CN103272621A - Novel overlapping four fork type silver phosphate photocatalyst preparation method - Google Patents

Abstract

The invention provides an overlapping four fork type silver phosphate photocatalyst preparation method, which has characteristics of simpleness and easy performing, and is suitable for industrial production, wherein the prepared overlapping four fork type silver phosphate photocatalyst has characteristics of good stability, novel structure and high catalysis activity. The preparation method comprises the following specific steps: 1) adding tetrahydrofuran to water, and uniformly stirring to form a mixed solution, wherein a volume ratio of the water to the tetrahydrofuran is 4:1; 2) under a stirring condition, adding silver nitrate to the mixed solution, wherein a silver nitrate concentration in the mixed solution is 0.0468 mol/L; 3) adding phosphoric acid with a mass concentration of 85%, and adding methenamine, wherein a volume ratio of the phosphoric acid to the mixed solution is (1-1.05):1000, and a molar ratio of the methenamine to the silver nitrate is (0.5-0.85):1; and 4) stirring for 5 min, carrying out centrifugation washing, and drying at a room temperature to obtain the finished product.

Description

A kind of preparation method of novel eclipsed form four forked type silver orthophosphate photochemical catalysts

Technical field:

The present invention relates to a kind of new catalyst, belong to chemical field.

Background technology:

Japanese scientist Fujishima in 1972 etc. find TiO ₂Monocrystalline electricity level can realize photochemical catalyzing (FujishimaA, 1972), finds nano-TiO afterwards again ₂Ability with photocatalysis to degrade organic matter, TiO ₂Become the research focus in material field, but TiO ₂Energy gap be 3.2eV, its corresponding absorbing wavelength is 387.5nm, light absorption only is confined to ultraviolet region.But this part light only accounts for and shines 5% of ground solar spectrum, and TiO ₂Quantum efficiency is not higher than 28% at most, and only about 1%, utilization ratio is very low for the utilization ratio that integrates solar energy.For addressing this problem, scientist proposes two kinds of approach through constantly research: the one, traditional catalysis materials such as titanium dioxide are mixed and modification, and the 2nd, develop new catalysis material, can be to visible light-responded.Doping and the modification of titanium dioxide make certain gains, but effect is not remarkable.

On the new semiconductor light-catalyst of exploitation, the silver orthophosphate that director Ye Jinhua at Japanese material and Materials Research Institution photocatalyst material center etc. is conceived to nobody shows any interest at present.According to experimental results such as its water decomposition performance under radiation of visible light of investigation and coating decomposabilitys, found out that its photooxidation performance is tens of times of photochemical catalyst known today.Therefore silver orthophosphate is expected to become widely used novel photocatalysis agent.

The speed of silver orthophosphate catalyze and degrade organic pollutants and crystal morphology have certain relation, the speed of traditional spherical silver orthophosphate degradation of organic substances is slow, the catalytic activity of silver orthophosphate remains further to be improved, and therefore studies the easy synthetic method of silver orthophosphate and improves the emphasis that its catalytic activity becomes industry research.

Summary of the invention:

The purpose of this invention is to provide a kind of preparation method, this method is simple, is applicable to industrial production, the eclipsed form four forked type silver orthophosphate photochemical catalyst good stabilities of preparation, novel structure, catalytic activity height.

Concrete technical scheme of the present invention is as follows:

A kind of preparation method of eclipsed form four forked type silver orthophosphate photochemical catalysts, the concrete steps of this method are as follows:

1) add oxolane in water, the volume ratio of water and oxolane is 4:1, stirs, and forms mixed solution;

2) under stirring condition, in mixed solution, add silver nitrate, the concentration of silver nitrate in mixed solution is 0.0468mol/L;

3) add phosphoric acid again, add methenamine at last, the volume ratio of phosphoric acid and described mixed solution is (1～1.05): 1000, and wherein the mol ratio of methenamine and silver nitrate is (0.5～0.85): 1;

4) behind the stirring 5min, centrifuge washing at room temperature is drying to obtain.

Described phosphoric acid is that mass concentration is 85% phosphoric acid solution.

The present invention has following beneficial effect compared to existing technology:

Preparation method of the present invention is simple, preparation process does not need heating, at room temperature can carry out, the preparation process required time is short, the eclipsed form four forked type silver orthophosphate photochemical catalysts that make, novel structure, can see accompanying drawing 1,2,3,4, the photocatalytic activity height, degradable organic pollutant (as rhodamine B) speed is fast, can see accompanying drawing 5.

With non-overlapped formula four forked type silver orthophosphates, random silver orthophosphate is compared, and catalytic activity is the highest, and degradable organic pollutant is fastest, can see accompanying drawing 5.

