CN102580735A - Visible light responding composite oxide photocatalyst LiAgO and preparation method thereof - Google Patents

Abstract

The invention discloses a visible light responding composite oxide photocatalyst LiAgO and a preparation method thereof. The chemical composition formula of the composite oxide photocatalyst is LiAgO. The preparation method comprises the following steps of: 1) weighing and preparing 99.9% of analytically pure chemical raw materials AgO and Li2CO3 according to the chemical composition formula LiAgO; 2) mixing the raw materials prepared in the step 1), putting the mixture in a ball milling jar, adding zirconia balls and absolute ethyl alcohol, ball-milling the materials for two-eight hours, mixing and levigating the materials, taking out and drying the powder and sieving the powder with a 200-mesh sieve; and 3) presintering the powder prepared in the step 2) at 750-850 DEG C, preserving heat for six-eight hours, naturally cooling the powder to the room temperature and then reducing the diameters of the grains to 2 mu m through grinding of a ball mill, thus obtaining the composite oxide photocatalyst LiAgO powder. The photocatalyst and the preparation method have the following beneficial effects that the preparation method is simple and is low in cost; and the prepared photocatalyst has excellent catalytic performance and has the function of decomposing harmful chemical substances and organic biomass and the bactericidal function under the irradiation of visible light.

Description

Visible light responded composite oxide photocatalyst LiAgO and preparation method thereof

Technical field

The present invention relates to a kind of visible light responded composite oxide photocatalyst LiAgO and preparation method thereof, belong to inorganic field of photocatalytic material.

Background technology

Environmental pollution is the problem that countries in the world are extremely paid close attention to, and has caused drinking water source, the industry water source quality of people's lives constantly to descend, and causes atmosphere pollution constantly to aggravate, and causes the continuous destruction of ecological environment, and human existence is constituted a serious threat.In order to address these problems, people control through the whole bag of tricks and curb environmental pollution.

From phase late 1970s, people proposed to utilize in the photochemical catalyst decomposition water with atmosphere in organic matters such as agricultural chemicals and odorant, and application examples such as self-cleaning that scribble the surface of solids of photochemical catalyst.At present; The photochemical catalyst that uses is mainly titanium dioxide, utilized titanium dioxide in the water with atmosphere in organic matters such as agricultural chemicals and odorant decompose, yet the band gap of titanium dioxide is 3.2eV; Only under than the short ultraviolet irradiation of 400nm, just can show activity; Can only almost can not utilize visible light indoor or the local work of uviol lamp is arranged, 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.Irradiation is maximum near sunshine medium wavelength visible light intensity 500nm on the face of land; Wavelength is that the energy of the visible region of 400nm-750nm approximately is 43% of a sunshine gross energy; So in order to utilize solar spectrum efficiently, searching has the attention that visible light-responded photochemical catalyst has caused people.The R and D of bismuth series photocatalyst have obtained a series of great achievements, and bismuthous compound is like BiVO ₄And Bi ₂WO ₄Be reported in and have good absorption under the visible light, and the pentavalent bismuth has equally also caused widely and used.

At present report to have visible light-responded photochemical catalyst kind still very limited, be very necessary so research and develop the new visible light-responded high efficiency photocatalyst that has.

Summary of the invention

The purpose of this invention is to provide a kind of have visible light responded composite oxide photocatalyst with and preparation method thereof.

A kind of chemical constitution formula with visible light responded composite oxide photocatalyst provided by the invention is: LiAgO.

The preparation method of above-mentioned visible light responded composite oxide photocatalyst carries out according to the following steps:

1) with 99.9% analytically pure chemical raw material AgO and Li ₂CO ₃, press LiAgO chemical formula weigh batching;

2) step (1) confected materials is mixed, puts into ball grinder, add zirconia ball and absolute ethyl alcohol, ball milling 2-8 hour, mixes levigately, take out oven dry, 200 mesh sieves;

3) powder that step (2) is made is 750-850 ℃ of pre-burning, and insulation 6-8 hour, naturally cools to room temperature, through pulverizing means such as ball mills particle diameter diminished then, reaches 2 μ m, can obtain composite oxide photocatalyst Li AgO powder.

