Electrochromic performance of mixed V 2O 5–MoO 3 thin films synthesized by pulsed spray pyrolysis technique

Abstract

Mixed V 2O 5–MoO 3 thin films were deposited onto the glass and fluorine doped tin oxide (FTO) coated glass substrates, at 400 °C by pulsed spray pyrolysis technique (PSPT). Equimolar vanadium chloride (VCl 3) and ammonium molybdate aqueous solutions were mixed together in volume proportions (5–15% molybdenum) and used as a precursor solution for the deposition of mixed V 2O 5–MoO 3 thin films. The structural, morphological, optical and electrochromic properties of the films deposited at different Mo concentrations were studied. With increase in the percentage of Mo the peaks belonging to tetragonal phase of V 2O 5 eventually disappear and the (1 0 1) orthorhombic V 2O 5 phase is observed. Scanning electron microscopy (SEM) shows micro thread like reticulated morphology. The optical band gap energy varied over 2.91–2.85 eV. All the films exhibited cathodic electrochromism in lithium containing electrolyte (0.5 M LiClO 4 + propylene carbonate (PC)). The highest coloration efficiency (CE) for the V 2O 5 film with 15% MoO 3 mixing was found 35.27 cm 2 C −1.