CN108630948B - Preparation method of octahedral palladium-platinum core-shell structure catalyst - Google Patents
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Abstract
The invention discloses a preparation method of an octahedral palladium-platinum core-shell structure catalyst, which comprises the steps of firstly, uniformly dispersing palladium metal particles in an ethylene glycol solution, then adding glycine and chloroplatinic acid into a palladium metal particle-ethylene glycol mixed liquid, and then adding deionized water; and finally, stirring and ultrasonically treating the mixed liquid, transferring the solution into a reaction kettle for hydrothermal reaction, and obtaining the octahedral palladium-platinum core-shell structure catalyst after the reaction is finished. Compared with other octahedral catalysts with the core-shell structures, the octahedral palladium-platinum core-shell structure catalyst synthesized by the invention can be used for synthesizing a palladium core with a specific octahedral morphology without synthesis, so that the complexity of the synthesis process is greatly reduced, the synthesis efficiency and convenience are improved, and meanwhile, the octahedral palladium-platinum core-shell structure catalyst can be used as a high-efficiency electrocatalysis material and directly used in a fuel cell system, so that the problems of shortage of fossil fuel and serious environmental pollution at present are effectively relieved.
Description
Technical Field
The invention relates to the field of catalyst preparation, in particular to a preparation method of a universal octahedral palladium-platinum core-shell structure catalyst.
Background
In recent years, due to the burning of fossil fuels, the global warming and climate change phenomena are becoming more serious, and the earth is faced with the dual problems of resource exhaustion and environmental pollution, so we need to find a new environment-friendly energy source to replace the fossil fuels. The fuel cell is a novel energy source, can directly convert chemical energy existing in fuel and oxidant into power generation device of electric energy, and has the advantages of fuel diversity, environmental affinity and the like[1]. Noble metal nanomaterials are key materials in their catalyst components, directly determining the rate of fuel cell reaction and the morphology of the final product. Among them, the Pt-based catalyst is the acknowledged catalyst with the highest catalytic activity in the low-temperature fuel cell, but the Pt resource has very little reserve on the earth, and the problem of poor stability is often existed in the specific use process, and how to effectively solve the two problemsImproving the catalytic activity of the catalyst is still an international research hotspot.
Among the numerous modifications to platinum-based catalysts, the use of less expensive metals as the inner core and the growth of a very thin platinum shell on the outer surface is one of the most effective methods. Of these, palladium metal and platinum metal have a lattice mismatch of only 0.77% and are therefore among the most common metals used as the core. Whether by liquid-phase reduction[2]Or underpotential deposition[3]In order to synthesize the core-shell catalyst with a specific morphology, the method generally needs to preferentially synthesize a core with a specific morphology and then perform subsequent shell growth. Precise control of the morphology of the seeds adds complexity to the overall synthesis process.
1.S.Lister and G.McLean,PEM fuel cell electrode,Journal of PowerSources,2004,130,61-76.
2.X.Wang,S.I.Choi,L.T.Roling,M.Luo,C.Ma,L.Zhang,M.Chi,J.Liu,Z.Xie,J.A.Herron,M.Mavrikakis,Y.Xia,Palladium–platinum core-shell icosahedra withsubstantially enhanced activity and durability towards oxygen reduction,Nature Communication,2015,6,7594.
3.J.Zhang,Y.Mo,M.B.Vukmirovic,R.Klie,K.Sasaki,R.R.Adzic,PlatinumMonolayer Electrocatalysts for O2Reduction:Pt Monolayer on Pd(111)and onCarbon-Supported Pd Nanoparticles,The Journal of Physical Chemistry B 2004,108,10955-10964.
Disclosure of Invention
The invention aims to overcome the defect that seeds with specific morphology must be used in the existing catalyst for synthesizing the core-shell structure with specific morphology, and provides a method for finally generating the palladium-platinum catalyst with the octahedral core-shell structure by using the seeds with different morphologies. The invention mainly utilizes the reducing agent and the reactant added in the experimental process to achieve the purpose that two processes of kernel structure reconstruction and subsequent shell growth exist simultaneously in the reaction process. No matter what morphology of palladium seeds are added in the reaction process, the octahedral Pd @ Pt core-shell structure catalyst can be obtained in a reaction solution containing glycine and chloroplatinic acid through hydrothermal reduction. The synthesis method can greatly simplify the synthesis process of the palladium-platinum core-shell structure catalyst.
