Fig. 1. Phase transition temperature of V₂O₅ films under undoped and different co-doped conditions

Fig. 2. Optical transmittance of V₂O₅ thin films with undoped and different tungsten-nickel co-doped V₂O₅ films

Fig. 3. The transmittance-temperature change curve of 3 # samples at wavelength of 1 310 nm

Fig. 4. XRD spectra of 3# samples and 1# samples

Fig. 5. XPS spectra of tungsten-nickel co-doped V₂O₅ films of 3# samples

Fig. 6. SEM images of tungsten-nickel co-doped V₂O₅ of 3 # samples

Fig. 7. Electrical properties of V₂O₅ films with undoped and different W and Ni doping ratios