Pd/SiO2@Al2O3 (palladium/silicon dioxide@aluminum oxide) nanocrystalline material and preparation method and application thereof

A nanocrystalline material and nanocrystalline technology, applied in chemical instruments and methods, fuels, gas fuels, etc., can solve problems such as restrictions on popularization and application, achieve good application prospects, and improve the thermal stability of high-temperature catalytic reactions

CN107855123AActive Publication Date: 2018-03-30UNIV OF SCI & TECH OF CHINA
7 Cites 8 Cited by

Patent Information

Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
Publication Date
2018-03-30

Smart Images

  • Figure 1
    Figure 1
  • Figure 2
    Figure 2
  • Figure 3
    Figure 3
Patent Text Reader

Abstract

The invention provides a Pd / SiO2@Al2O3 (palladium / silicon dioxide@aluminum oxide) nanocrystalline material. The Pd / SiO2@Al2O3 nanocrystalline material comprises Pd / SiO2 nanocrystalline and an Al2O3 layer, wherein the surface of the Pd / SiO2 nanocrystalline is coated with the Al2O3 layer; the Pd / SiO2 nanocrystalline consists of Pd nanocrystalline and SiO2; the Pd nanocrystalline is compounded to thesurface of the SiO2. The Pd / SiO2@Al2O3 nanocrystalline material has the advantages that a core-shell type material with Al2O3 coated Pd / SiO2 nanocrystalline is provided; the Pd / SiO2 nanocrystalline is internally coated by the Al2O3 layer with certain thickness; the Pd / SiO2@Al2O3 nanocrystalline material is applied to high-temperature combustion reaction of alkane, the low-temperature catalyzing property in terms of alkane combustion is higher, and the high-temperature thermal stability is better; by adjusting the shape of Pd, and changing the property of the Pd / SiO2@Al2O3 nanocrystalline material, the important guidance meaning is provided in the design aspects of the catalyst in the field of high temperature combustion of alkane.
Need to check novelty before this filing date? Find Prior Art

Description

technical field

[0001] The invention belongs to the technical field of metal catalysts, and relates to a composite palladium nanocrystal material and its preparation method and application, in particular to a Pd / SiO 2 @Al 2 o 3 Nanocrystalline materials and their preparation methods and applications. Background technique

[0002] Catalyst is one of the most common substances in chemical reactions. It refers to substances that can change the chemical reaction rate of reactants in chemical reactions without changing the chemical balance, and their quality and chemical properties have not changed before and after the chemical reaction. It is called a catalyst, and its relationship with the reaction system is like the relationship between a lock and a key, with a high degree of selectivity. According to statistics, more than 90% of industrial processes use catalysts, such as chemical, petrochemical, biochemical, and environmental protection. Therefore, the research on cataly...

Examples

preparation example Construction

[0073] The present invention also provides a Pd / SiO 2 @Al 2 o 3 The preparation method of nanocrystalline material comprises the following steps:

[0074] A) After mixing polyvinylpyrrolidone, reducing agent, auxiliary agent, nano-silica, water and palladium source compound for reaction, Pd / SiO is obtained 2Nanocrystalline;

[0075] B) Pd / SiO obtained by combining trimethylaluminum and water in the above steps 2 After deposition on the nanocrystalline surface, Al 2 o 3 Coated Pd / SiO 2 nanocrystalline materials;

[0076] C) the Al obtained by the above steps 2 o 3 Coated Pd / SiO 2 After the nanocrystalline materials were heat-treated in oxidizing and reducing atmospheres, Pd / SiO 2 @Al 2 o 3 nanocrystalline material.

[0077] The present invention is to Al in the above-mentioned preparation method 2 o 3 Coated Pd / SiO 2 The selection and requirements of nanocrystalline materials, as well as the corresponding optimization principles, are similar to those of the afo...

Embodiment 1

[0126] Cubic Pd{100} / SiO 2 Synthesis of Nanocrystals

[0127] Take 105mg of polyvinylpyrrolidone (Mw=55000), 60mg of ascorbic acid, 75mg of KBr, and 141mg of KCl and dissolve them in 7ml of ultrapure water in a single-necked flask with a capacity of 25ml, keep the temperature in an oil bath at 80°C for 10min, and then add 1ml of SiO 2 Suspension (150mg / ml) was kept at constant temperature for 5 minutes, and 3ml of 65mmol / L Na was added again 2 PdCl 4 The aqueous solution reacted for 3h. Finally, centrifuge washing and vacuum drying at room temperature for 24 hours, and then the three-dimensional Pd{100} / SiO with PVP protective agent on the surface was obtained. 2 Nanocrystalline.

[0128] The cubic Pd{100} prepared in Example 1 of the present invention was characterized.

[0129] see figure 1 , figure 1 TEM image of cubic Pd nanocrystals prepared in Example 1 of the present invention.

[0130] Depend on figure 1 It can be seen that the present invention prepares cubic...

Embodiment 2

[0136] Octahedral Pd{111} / SiO 2 Synthesis of Nanocrystals

[0137] Take 105mg of polyvinylpyrrolidone (Mw=55000), 180mg of citric acid, and 3ml of ethanol and dissolve them in 4ml of ultrapure water in a single-necked flask with a capacity of 25ml, keep the temperature in an oil bath at 80°C for 10min, and then add 1ml of SiO 2 The suspension (150mg / ml) was kept at a constant temperature for 5min, and 3ml of 65mmol / L Na 2 PdCl 4 The aqueous solution reacted for 3h. Finally, centrifuge washing and vacuum drying at room temperature for 24 hours, and then the octahedral Pd{111} / SiO with PVP protective agent on the surface was obtained. 2 Nanocrystalline.

[0138] The octahedral Pd{100} prepared in Example 2 of the present invention was characterized.

[0139] see Figure 4 , Figure 4 TEM image of the octahedral Pd nanocrystals prepared in Example 2 of the present invention.

[0140] Depend on Figure 4 It can be seen that the present invention prepares octahedral Pd nan...