The technical problem to be solved by the invention is realized by the following technical scheme:
a preparation method of an octahedral palladium-platinum core-shell structure catalyst comprises the following steps:
uniformly dispersing palladium metal particles in an ethylene glycol solution;
step two, adding glycine and chloroplatinic acid into the palladium metal particle-ethylene glycol mixed liquid in the step one, and then adding deionized water; the mass ratio of the palladium metal particles to the glycine to the chloroplatinic acid is (0.5-2): (5-30): (1-12), wherein the volume ratio of the ethylene glycol to the deionized water is (0.5-2): (3-5);
step three, stirring and ultrasonically treating the mixed liquid in the step two to uniformly disperse substances in the mixed liquid, and then transferring the solution into a reaction kettle to perform hydrothermal reaction at the reaction temperature of 200-210 ℃ for 0.5-6 hours; the octahedral palladium platinum core-shell structure catalyst is obtained after the reaction is finished.
In the first step, the palladium metal particles are palladium metal catalyst particles or activated carbon supported palladium particles with the shapes of nanocubes, nano chamfered cubes and nano chamfered octahedrons, and the palladium content of the activated carbon supported palladium particles is 10-12%.
In the second step, preferably, the mass ratio of the palladium metal particles to the glycine to the chloroplatinic acid is (0.8-1.6): (7.2-28.8): (1.33-10.53), wherein the volume ratio of the ethylene glycol to the deionized water is (0.5-1.5): (3.5-5).
In the third step, preferably, the stirring time is 5-6 minutes, the ultrasonic time is 5-6 minutes, the reaction temperature of the hydrothermal reaction is 200-205 ℃, and the reaction time is 3-6 hours.
And in the third step, transferring the liquid after the hydrothermal reaction from the hydrothermal kettle to a centrifugal tube, washing with deionized water, wherein the centrifugal speed of the centrifugal tube is 9500-9600 r/min, and centrifuging for 15-20 min.
The invention has the advantages that:
(1) compared with other octahedral catalysts with the core-shell structures, the synthesized octahedral palladium-platinum core-shell structure catalyst can be used for synthesizing a palladium core with a specific octahedral shape without synthesis, so that the complexity of the synthesis process is greatly reduced, and the synthesis efficiency and convenience are improved.
(2) The catalyst with octahedral palladium-platinum core-shell structure can be used as an efficient electrocatalytic material, and can be directly used in a fuel cell system, thereby effectively relieving the problems of shortage of fossil fuel and serious environmental pollution at present.
Drawings
FIG. 1 is a transmission electron micrograph of Pd-1 prepared in example 1;
FIG. 2 is a transmission electron micrograph of Pd-1@ Pt-1 prepared in example 1;
FIG. 3 is a high power transmission electron micrograph of Pd-1@ Pt-1 prepared in example 1;
FIG. 4 is an elemental profile of Pd-1@ Pt-1 prepared in example 1;
FIG. 5 is a transmission electron micrograph of Pd-2 prepared in example 4;
FIG. 6 is a transmission electron micrograph of Pd-2@ Pt-1 prepared in example 4;
FIG. 7 is a transmission electron micrograph of Pd-3 prepared in example 5;
FIG. 8 is a transmission electron micrograph of Pd-3@ Pt-1 prepared in example 5;
FIG. 9 is a transmission electron micrograph of Pd-4 in example 6;
FIG. 10 is a transmission electron micrograph of Pd-4@ Pt-1 in example 6;
FIG. 11 is a graph comparing the methanol oxidation activity of Pd-4 and Pd-4@ Pt-1 obtained in example 6 in a methanol oxidation reaction;
FIG. 12 is a graph comparing the stability of Pd-4 and Pd-4@ Pt-1 obtained in example 6 in a methanol oxidation reaction.
Detailed Description
The present invention is further illustrated by the following specific examples, which are intended to be illustrative, not limiting and are not intended to limit the scope of the invention.
Embodiments 1-6 are methods for synthesizing octahedral palladium-platinum core-shell catalysts using palladium cores of different morphologies according to the present invention
Example 1:
(1) preparation of palladium metal catalyst particles having nanocube structure
a) Accurately weighing 105mg of polyvinylpyrrolidone (PVP for short, molecular weight is 10000), 60mg of ascorbic acid and 600mg of potassium bromide, dissolving in 8mL of deionized water, preheating at 80 ℃ for 10 minutes, and uniformly stirring;
b) 3mL of a solution containing 57mg of sodium tetrachloropalladate was quickly injected into the reaction solution mentioned in the first step, and the reaction was carried out for three hours with a lid closed;
c) transferring the reacted solution into a centrifugal tube, and washing the solution with deionized water for three times, wherein the set rotating speed is 9500r/min and 15min each time;
d) the catalyst obtained above was dispersed in 12mL of ethylene glycol and stored for later use and designated as Pd-1.
