Effect of ZnO dopant on V2O5:ZnO films electrochromic properties

Due to its unique physical and chemical properties, vanadium pentoxide has become a popular material for electrochromic devices, and using doping with other transition metals can enhance its overall performance. Therefore, the peroxovanadate sol-gel method was used to produce ZnO-doped V2O5 thin films. The results of this work show how ZnO doping affected the electrochromic and structural characteristics of thin films of V2O5. The main finding was that adding ZnO to the V2O5 films improved their cyclic stability and reversibility. Besides that, the incorporation of the dopant resulted in a mixture of crystalline phases, according to the X-ray diffraction. The charge density has increased from 28.79 for undoped to 41.68 mC/cm2 for doped films. The UV–Vis transmittance values between bleached and colored states - ΔT at 633 nm - changed from 14.4 to 55.5% for undoped and doped films, respectively. The roughness (root mean square, RMS) of the film remained the same, i.e., 23.5 ± 4.3 for undoped to 23.8 ± 5.1 nm for doped, as revealed by atomic force microscopy. Finally, the doping of V2O5 with ZnO improved the electrochemical and electrochromic characteristics of these new films, making them promising candidates for electrochromic device applications. © 2023 Elsevier B.V.