CN103043901B - High specific surface area and mesoporous gallium aluminium phosphate glass and preparation method thereof - Google Patents

Abstract

A high specific surface area mesoporous aluminum gallium phosphate glass and its preparation method, the composition of the glass is xGa-(1-x)Al-PO ₄ , 0<x<0.3, the preparation steps are as follows: use aluminum lactate, nitric acid Gallium and orthophosphoric acid precursors were dissolved in deionized water, and then the pH range was adjusted between 2.00 and 4.00 with ammonia water, and then gelled at room temperature. After the gel is oven-dried at 50-100°C, it is heat-treated in a muffle furnace at 400-800°C to form mesoporous glass. Tests have proved that the glass of the present invention has a glass transition temperature T _g ≥ 1000°C, a specific surface area S _BET > 300m ² /g, and an average mesopore diameter d _p = 1.0-20.0nm, and can be used as a carrier for optical gain and catalysts in the field of optoelectronics.

Description

High specific surface area mesoporous aluminum gallium phosphate glass and preparation method thereof

technical field

The invention relates to glass, in particular to a high specific surface area mesoporous aluminum gallium phosphate glass and a preparation method thereof.

Background technique

Mesoporous materials have been widely researched and applied in the fields of chemical industry, medicine, environmental protection, and nano-functional materials due to their unique properties, such as high specific surface area, large and continuously adjustable pore size, etc. The mesoporous materials prepared by the hydrothermal method are powders, which limits their optical applications, while the mesoporous materials with transparent optical properties prepared by the sol-gel method are mostly limited to the silicate system. Due to the rapid hydrolysis of silicon precursors and other factors, the synthesis of transparent mesoporous materials in non-silicon systems has always been a challenge.

Compared with the SiO ₂ system, the mesoporous material of the aluminum phosphate-based system has more active groups such as Al ³⁺ and Ga ³⁺ (P ^5- ) in the glass structure network of the system. Stronger activity has become a very popular mesoporous material system. The development of an aluminum phosphate-based glass with excellent optical uniformity is likely to be widely used in the fields of catalysts, catalyst supports, and optoelectronics.

Contents of the invention

The object of the present invention is to provide a high specific surface area mesoporous aluminum gallium phosphate glass and a preparation method thereof. Since no mesoporous glass of this component has been reported in previous inventions and researches, the mesoporous aluminum gallium phosphate glass prepared by the present invention has high glass transition temperature, high stability, high specific surface area and mesoporous aperture. The glass can be used as a carrier of optical gain and catalyst in the field of optoelectronics.

Technical solution of the present invention is as follows:

A high specific surface area mesoporous aluminum gallium phosphate glass, characterized in that: the glass composition is xGa-(1-x)Al-PO ₄ , the range of x is 0<x<0.3, the sum of aluminum and gallium and The molar ratio of phosphorus is 1:1, the specific surface area is >300m ² /g, and the typical average mesopore diameter ranges from 1.0 to 20.0nm.

The sol-gel preparation method of the above-mentioned high specific surface area aluminum gallium phosphate mesoporous glass, the method comprises the following steps:

① Prepare a mixed aqueous solution of aluminum lactate, gallium nitrate and orthophosphoric acid H ₃ PO ₄ at room temperature, select the value of x, the molar ratio of the sum of aluminum lactate, gallium nitrate and orthophosphoric acid is 1:1, aluminum lactate , Gallium nitrate and orthophosphoric acid solution concentrations range from 0.05 to 2.0mol/L;

② Use dilute ammonia water to adjust the pH of the mixed aqueous solution, and the value range of the pH is 2.00 to 4.00;

③ Stir the mixed aqueous solution evenly at room temperature;

④ Transfer the stirred mixed aqueous solution to a glass watch glass with a cover, and let it stand at room temperature for 1 to 14 days;

⑤Put the solution after standing in an oven to dry for 1-8 days at a drying temperature of 50-100°C to obtain samples;

⑥Put the sample in a crucible and sinter it in a muffle furnace, the sintering temperature ranges from 400°C to 800°C, and keep it at the sintering temperature for more than 4 hours to obtain a colorless, transparent aluminum gallium phosphate with a high specific surface area Salt mesoporous glass.

The aluminum lactate raw material is aluminum lactate or analytically pure powder used in the market, the gallium nitrate raw material is analytically pure powder, and the configuration of the orthophosphoric acid solution is diluted to 0.5-2mol/L with concentrated phosphoric acid.

The dilute ammonia water is diluted to 0.5-6 mol/L by mass ratio of 25% concentrated ammonia water.

Technical effect of the present invention is as follows:

Tests have proved that the glass has a glass transition temperature T _g ≥ 1000°C, a specific surface area S _BET > 300m ² /g, and an average mesoporous diameter d _p = 1.0-20.0nm, indicating that the glass is a mesoporous glass with a high specific surface area.

The mesoporous aluminum gallium phosphate glass prepared by the invention has high glass transition temperature, high stability, high specific surface area and mesoporous aperture. The glass can be used as a carrier of optical gain and catalyst in the field of optoelectronics.

