CN103418370B - Visible light-responded photochemical catalyst Ca3WO6And preparation method thereof - Google Patents

Abstract

The invention discloses a kind of visible light-responded photochemical catalyst Ca₃WO₆And preparation method thereof. The chemical constitution formula of this photochemical catalyst is Ca₃WO₆. The invention also discloses the preparation method of above-mentioned material. Preparation method of the present invention is simple, cost is low, and the photochemical catalyst of preparation has good catalytic performance, has the effect of decomposing harmful chemical under radiation of visible light, and good stability, has a good application prospect.

Description

Visible light-responded photochemical catalyst Ca3WO6And preparation method thereof

Technical field

The present invention relates to a kind of visible light-responded photochemical catalyst Ca₃WO₆And preparation method thereof, belong to inorganic field of photocatalytic material.

Background technology

Along with socioeconomic development, people more and more pay close attention to for the energy and ecological environment, solve energy shortage and problem of environmental pollution and be realize sustainable development, improve people's living standard and safeguard national security in the urgent need to.

From phase late 1970s, people proposed to utilize in photochemical catalyst decomposition water and atmosphere in the organic matter such as agricultural chemicals and odorant, and scribble the application example such as self-cleaning of the surface of solids of photochemical catalyst. The principle of light-catalyzed reaction is that photochemical catalyst is after the photon having absorbed higher than its band-gap energy, hole and electronics are generated, these holes and electronics carry out respectively oxidation reaction and reduction reaction, reach the object of decomposing harmful chemical, organic-biological matter and sterilization. Photochemical catalyst has many kinds, and wherein most representative is titanium dioxide (TiO₂), utilize titanium dioxide to decompose the organic matter such as agricultural chemicals and odorant in water and in atmosphere, but the band gap of titanium dioxide is 3.2eV, only under the ultraviolet irradiation shorter than 400nm, just can show activity, can only be indoor or have a local work of uviol lamp, almost can not utilize visible ray, this has limited the use of titanium dioxide optical catalyst greatly.

Consider the practicality of photochemical catalyst in decomposing harmful substances, utilizing sunshine is indispensable as light source. Irradiate near sunshine medium wavelength visible light intensity maximum 500nm to earth's surface, wavelength is that the energy of the visible region of 400nm ~ 750nm is approximately 43% of sunshine gross energy, so for efficient utilization, the R and D of bismuth series photocatalyst have obtained a series of great achievements, and bismuthous compound is as BiVO₄、Bi₂MoO₆、Bi₂Mo₂O₉、Bi₂Mo₃O₁₂And Bi₂WO₄Be reported in and under visible ray, there is good absorption. A series of niobiums (tantalum) hydrochlorate photochemical catalyst is because the photocatalytic activity having compared with high is widely studied. For example, niobate photocatalyst Pb₃Nb₄O₁₃、BiNbO₄And Bi₂MNbO₇(M=Al, Ga, In, Y, rare earth element or Fe) etc. with niobium potassium compound oxide photocatalyst as KNbO₃、KNb₃O₈、K₄Nb₆O₁₇And K₆Nb_10.6O₃₀Deng all thering is good photocatalysis performance.

Although photocatalysis research has been carried out the several years, but at present report to have visible light-responded photochemical catalyst kind still very limited, still exist that light conversion efficiency is low, poor stability and the problem such as spectrum respective range is narrow, be very necessary so research and develop the new visible light-responded high efficiency photocatalyst that has. We are to Ba₃WO₆、Sr₃WO₆And Ca₃WO₆Deng having carried out Photocatalytic Performance Study, found that Ca₃WO₆There is excellent visible light-responded photocatalysis performance, but Sr₃WO6 and Ba₃WO₆But do not there is visible light-responded photocatalysis performance.

Summary of the invention

The object of this invention is to provide a kind of visible light-responded photochemical catalyst Ca that has₃WO₆And preparation method thereof.

The chemical constitution formula with visible light-responded photochemical catalyst the present invention relates to is: Ca₃WO₆。

Preparation method's concrete steps of above-mentioned visible light-responded photochemical catalyst are:

(1) by 99.9% analytically pure chemical raw material CaCO₃And WO₃, by Ca₃WO₆Chemical formula weigh batching.

(2) raw material step (1) being prepared mixes, and puts into ball grinder, adds zirconia ball and absolute ethyl alcohol, and ball milling 8 hours, is mixed and finely ground, and takes out and dries, and crosses 200 mesh sieves.

(3) powder step (2) being mixed is 1100 ~ 1150 DEG C of pre-burnings, and is incubated 6 hours, naturally cools to room temperature, then by ball mill pulverizing means, particle diameter diminished, and lower than 2 μ m, obtains Ca₃WO₆Powder.

