▎ 摘　　要

NOVELTY - Preparing film capable of releasing negative oxygen ions involve (i) adding nano-titanium dioxide to absolute ethanol to obtain mixed solution and dispersing to obtain nano-titanium dioxide suspension, (ii) preparing graphene oxide sol, (iii) adding graphene oxide solution to nano-titanium dioxide suspension to obtain graphene-titanium dioxide mixed solution and stirring, (iv) adding sodium citrate, polydiallyldimethylammonium chloride solution to every 100 ml graphene-titanium dioxide mixed solution and sodium dodecylbenzene sulfonate to obtain graphene mixed solution and stirring, (v) adding sodium citrate and polyvinylpyrrolidone to every 100 ml graphene-titanium dioxide mixed solution and stirring, (vi) adding sodium citrate and polyvinylpyrrolidone in every 100 ml graphene-titanium dioxide mixed solution and stirring to obtain composite solution, and (vii) dispersing composite solution to obtain composite glue solution, coating composite glue solution on glass sheet and drying. USE - The method is useful for preparing film capable of releasing negative oxygen ions (claimed). ADVANTAGE - The method solves the technical problem of low utilization efficiency of solar light by nano-titanium dioxide, uses nano-graphene conductive ability and high specific surface area to provide synergistic photosensitivity with nano-titanium dioxide, which easily accept photo-generated electrons generated by nano-titanium dioxide, inhibits the recombination of photo-generated electrons and holes, and improves photocatalytic efficiency. DETAILED DESCRIPTION - Method for preparing film capable of releasing negative oxygen ions involve (i) adding nano-titanium dioxide to absolute ethanol to obtain mixed solution and ultrasonically dispersing to obtain nano-titanium dioxide suspension, (ii) preparing graphene oxide sol, (iii) adding graphene oxide solution to nano-titanium dioxide suspension to obtain graphene-titanium dioxide mixed solution, and stirring at room temperature for 2-6 hours, (iv) adding 0.01-0.1 mol sodium citrate, 1-5 ml polydiallyldimethylammonium chloride solution to every 100 ml graphene-titanium dioxide mixed solution for first time and 0.05-0.2 mol sodium dodecylbenzene sulfonate to obtain graphene mixed solution, and magnetically stirring the graphene-titanium dioxide mixed solution in an oil bath at 60-80 degrees C for 2-5 hours, (v) adding 0.02-0.25 mol sodium citrate and 0.1-0.3 mol polyvinylpyrrolidone to every 100 ml graphene-titanium dioxide mixed solution for second time, and magnetically stirring the graphene-titanium dioxide mixed solution in an oil bath at 60-80 degrees C for 1-3 hours, (vi) adding 0.03-0.25 mol sodium citrate and 0.2-0.5 mol polyvinylpyrrolidone in every 100 ml graphene-titanium dioxide mixed solution, and magnetically stirring the graphene-titanium dioxide mixed solution in an oil bath at 60-80 degrees C for 0.5-2 hours to obtain a graphene-titanium dioxide composite solution, and (vii) dispersing the graphene-titanium dioxide composite solution in a disperser to obtain a composite glue solution, coating the composite glue solution on a glass sheet, putting the glass sheet in an oven, and drying to obtain the product, the material of the thin film comprises composite nano-particles, and the composite nano-particles comprises nano-titanium dioxide and nano-graphene coated on the surface of the nano-titanium dioxide. An INDEPENDENT CLAIM is included for a film capable of releasing negative oxygen ions, where the material of the film layer comprises composite nano-particles, and the composite nano-particles comprise nano-titanium dioxide and nano-graphene coated on the surface of the nano-titanium dioxide.