Abstract

WO₃ – V₂O₅ composite thin films were deposited on corning 7059 glass, silicon and indium tin oxide (ITO) coated glass substrates by electron beam evaporation technique. The depositions were carried under an oxygen partial pressure of 2×10^-4 m bar at a substrate temperature of 250 ⁰C at a constant deposition rate of 0.2 nms⁻¹. The influence of V₂O₅ concentration on the structural and optical properties towards their electrochromic performance was investigated. Structural characterization (XRD) revealed that pure WO₃ thin films exhibit a crystalline orthorhombic structure which gradually transforms into an amorphous phase with increasing V₂O₅ content. Optical studies showed that the transmittance and bandgap were initially increased with the incorporation of V₂O₅ upto 10 % concentration, further more improvement of V₂O₅ concentration leads to the decrement of optical transmittance. The electrochromic performance of the composite films was found to be strongly influenced by the vanadium content indicating that V₂O₅ plays a significant role in tuning the electrochromic responsed in the WO₃ based thin films.

Biography

Dr. Kalapala Venkata Madhuri is a Professor and Head of the Department of Physics at VFSTR University, Vadlamudi, Guntur, Andhra Pradesh, India. She earned her Ph.D. in Physics from Sri Venkateswara University, Tirupati, in 2003, and subsequently completed a Postdoctoral Fellowship at the Université de Moncton, Canada, in 2005. Her research expertise lies in thin films of metal oxides and composites with applications in energy storage and gas sensing. She has published more than 35 peer-reviewed research papers, 45 conference papers and 3 book chapters, and actively contributes to the scientific community as a reviewer for international journals.