The aluminum gallium phosphate system glass has good optical uniformity and transmittance. Compared with the SiO ₂ system, the glass structure network of this system has more active groups such as Al ³⁺ and Ga ³⁺ (P ^5- ). group, it is expected to have stronger activity in photocatalytic carrier and so on.

Description of drawings

Fig. 1 is the thermal gravimetric analysis spectrum-Thermal Gravity analysis (TG) and differential thermal analysis (Differential Thermal Analysis) (DTA) curve (implementation sample from Example 2).

Fig. 2 is the differential scanning calorimetry-DifferentialScanning Calorimetry (DSC) curve of the high specific surface area mesoporous aluminum gallium phosphate glass of the present invention (the sample of embodiment 3)

Fig. 3 is the nitrogen adsorption-desorption curve of the high specific surface area mesoporous aluminum gallium phosphate glass of the present invention (the sample of Example 1).

Fig. 4 is a mesoporous pore diameter distribution curve of the high specific surface area mesoporous alumino-gallium phosphate glass of the present invention. (sample of Example 1)

Detailed ways

The present invention will be further described below in conjunction with embodiment, but can not limit the protection scope of the present invention with this.

Example 1:

Add 0.004mol of aluminum lactate 98at% and gallium nitrate 2at% in total to 16ml of deionized water, and add 0.004mol of orthophosphoric acid solution under stirring with a magnetic stirrer. Adjust the pH to 2.40 with 0.50 mol/L dilute ammonia water, and then use a magnetic stirrer to stir for 2 hours. The stirred solution was transferred to a watch glass, allowed to stand at room temperature for 1 day, and then transferred to a 50°C oven to dry for 2 weeks. The dried sample was heat-treated in a muffle furnace with a corundum crucible, heated from room temperature to 600°C, and kept at 600°C for 6 hours to obtain a colorless and transparent mesoporous aluminum gallium phosphate glass. The specific surface area of the sample was analyzed by a Brunauer-Emmett-Teller (hereinafter referred to as BET) specific surface area measuring instrument, and the specific surface area of the sample was 515m ² /g, and the average pore diameter of the mesopores was 8.59nm.

Example 2

A total of 0.004mol of aluminum lactate 95at% and gallium nitrate 5at% were added to 24ml of deionized water, and 0.004mol of orthophosphoric acid solution was added under stirring with a magnetic stirrer. Adjust the pH to 2.8 with 1.0 mol/L dilute ammonia water, and then use a magnetic stirrer to stir for 4 hours. The stirred solution was transferred to a watch glass, allowed to stand at room temperature for 2 days, and then transferred to a 70 °C oven for 4 days to dry. The dried sample is heat-treated in a muffle furnace with a corundum crucible, heated from room temperature to 650°C, and kept at 650°C for 8 hours to obtain a colorless and transparent mesoporous aluminum gallium phosphate glass. The specific surface area of ^the sample was analyzed by BET specific surface area measuring instrument, and the average pore diameter of mesopores was 8.29nm.

Example 3

Add 0.004mol of aluminum lactate 90at% and gallium nitrate 10at% in total to 32ml of deionized water, and add 0.004mol of orthophosphoric acid solution under stirring with a magnetic stirrer. Adjust the pH to 3.0 with 1.5 mol/L dilute ammonia water, and then use a magnetic stirrer to stir for 8 hours. The stirred solution was transferred to a watch glass, allowed to stand at room temperature for 4 days, and then transferred to an 85°C oven to dry for 1 week. The dried sample was heat-treated in a muffle furnace with a corundum crucible, raised from room temperature to 700°C, and kept at 700°C for 10 hours to obtain a colorless and transparent mesoporous aluminum gallium phosphate glass. The specific surface area of the 0.1Ga-0.9Al-PO ₄ component sample analyzed by BET specific surface area measuring instrument is 343m ² /g, and the average pore diameter of mesopores is 8.24nm.

Example 4

A total of 0.004mol of aluminum lactate 99at% and gallium nitrate 1at% were added to 32ml of deionized water, and 0.004mol of orthophosphoric acid solution was added under stirring with a magnetic stirrer. Adjust the pH to 3.50 with 2.5 mol/L dilute ammonia water, and then use a magnetic stirrer to stir for 10 hours. The stirred solution was transferred to a watch glass, allowed to stand at room temperature for 8 days, and then transferred to a 100 °C oven for 14 days to dry. The dried sample was heat-treated in a muffle furnace with a corundum crucible, heated from room temperature to 800°C, and kept at 800°C for 12 hours to obtain a colorless and transparent mesoporous aluminum gallium phosphate glass. The specific surface area of 0.01Ga-0.99Al-PO ₄ is 414m ² /g, and the average pore diameter of mesopores is 4.07nm.

