CN103272621B - 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 again afterwards nano-TiO ₂the ability with photocatalysis to degrade organic matter, TiO ₂become the study hotspot of Material Field, but TiO ₂energy gap be 3.2eV, its corresponding absorbing wavelength is 387.5nm, light absorption is only confined to ultraviolet region.But this part light only accounts for and is irradiated to 5% of ground solar spectrum, and TiO ₂quantum efficiency, at most not higher than 28%, integrates the utilization ratio of solar energy only in 1% left and right, and utilization ratio is very low.For addressing this problem, scientist, through constantly research, proposes two kinds of approach: the one, traditional catalysis materials such as titanium dioxide are carried out to doping and modification, and the 2nd, develop new catalysis material, can be to visible light-responded.The doping and modification of titanium dioxide makes 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 the decades of times that its photooxidation performance is photochemical catalyst known today.Therefore silver orthophosphate is expected to become widely used novel photocatalyst.

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

concrete technical scheme of the present invention is as follows:

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

1) in water, add oxolane, 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, finally add methenamine, 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) stir after 5min, centrifuge washing, is at room temperature 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, 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, photocatalytic activity is high, and 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.

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

Accompanying drawing explanation

Fig. 1 be the eclipsed form four forked type silver orthophosphates of embodiment mono-, two, three preparation under low range Electronic Speculum figure, in figure, can find out that prepared eclipsed form four forked type silver orthophosphates are evenly to occur.

Fig. 2, the Electronic Speculum figure that the eclipsed form four forked type silver orthophosphates of 3,4th, embodiment, mono-, 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 approximately long 5～8 microns of branches.

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

the specific embodiment:

embodiment mono-:

Get the water of 32mL, pour in beaker, the oxolane of the 8mL adding, stir, under stirring condition, add the silver nitrate of 0.318g, then to add the mass concentration of 41 μ L be 85% phosphoric acid, the methenamine that finally adds 0.219g, stir five minutes, centrifuge washing precipitation, at room temperature dries.

embodiment bis-:

Get the water of 32mL, pour in beaker, the oxolane of the 8mL adding, stir, under stirring condition, add the silver nitrate of 0.318g, then to add the mass concentration of 40 μ L be 85% phosphoric acid, the methenamine that finally adds 0.146g, stir five minutes, centrifuge washing precipitation, at room temperature dries.

embodiment tri-:

get the water of 32mL, pour in beaker, the oxolane of the 8mL adding, stir, under stirring condition, add the silver nitrate of 0.318g, then add the phosphoric acid that 40 μ L mass concentrations are 85%, the methenamine that finally adds 0.186g, stir five minutes, centrifuge washing precipitation, at room temperature dries.

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 present invention one preparation, and three kinds of photochemical catalysts of random silver orthophosphate are the degraded comparison diagram of rhodamine B degradation under the same conditions.Abscissa represents the time of rhodamine B degradation, ordinate represents the ratio of absorbance with the initial absorbance of rhodamine B in degradation process, concrete operation step is to get respectively the eclipsed form four forked type silver orthophosphates of 0.1g, 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, every 3min, gets 5mL reactant liquor, after centrifugation, spectrophotometric instrumentation absorbance for supernatant liquor.Then under radiation of visible light, stir, get one time sample every three minutes, centrifuging and taking supernatant liquor, surveys absorbance, record data, drafting pattern.Eclipsed form four forked type silver orthophosphates and the non-overlapped formula four forked type silver orthophosphates of visible embodiment mono-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 by 41 μ L mass concentrations, to be 85% phosphoric acid adds in 80mL water, stir and form mixed solution, under stirring condition, add 0.425g silver nitrate, add again 2.25g urea, put into 80 degree baking oven hydro-thermals and take out after 24 hours, centrifuge washing precipitation is dried under 60 degree conditions.

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

Claims (1)

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

1) in water, add oxolane, 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, finally add methenamine, 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; Described phosphoric acid is that mass concentration is 85% phosphoric acid solution;

4) stir after 5min, centrifuge washing, is at room temperature drying to obtain.