(2) Preparation of octahedral palladium-platinum core-shell structure catalyst solution by hydrothermal method
a) Weighing 200mg of glycine and dissolving the glycine into 5mL of water to prepare a glycine solution of 40 mg/mL;
b) dissolving 1g of a chloroplatinic acid hexahydrate medicine into 37.5mL of water to prepare 21.09mg/mL of chloroplatinic acid solution;
c) measuring 1mL of the palladium glycol solution obtained in the first step as a seed, adding the seed into a cleaned 20mL screw glass bottle, measuring 0.72mL of the glycine solution and 0.25mL of the chloroplatinic acid solution, adding the glycine solution and the chloroplatinic acid solution, and finally measuring 3.53mL of water to fix the volume of the solution to 5.5 mL;
(3) octahedral palladium platinum core-shell structure catalyst prepared by hydrothermal method
a) Stirring the obtained 5.5mL solution for five minutes, and then carrying out ultrasonic treatment for five minutes to uniformly mix the solution;
b) transferring the uniformly mixed solution into a 20mL hydrothermal kettle, and placing the hydrothermal kettle into a 200 ℃ oven to keep the temperature for 6 hours;
c) after the reaction is finished, taking the reaction kettle out of the oven, and naturally cooling to room temperature;
d) transferring the solution after the reaction into a centrifuge tube, washing with deionized water for three times, wherein the centrifugation condition is 9500r/min each time and 15min, and the obtained octahedral palladium-platinum core-shell structure catalyst is recorded as Pd-1@ Pt-1.
Example 2:
(1) the procedure for preparing palladium metal catalyst particles having a nanocube structure was the same as in example 1, and Pd-1 was obtained.
(2) Preparation of octahedral palladium-platinum core-shell structure catalyst solution by hydrothermal method
a) Weighing 200mg of glycine and dissolving the glycine into 5mL of water to prepare a glycine solution of 40 mg/mL;
b) dissolving 1g of a chloroplatinic acid hexahydrate medicine into 37.5mL of water to prepare 21.09mg/mL of chloroplatinic acid solution;
c) measuring 1mL of the palladium glycol solution obtained in the first step as a seed, adding the seed into a cleaned 20mL screw glass bottle, measuring 0.72mL of the glycine solution and 0.5mL of the chloroplatinic acid solution, adding the glycine solution and the chloroplatinic acid solution, and finally measuring 3.28mL of water to fix the volume of the solution to 5.5 mL;
(3) the octahedral palladium platinum core-shell structure catalyst prepared by a hydrothermal method is similar to that in example 1, and the obtained octahedral palladium platinum core-shell structure catalyst is recorded as Pd-1@ Pt-2.
Example 3:
(1) the procedure for preparing palladium metal catalyst particles having a nanocube structure was the same as in example 1, and Pd-1 was obtained.
(2) Preparation of octahedral palladium platinum core-shell catalyst solution by hydrothermal method the same as example 1.
(3) Octahedral palladium platinum core-shell structure catalyst prepared by hydrothermal method
a) Stirring the obtained 5.5mL solution for five minutes, and then carrying out ultrasonic treatment for five minutes to uniformly mix the solution;
b) transferring the uniformly mixed solution into a 20mL hydrothermal kettle, and placing the hydrothermal kettle into a 200 ℃ oven to keep the temperature for 0.5 h;
c) after the reaction is finished, taking the reaction kettle out of the oven, and naturally cooling to room temperature;
d) transferring the solution after the reaction into a centrifuge tube, washing with deionized water for three times, wherein the centrifugation condition is 9500r/min each time and 17min, and the obtained octahedral palladium-platinum core-shell structure catalyst is recorded as Pd-1@ Pt-3.
