Effects of addition of tungsten chloride on optical properties of VO2-based thermochromic films prepared by sol–gel method

Sol-gel approaches to thermochromic vanadium dioxide coating for smart glazing application

“…Unlike other research carried out in this field, Liu et al [116] observed an unusual fall-off rate of 0.2°C per at% for W-doped films as the transition temperature decreased from 52 to 50°C, which is way smaller than expected. These results could be possibly due to different sources.…”

“…However, careful attention must be paid when employing tungsten' dopant as it seems to reduce both T lum and ΔT sol [115]. Apart from the slight discordance in Liu and coworker's experiment [116], the results of other reviewed papers [70,117] concur well with the above.…”

“…In Liu and coworker's experiment [116], there was also a considerable enhancement in ΔT IR of W-doped films. The authors described the lower transmittance change of pure VO 2 by deficient quality of crystallinity, but they failed to further justify their observations.…”

Sputtering Deposition of Sandwich-Structured V2O5/Metal (V, W)/V2O5 Multilayers for the Preparation of High-Performance Thermally Sensitive VO2 Thin Films with Selectivity of VO2 (B) and VO2 (M) Polymorph

“…The spectra of films with V middle layers of sputtering times 0 and 6 s exhibit Raman bands centered at 191, 295, 395, and 662 cm –1 , which correspond to VO 2 (B) phase structure . The distinguishable peaks (193, 221, 263, 307, 336, 386, 615, and 823 cm –1 ) of the films with V (W) middle layers of sputtering time 9 s (6 and 9 s) are associated with VO 2 monoclinic vibrational modes. ,− The narrowness and the well-defined nature of the peaks imply that the films exhibit a considerable crystalline order, in agreement with the XRD results above.…”

3D mesoporous structure assembled from monoclinic M-phase VO2 nanoflakes with enhanced thermochromic performance

“…However to get a further reduction of T c modification of morphology, 50 size, 51 defect, 52 interfacial effect, 11 Stress, 52 and phase purity 53 have been reported. Particularly doping of metals such as W, 54–57 Mo, 57,58 and Nb 57,58 were reported for the reduction of T c . Hence, synthesis materials with optimum T lum , T sol , and T c values for practical thermochromic applications are required.…”