Example 5

A total of 0.004mol of aluminum lactate 99at% and gallium nitrate 1at% were added to 32ml of deionized water, and 0.004mol of orthophosphoric acid solution was added under stirring with a magnetic stirrer. Adjust the pH to 4.00 with 4 mol/L dilute ammonia water, and then use a magnetic stirrer to stir for 10 hours. The stirred solution was transferred to a watch glass, allowed to stand at room temperature for 8 days, and then transferred to a 100 °C oven for 14 days to dry. The dried sample was heat-treated in a muffle furnace with a corundum crucible, heated from room temperature to 800°C, and kept at 800°C for 12 hours to obtain a colorless and transparent mesoporous aluminum gallium phosphate glass. The specific surface area of 0.01Ga-0.99Al-PO ₄ is 414m ² /g and the average pore diameter of mesopores is 3.50nm according to the BET specific surface area measuring instrument.

Example 6

A total of 0.004mol of aluminum lactate 75at% and gallium nitrate 25at% were added to 32ml of deionized water, and 0.004mol of orthophosphoric acid solution was added under stirring with a magnetic stirrer. Adjust the pH to 3.00 with 4mol/L dilute ammonia water, and then stir for 4 hours with a magnetic stirrer. The stirred solution was transferred to a watch glass, allowed to stand at room temperature for 1 day, and then transferred to a 50 °C oven for 2 days to dry. The dried sample was heat-treated in a muffle furnace with a corundum crucible, heated from room temperature to 600°C, and kept at 600°C for 6 hours to obtain a colorless and transparent mesoporous aluminum gallium phosphate glass. Its specific surface area is 320m ² /g and the average pore diameter of mesopores is 15.23nm according to the BET specific surface area measuring instrument.

Example 7

Add aluminum lactate 70at% and gallium nitrate 30at% total 0.004mol into 20ml deionized water, add 0.004mol orthophosphoric acid solution under magnetic stirrer stirring. Adjust the pH to 3.00 with 4mol/L dilute ammonia water, and then stir for 4 hours with a magnetic stirrer. The stirred solution was transferred to a watch glass, allowed to stand at room temperature for 1 day, and then transferred to a 50 °C oven for 2 days to dry. The dried sample was heat-treated in a muffle furnace with a corundum crucible, heated from room temperature to 450°C, and kept at 450°C for 12 hours to obtain a colorless and transparent mesoporous aluminum gallium phosphate glass. The specific surface area is 308m ² /g and the average pore diameter of mesopores is 16.86nm according to the BET specific surface area measuring instrument.

Tests prove that the glass of the present invention has a glass transition temperature T _g ≥ 1000°C, a specific surface area S _BET > 300 m ² /g, and an average mesopore diameter d _p = 1.0-20.0 nm. The mesoporous aluminum gallium phosphate glass prepared by the invention has high glass transition temperature, high stability, high specific surface area and mesoporous aperture. The glass can be used as a carrier of optical gain and catalyst in the field of optoelectronics.

The above-mentioned methods can be listed in many ways, as long as it is within the scope involved in this scheme, which includes the concentration range of the precursor solution, the adjusted pH range, the drying temperature range and the sintering temperature range, high specific surface area mesoporous aluminum gallium can be prepared. Phosphate glass.

Claims (4)

1. a high specific surface area and mesoporous gallium aluminium phosphate glass, is characterized in that: this glass consists of xGa-(1-x) Al-PO ₄, the span of x is 0<x<0.3, and aluminium, gallium add up to and the mol ratio of phosphorus is 1:1, specific surface area >300m ²/ g, the scope 1.0 ~ 20.0nm of typical average mesopore diameter.

2. the sol-gel process for preparing of high specific surface area and mesoporous gallium aluminium phosphate glass according to claim 1, is characterized in that the method comprises the steps:

1. Aluctyl, gallium nitrate and ortho-phosphoric acid H is at room temperature configured ₃pO ₄mixed aqueous solution, the value of selected x, described Aluctyl, gallium nitrate sum and ortho-phosphoric mol ratio are 1:1, and described Aluctyl, gallium nitrate and ortho-phosphoric strength of solution scope are 0.05 ~ 2.0mol/L;

2. adopt weak ammonia to regulate the pH of this mixed aqueous solution, the span of this pH is 2.00 ~ 4.00;

3. by described mixed aqueous solution at room temperature, stir;

4. the mixed aqueous solution after stirring is transferred in glass surface ware with cover, left at room temperature 1 ~ 14 day;

5. the solution after leaving standstill is put into baking oven dry 1 ~ 8 day, drying temperature is 50 ~ 100 DEG C and obtains sample;

6. described sample is placed in crucible, sinters in retort furnace, sintering range is 400 DEG C ~ 800 DEG C, and is incubated more than 4 hours at a sintering temperature, obtains the mesoporous glass of gallium aluminium phosphoric acid salt of water white transparency high-specific surface area.

3. the sol-gel process for preparing of high specific surface area and mesoporous gallium aluminium phosphate glass according to claim 2, it is characterized in that, Aluctyl raw material adopts analytical pure powder, and gallium nitrate raw material adopts analytical pure powder, and the configuration of ortho-phosphoric acid solution adopts strong phosphoric acid to be diluted to 0.5 ~ 2mol/L.

4. the sol-gel process for preparing of high specific surface area and mesoporous gallium aluminium phosphate glass according to claim 2, is characterized in that, described weak ammonia adopts the strong aqua of mass ratio 25% to be diluted to 0.5 ~ 6mol/L.