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

The specific embodiment

To specify the present invention below:

1, in order to obtain employed composite oxides among the present invention, at first use solid-phase synthesis to prepare powder, promptly mix various oxides or carbonate according to target composition stoichiometric proportion as raw material, synthetic in air atmosphere under normal pressure again.

2, in order effectively to utilize light, the size of the photochemical catalyst among the present invention is preferably in micron level, or even nano particle, and specific area is bigger.With the oxide powder of solid-phase synthesis preparation, its particle is big and surface area is less, but can particle diameter diminished through pulverizing means such as ball mills.

3, as the simulation organic pollution, its concentration is 20mg/L with methyl orange in photocatalysis experiment of the present invention; The addition of compound oxide photocatalyst is 1g/L; Light source uses the xenon lamp of 300W, and the vessel that reactive tank uses pyrex to process obtain the light of wavelength greater than 420nm long wavelength, irradiates light catalyst then through wave filter; The catalysis time set is 120 minutes.

Embodiment 1:

1) with 99.9% analytically pure chemical raw material AgO and Li ₂CO ₃, press LiAgO chemical formula weigh batching.

2) chemical raw material that step (1) is prepared mixes, and puts into ball grinder, adds zirconia ball and absolute ethyl alcohol, and ball milling 2 hours mixes levigately, takes out oven dry, 200 mesh sieves.

3) powder that step (2) is made is 750 ℃ of pre-burnings, and is incubated 8 hours, naturally cools to room temperature, through ball mill pulverizing means particle diameter diminished then, reaches 2 μ m, can obtain composite oxide photocatalyst Li AgO powder.

Prepared photochemical catalyst under the radiation of visible light of wavelength greater than 420nm, reached 98.9% to the methyl orange clearance in 120 minutes.

Embodiment 2:

1) with 99.9% analytically pure chemical raw material AgO and Li ₂CO ₃, press LiAgO chemical formula weigh batching.

2) chemical raw material that step (1) is prepared mixes, and puts into ball grinder, adds zirconia ball and absolute ethyl alcohol, and ball milling 6 hours mixes levigately, takes out oven dry, 200 mesh sieves.

3) powder that step (2) is made is 800 ℃ of pre-burnings, and is incubated 7 hours, naturally cools to room temperature, through ball mill pulverizing means particle diameter diminished then, reaches 2 μ m, can obtain composite oxide photocatalyst Li AgO powder.

Prepared photochemical catalyst under the radiation of visible light of wavelength greater than 420nm, reached 99.5% to the methyl orange clearance in 120 minutes.

Embodiment 3:

1) with 99.9% analytically pure chemical raw material AgO and Li ₂CO ₃, press LiAgO chemical formula weigh batching.

2) chemical raw material that step (1) is prepared mixes, and puts into ball grinder, adds zirconia ball and absolute ethyl alcohol, and ball milling 8 hours mixes levigately, takes out oven dry, 200 mesh sieves.

3) powder that step (2) is made is 850 ℃ of pre-burnings, and is incubated 6 hours, naturally cools to room temperature, through ball mill pulverizing means particle diameter diminished then, reaches 2 μ m, can obtain composite oxide photocatalyst Li AgO powder.

Prepared photochemical catalyst under the radiation of visible light of wavelength greater than 420nm, reached 99.3% to the methyl orange clearance in 120 minutes.

The present invention never is limited to above embodiment.Bound, the interval value of each technological parameter (like temperature, time etc.) can both realize the present invention, do not enumerate embodiment one by one at this.

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

Claims (1)

1. composite oxides is characterized in that the chemical constitution formula of said composite oxides is: LiAgO as the application of visible light-responded photochemical catalyst;

Preparation method's step of said composite oxides is:

1) with 99.9% analytically pure chemical raw material AgO and Li ₂CO ₃, press LiAgO chemical formula weigh batching;

2) step (1) confected materials is mixed, puts into ball grinder, add zirconia ball and absolute ethyl alcohol, ball milling 2-8 hour, mixes levigately, take out oven dry, 200 mesh sieves;

3) powder that step (2) is made is 750-850 ℃ of pre-burning, and insulation 6-8 hour, naturally cools to room temperature, through ball mill pulverizing means particle diameter diminished then, reaches 2 μ m, can obtain composite oxides LiAgO powder.