452results about How to "Reduced band gap" patented technology

The invention discloses a preparation method of a photocatalytic ultrafilter membrane material with visible light activity. The method comprises the following steps: 1, preparing N-TiO2 powder; 2, preparing N-TiO2 / GO particles; 3, preparing an ultrafilter membrane; and 4, producing an ultrafilter membrane with the surface loaded with N-TiO2 / GO: processing the N-TiO2 / GO particles to prepare an N-TiO2 / GO dispersion, tiling the ultrafilter membrane on a suction filtration device, pouring the N-TiO2 / GO dispersion, carrying out vacuum pumping, and airing the obtained membrane to obtain the ultrafilter membrane with the surface loaded with N-TiO2 / GO. The photocatalytic material with the advantages of visible light activity, hydrophilic property and difficulty in loss of nano-particles is obtained through the preparation method of the photocatalytic ultrafilter membrane material with visible light activity.

The invention relates to a monodispersed spherical titanium dioxide core-shell structure composite material and a preparation method thereof. The monodispersed spherical titanium dioxide core-shell structure composite material comprises an inner core formed by monodispersed carbon spheres and a titanium dioxide shell layer covering the inner core, wherein noble metal is doped in the titanium dioxide shell layer.

The invention discloses a preparation method of doped nano-titanium dioxide with visible-light activity and a preparation method of polishing emulsion of a visible light photocatalytic photocatalyst. The silver-nitrogen co-doping is carried out on titanium dioxide nano particles, so that the forbidden bandwidth of the photocatalyst is reduced by the doped nano-TiO2 with the visible-light activity; furthermore, the photocatalyst material is compounded with oil polish for the first time, so that the polishing emulsion of the visible light photocatalytic photocatalyst having a function of removing organic pollutant in a photocatalytic way and the polishing decontamination capability can be prepared; the polishing emulsion does not have pungent smell and is free from secondary pollution; the methods provided by the invention are simple and easy to implement.

The invention provides a preparation method of a BiOCl nanometer photocatalyst, the prepared photocatalyst, and application of the prepared photocatalyst. The method comprises the following steps: (1) dissolving bismuth nitrate and sodium carboxymethylcellulose into water, stirring evenly to obtain a bismuth containing mixed solution, wherein the mass ratio of the bismuth nitrate to the sodium carboxymethylcellulose is (0.3-5):1, the viscosity of the sodium carboxymethylcellulose is 200-500 mPas; (2) dropwise adding a chloride solution into the mixed solution obtained in the step (1), stirring evenly to obtain a bismuth containing precursor solution; (3) regulating the pH value of the bismuth containing precursor solution obtained in the step (2) to 5.0-6.5, stirring evenly to form a reactant; (4) enabling the reactant to react for 24-30 hours at the temperature of 150-160 DEG C to obtain a precipitate; (5) washing and drying the precipitate obtained in the step (4) to obtain a BiOCl powder. The provided preparation method is simple, green and pollution-free, the preparation cycle is short, the cost is low, and the property and the stability of the prepared photocatalyst are excellent.

The invention relates to the field of titanium dioxide photocatalyst, in particular to the field of a film loading type iron nitrogen co-doping titanium dioxide photocatalyst. The invention provides a preparation method for a flexible carrier (LDPE) film loading type iron nitrogen co-doping TiO2 catalyst. The catalyst contains an active constituent and a carrier. The iron nitrogen co-doping titanium dioxide, as the active constituent of the loading catalyst, is loaded on a low density polyethylene film carrier. The preparation method for photocatalyst is the sol-gel method. The loading method for catalyst is the dipping sediment-thermal treatment method. The invention has excellent photocatalysis oxidability under visible lights, has simple preparation process and can be reused.

The invention discloses a method for preparing iron-doped nitrogen-doped nanometer titanium dioxide powder. The preparation method comprises the steps of preparing titanium tetrachloride raw material to be hydrosol, aging the hydrosol, adding water for dilution, doping water-soluble iron salt, raising temperature to hydrolyze sol and produce precipitate, filtering the precipitate, using water to wash the precipitate, drying the precipitate, obtaining iron-doped nanometer titanium dioxide powder, mixing and then ball-milling nitrogen salt and the iron-doped nanometer titanium dioxide powder, calcining the ball-milled powder, and cooling the powder to obtain the iron-doped nitrogen-doped nanometer titanium dioxide powder. The preparation method combines a chemical method with a physical method so as to allow iron to uniformly enter a crystal lattice structure of titanium dioxide on the one hand, and to uniformly distribute nitrogen in surface layers of nanometer particles, particularly non-crystallization layers on the other hand. The iron-doped nitrogen-doped nanometer titanium dioxide powder can improve the photocatalysis efficiency of titanium dioxide on the one hand, and can expand the photoresponse wavelength of titanium dioxide so as to greatly improve photocatalysis properties.

The invention discloses a rare earth elements co-doped indium sulfide material as well as a preparation method and application thereof. The indium sulfide material is formed in a way that rare earth elements Yb and Tm are co-doped with indium sulfide. The preparation method comprises the following steps: dissolving an indium source, an ytterbium source, a thulium source and a sulfur source into water, so as to obtain mixed solution; performing a hydrothermal reaction on the obtained mixed solution; and performing washing and vacuum drying, so as to obtain the rare earth elements co-doped indium sulfide material. The rare earth elements co-doped indium sulfide material has the advantages of narrow energy gap, wide spectral response characteristic, and high photogenerated charge separation efficiency; and the preparation method has the advantages of being simple in process, strong in operability and low in production cost, being environment-friendly and pollution-free. When the rare earth elements co-doped indium sulfide material is used for treating heavy metal wastewater or dye wastewater, the indium sulfide material has the advantages of being short in reaction time in a treatmentprocess, high in utilization efficiency of solar energy, high in photocatalytic conversion efficiency, convenient in operation and the like, and therefore, the indium sulfide material can be widely applied to elimination of toxicity and harmless treatment for heavy metals and dyes in the wastewater and has great importance.