∫ 𝛿 lum∕sol (𝜆)d𝜆 (1) where T(𝜆) is the transmittance, 𝛿 lum (𝜆) is the spectral luminous efficiency function for photopic vision, the AM 1.5 solar spectral irradiance is denoted as 𝛿 sol (𝜆). [25] ΔT sol was determined by ΔT sol = T sol (M phase) -T sol (R phase). Simulations: The Finite Difference Time Domain (FDTD) method was used to simulate the optical properties of the VO 2 particulate film and the VO 2 continuous film.…”

“…In the XRD pattern (Figure 1g) of the FDVP film, diffraction peaks at 2𝜃 of 27.9°and 37°match well with the standard diffraction peaks of (011) and ( 21 respectively. [22,25] The existence of V 5+ is attributed to the oxidation of the NPs surface. [26] The rather strong peak for O Si-O indicates that the high porosity in the film, leading to the detection of signals from the quartz glass substrate, [25] which is consistent with the SEM results.…”

“…[22,25] The existence of V 5+ is attributed to the oxidation of the NPs surface. [26] The rather strong peak for O Si-O indicates that the high porosity in the film, leading to the detection of signals from the quartz glass substrate, [25] which is consistent with the SEM results. The typical structure of fully discrete VO 2 NPs is further investigated by AFM.…”

“…The particle diameter is essentially distributed ≈80 nm (FigureS3f, Supporting Information). And the slight decrease in diameter from sample S2 to S5 is almost negligible due to the statistical error.According to our previous study that reveals the formation mechanism of highly dispersed VO 2 NPs by a similar solution method,[25] the porosity of the synthesized VO 2 film is significantly influenced by the solid content of VO 2+ in the precursor film. The higher the VO 2 content, the lower the initial porosity.…”

“…The XPS results obtained from the film surface are presented in Figure 1g,h. The peaks located at 515.8, 517.3, 530.1, and 532.4 eV are indexed toV 4+ , V 5+ , O 2− in VO 2 (M) (O V-O ) and O 2− in quartz glass (O Si-O ),respectively [22,25]. The existence of V 5+ is attributed to the oxidation of the NPs surface [26].…”