Study On Photoelectric Properties Of Rare Earth Doped Tungsten Trioxide

Tungsten trioxide（WO₃）is a mainstream electrochromic material due to its unique extranuclear electronic structure and the diversity of tungsten valence states,which has excellent electrochromic performance,compared with other inorganic electrochromic materials,it has obvious advantages.WO₃ has the advantages of large optical modulation amplitude,long open circuit memory time and long service life,and is widely concerned and studied by researchers today.At present,research on electrochromic properties of WO₃ based films and devices have made some progress,mainly focusing on the selection of new electrolyte materials,self powered battery devices and devices with high discoloration efficiency.In this paper,rare earth europium is doped into WO₃ thin films,which adds new luminescent properties to the films,provides a theoretical basis for multifunctional WO₃ electrochromic devices,and provides a new idea for the study of the electrochromic properties of WO₃ based films.The research content of this paper is mainly divided into two parts.The first part uses RF magnetron sputtering technology to prepare WO₃ thin films.The films are prepared by changing the sputtering power,working gas environment,and working pressure respectively.The phase structure,element composition,optical properties,electrical properties,and other aspects of the prepared film samples are characterized and analyzed to find out the process parameters with the best comprehensive performance（sputtering power is 100 W,oxygen flow is 15 sccm,working pressure is 1.6Pa）,using these parameters to prepare europium doped tungsten trioxide（WO₃-Eu）composite films.In the second part of this paper,according to the theory that rare earth elements have unique luminous properties and have the potential to enhance the optical properties of semiconductor materials,europium is doped into WO₃ films to prepare WO₃ Eu composite films.The films were prepared by RF magnetron sputtering,and doped with different contents of europium（0.96%,1.89%,2.32%）by co sputtering europium oxide and WO₃ target.The element composition,phase structure,optical properties and electrochromic properties of the films were characterized,and the influence of europium doping on the photoelectric properties of the films was studied.This work not only studies the influence of europium on the structure,transmissivity,luminous performance and electrochemical performance of WO₃,but also efficiently excites europium ions through xenon lamp,a low-power light source,to achieve wide spectral band luminescence under its low-power light source,and expounds its luminous mechanism,expanding the application field of WO₃ films.In order to enhance the luminescent properties of the films,the films were annealed.It was found that after annealing,the films changed from amorphous to ordered structure,which enhanced their luminescent properties.