The eclipsed form four forked type silver orthophosphate photochemical catalysts of the present invention preparation, structure is four forked types of four angle branches, and there are three branches at each angle, this structure is very novel.And the preparation method is simple, can carry out at ambient temperature, does not need the water-bath heating, can save the energy, and preparation process is simple, is suitable for suitability for industrialized production.

?

Description of drawings

Fig. 1 be the eclipsed form four forked type silver orthophosphates of embodiment one, two, three preparations under low range Electronic Speculum figure, among the figure as can be seen prepared eclipsed form four forked type silver orthophosphates be evenly to occur.

Fig. 2, the Electronic Speculum figure that the eclipsed form four forked type silver orthophosphates of 3,4th, embodiment one, two, three preparations are taken from different perspectives.

From Fig. 2,3,4, can know that each branch of finding out eclipsed form four forked type silver orthophosphates has three parallel branches, every long 5～8 microns approximately of branches.

Fig. 5 is eclipsed form four forked type silver orthophosphates, degrade the under the same conditions degraded figure of rhodamine B of non-overlapped formula four forked type silver orthophosphates, random silver orthophosphate.

 

The specific embodiment:

Embodiment one:

Get the water of 32mL, pour in the beaker, the oxolane of the 8mL that adds, stir, add the silver nitrate of 0.318g under stirring condition, the mass concentration that adds 41 μ L again is 85% phosphoric acid, the methenamine that adds 0.219g at last, stirred five minutes, the centrifuge washing precipitation, oven dry at room temperature gets final product.

 

Embodiment two:

Get the water of 32mL, pour in the beaker, the oxolane of the 8mL that adds, stir, add the silver nitrate of 0.318g under stirring condition, the mass concentration that adds 40 μ L again is 85% phosphoric acid, the methenamine that adds 0.146g at last, stirred five minutes, the centrifuge washing precipitation, oven dry at room temperature gets final product.

Embodiment three:

Get the water of 32mL, pour in the beaker, the oxolane of the 8mL that adds, stir, under stirring condition, add the silver nitrate of 0.318g, add 40 μ L mass concentrations again and be 85% phosphoric acid, the methenamine that adds 0.186g at last, stirred five minutes, the centrifuge washing precipitation, oven dry at room temperature gets final product.

?

Test case one:

Fig. 5 is eclipsed form four forked type silver orthophosphates and the non-overlapped formula four forked type silver orthophosphates of the embodiment of the invention one preparation, degrade the under the same conditions degraded comparison diagram of rhodamine B of three kinds of photochemical catalysts of random silver orthophosphate.Abscissa represent to degrade time of rhodamine B, ordinate is represented the ratio of absorbance with the initial absorbance of rhodamine B in the degradation process, the concrete operations step is to get the eclipsed form four forked type silver orthophosphates of 0.1g respectively, non-overlapped formula four forked type silver orthophosphates, random silver orthophosphate, adding 100ml concentration is in the rhodamine B of 10mg/L, and lucifuge stirs 60min, gets the 5mL reactant liquor every 3min, after centrifugation, supernatant liquor spectrophotometric instrumentation absorbance.Under radiation of visible light, stir then, got one time sample every three minutes, the centrifuging and taking supernatant liquor is surveyed absorbance, record data, drafting pattern.As seen eclipsed form four forked type silver orthophosphates and the non-overlapped formula four forked type silver orthophosphates of embodiment one preparation, random silver orthophosphate is compared, and catalytic activity is the highest, and degradable organic pollutant is fastest.

Wherein non-overlapped formula four forked type silver orthophosphates are to be that 85% phosphoric acid adds in the 80mL water with 41 μ L mass concentrations, stir and form mixed solution, under stirring condition, add the 0.425g silver nitrate, add 2.25g urea again, put into 80 degree baking oven hydro-thermals and take out after 24 hours, centrifuge washing precipitates, and dries to get final product under 60 degree conditions.

Wherein random silver orthophosphate is that sodium dihydrogen phosphate with the silver nitrate of 0.318g and 0.2g mixes to stir in the aqueous solution and makes.

Claims (2)

1. the preparation method of eclipsed form four forked type silver orthophosphate photochemical catalysts, the concrete steps of this method are as follows:

1) add oxolane in water, the volume ratio of water and oxolane is 4:1, stirs, and forms mixed solution;

2) under stirring condition, in mixed solution, add silver nitrate, the concentration of silver nitrate in mixed solution is 0.0468mol/L;

3) add phosphoric acid again, add methenamine at last, the volume ratio of phosphoric acid and described mixed solution is (1～1.05): 1000, and wherein the mol ratio of methenamine and silver nitrate is (0.5～0.85): 1;

4) behind the stirring 5min, centrifuge washing at room temperature is drying to obtain.

2. according to the preparation method of the described eclipsed form four forked type silver orthophosphate photochemical catalysts of claim 1, described phosphoric acid is that mass concentration is 85% phosphoric acid solution.

Images