Preparation method of the present invention is simple, cost is low, and the photochemical catalyst of preparation has good catalytic performance, has the effect of decomposing harmful chemical, organic-biological matter and sterilization under radiation of visible light.

Detailed description of the invention

To be specifically described the present invention below:

1, the composite oxides in order to obtain using in the present invention, first use solid-phase synthesis to prepare powder, various oxides or carbonate as raw material measured than mixing according to target constitutional chemistry, more synthetic in air atmosphere under normal pressure.

2, in order effectively to utilize light, the size of the photochemical catalyst in the present invention is preferably in micron level, or even nano particle, and specific area is larger. The oxide powder of preparing with solid-phase synthesis, its particle is compared with large and surface area is less, but can particle diameter be diminished by pulverizing means such as ball mills.

3, photocatalysis experiment of the present invention is using methyl orange as simulation organic pollution, and its concentration is 20mg/L; Photochemical catalyst Ca₃WO₆Addition be 1g/L; Light source uses the xenon lamp of 300W, and the vessel that reactive tank uses pyrex to make, obtain by wave filter the light that wavelength is greater than 420nm long wavelength, then light irradiation catalyst; Catalysis time is set as 120 minutes.

Embodiment 1:

(1) by 99.9% analytically pure chemical raw material CaCO₃And WO₃, by Ca₃WO₆Chemical formula weigh batching.

(2) raw material step (1) being prepared mixes, and puts into ball grinder, adds zirconia ball and absolute ethyl alcohol, and ball milling 8 hours, is mixed and finely ground, and takes out and dries, and crosses 200 mesh sieves.

(3) powder step (2) being mixed is 1100 DEG C of pre-burnings, and is incubated 6 hours, naturally cools to room temperature, then by ball mill pulverizing means, particle diameter diminished, and lower than 2 μ m, obtains Ca₃WO₆Powder.

Prepared photochemical catalyst, is greater than at wavelength under the radiation of visible light of 420nm, methyl orange clearance is reached to 97.2% in 120 minutes.

Embodiment 2:

(1) by 99.9% analytically pure chemical raw material CaCO₃And WO₃, by Ca₃WO₆Chemical formula weigh batching.

(2) raw material step (1) being prepared mixes, and puts into ball grinder, adds zirconia ball and absolute ethyl alcohol, and ball milling 8 hours, is mixed and finely ground, and takes out and dries, and crosses 200 mesh sieves.

(3) powder step (2) being mixed is 1130 DEG C of pre-burnings, and is incubated 6 hours, naturally cools to room temperature, then by ball mill pulverizing means, particle diameter diminished, and lower than 2 μ m, obtains Ca₃WO₆Powder.

Prepared photochemical catalyst, is greater than at wavelength under the radiation of visible light of 420nm, methyl orange clearance is reached to 98.3% in 120 minutes.

Embodiment 3:

(1) by 99.9% analytically pure chemical raw material CaCO₃And WO₃, by Ca₃WO₆Chemical formula weigh batching.

(2) raw material step (1) being prepared mixes, and puts into ball grinder, adds zirconia ball and absolute ethyl alcohol, and ball milling 8 hours, is mixed and finely ground, and takes out and dries, and crosses 200 mesh sieves.

(3) powder step (2) being mixed is 1150 DEG C of pre-burnings, and is incubated 6 hours, naturally cools to room temperature, then by ball mill pulverizing means, particle diameter diminished, and lower than 2 μ m, obtains Ca₃WO₆Powder.

Prepared photochemical catalyst, is greater than at wavelength under the radiation of visible light of 420nm, and 120min reaches 98.1% to methyl orange clearance.

The present invention is never limited to above embodiment. Bound, the interval value of each temperature can realize the present invention, do not enumerate embodiment at this.

The made photocatalyst powder of above inventive embodiments can be carried on multiple matrix surface. Matrix can be glass, pottery, active carbon or quartz sand etc., and photochemical catalyst can be carried on matrix surface with the form of film.

Claims (1)

1. tungstates, as an application for visible light-responded photochemical catalyst, is characterized in that the chemical constitution formula of described tungstates is: Ca₃WO₆；

Preparation method's concrete steps of described tungstates are:

(1) by 99.9% analytically pure chemical raw material CaCO₃And WO₃, by Ca₃WO₆Chemical formula weigh batching;

(2) raw material step (1) being prepared mixes, and puts into ball grinder, adds zirconia ball and absolute ethyl alcohol, and ball milling 8 hours, is mixed and finely ground, and takes out and dries, and crosses 200 mesh sieves;

(3) powder step (2) being mixed is 1100 ~ 1150 DEG C of pre-burnings, and is incubated 6 hours, naturally cools to room temperature, then by ball mill pulverizing means, particle diameter diminished, and lower than 2 μ m, obtains Ca₃WO₆Powder.