Tungsten oxide film with high photoelectric property can be prepared by hydrothermal method. Among them, experts use hydrochloric acid and heteropoly acid to co-acidify. They found that the incorporation of a small amount of heteropolyacid during the acidification process can greatly improve the photoelectric properties of the prepared WO3 film. The specific steps of this method to prepare high photoelectric WO3 film are shown as below:
More details, please visit:
http://www.tungsten-powder.com/tungsten-oxide.html
Step one: Weigh 0.7mmol Na2WO4?2H2O, dissolved in 30mL deionized water, add 6mL 3M HCl solution dropwise at room temperature, then add phosphotungstic acid, in which the molar amount of phosphotungstic acid is 5% of sodium tungstate, stir until the white precipitate no longer increases;
Step two: 1.6mmol (NH4)2C2O4 was added as a structure directing agent, and deionized water was added until the total volume of the solution was 70mL, and stirring was continued for 2 hours. The pre-cleaned FTO conductive glass was tilted into the reactor lining. The above solution was transferred to a reaction vessel, sealed, placed in a blast drying oven, and hydrothermally reacted at 150°C for 24 hours, and naturally cooled to room temperature.
Step three: The conductive glass was taken out, washed with deionized water, dried in an oven at 60°C, and calcined at 500°C for 1h to obtain a WO3 film.
