Structural And Electrochromic Properties Of Molybdenum Doped Vanadium Pentoxide Thin Films By Sol-gel And Hydrothermal Synthesis

摘要

Molybdenum-doped vanadium pentoxide (Mo-doped V_2O_5) thin films with doping levels of 3-10 mol% were prepared by dip-coating technique from a stable Mo-doped V_2O_5 sol synthesized by sol-gel and hydrothermal reaction. The Mo-doped V_2O_5 films had a layered V_2O_5 matrix structure along c-axis orientation with Mo~(6+) as substitutes. Values of the inserted and extracted charge density of 21,4 and 21.3 mC·cm~(-2) and the transmittance variation (ΔT at 540 nm) between anodic (+1.0 V) and cathodic (-1.0 V) colored states of 41% were observed for the films with 5 mol% Mo~(6+) doping. Above this dopant concentration, the charge capacity and AT decreased. The enhancement of the electrochemical and electrochromic properties of the films is related to changes in the electronic properties of V_2O_5 films due to the creation of energy levels in the band gap of V_2O_5 by the Mo doping, accompanied by the reduction of the forbidden-band width and the increase of the conductivity.