Example 4:
(1) preparation of palladium metal catalyst particles with nano chamfered cubic structure
a) Accurately weighing 105mg of polyvinylpyrrolidone (PVP for short, molecular weight is 10000), 60mg of ascorbic acid and 600mg of potassium bromide, dissolving in 8mL of deionized water, preheating at 80 ℃ for 10 minutes, and uniformly stirring;
b) 3mL of a solution containing 57mg of sodium tetrachloropalladate was quickly injected into the reaction solution mentioned in the first step, and the reaction was carried out for three hours with a lid closed;
c) transferring the reacted solution into a centrifugal tube, and washing the solution with deionized water for three times, wherein the set rotating speed is 9500r/min and 15min each time;
d) the catalyst obtained above was dispersed in 12mL of water and stored for later use.
e) Accurately weighing 105mg of polyvinylpyrrolidone (PVP for short, molecular weight is 10000) and 100uL of HCHO, measuring 0.15mL of aqueous solution of the palladium metal particles, dissolving the aqueous solution in 8mL of deionized water, preheating for 10 minutes at 60 ℃, and uniformly stirring;
f) 29mg of sodium chloropalladate was accurately weighed and dissolved in 3mL of deionized water. Measuring 0.6mL of sodium chloropalladate solution, quickly injecting the solution into the reaction solution mentioned in the first step, covering a cover, and reacting for three hours;
g) transferring the reacted solution into a centrifugal tube, and washing the solution with deionized water for three times, wherein the set rotating speed is 9500r/min and 15min each time;
h) the catalyst obtained above was dispersed in 2mL of ethylene glycol and stored for later use, and the obtained product was recorded as Pd-2.
(2) Preparation of octahedral palladium-platinum core-shell structure catalyst solution by hydrothermal method
a) Weighing 200mg of glycine and dissolving the glycine into 5mL of water to prepare a glycine solution of 40 mg/mL;
b) dissolving 1g of a chloroplatinic acid hexahydrate medicine into 37.5mL of water to prepare 21.09mg/mL of chloroplatinic acid solution;
c) measuring 1mL of the palladium glycol solution obtained in the first step as a seed, adding the seed into a cleaned 20mL screw glass bottle, measuring 0.18mL of the glycine solution and 0.063mL of the chloroplatinic acid solution, adding the glycine solution and the chloroplatinic acid solution, and finally measuring 4.25mL of water to fix the volume of the solution to 5.5 mL;
(3) the octahedral palladium-platinum core-shell structure catalyst prepared by a hydrothermal method is similar to that in example 1, and the obtained octahedral palladium-platinum core-shell structure catalyst is recorded as Pd-2@ Pt-1.
Example 5:
(1) preparation of palladium metal catalyst particles with nano octahedral structure
a) Accurately weighing 105mg of polyvinylpyrrolidone (PVP for short, molecular weight is 10000), 60mg of ascorbic acid and 600mg of potassium bromide, dissolving in 8mL of deionized water, preheating at 80 ℃ for 10 minutes, and uniformly stirring;
b) 3mL of a solution containing 57mg of sodium tetrachloropalladate was quickly injected into the reaction solution mentioned in the first step, and the reaction was carried out for three hours with a lid closed;
c) transferring the reacted solution into a centrifugal tube, and washing the solution with deionized water for three times, wherein the set rotating speed is 9500r/min and 15min each time;
d) the catalyst obtained above was dispersed in 12mL of water and stored for later use.
e) Accurately weighing 105mg of polyvinylpyrrolidone (PVP for short, molecular weight is 10000) and 100uL of HCHO, measuring 0.15mL of aqueous solution of the palladium metal particles, dissolving the aqueous solution in 8mL of deionized water, preheating for 10 minutes at 60 ℃, and uniformly stirring;
f) 29mg of sodium chloropalladate was accurately weighed and dissolved in 3mL of deionized water. Measuring 1.8mL of sodium chloropalladate solution, quickly injecting the solution into the reaction solution mentioned in the first step, covering a cover, and reacting for three hours;
g) transferring the reacted solution into a centrifugal tube, and washing the solution with deionized water for three times, wherein the set rotating speed is 9500r/min and 15min each time;
h) the catalyst obtained above was dispersed in 2mL of ethylene glycol and stored for later use, and the obtained was recorded as Pd-3.
(2) Preparation of octahedral palladium-platinum core-shell structure catalyst solution by hydrothermal method
a) Weighing 200mg of glycine and dissolving the glycine into 5mL of water to prepare a glycine solution of 40 mg/mL;
b) dissolving 1g of a chloroplatinic acid hexahydrate medicine into 37.5mL of water to prepare 21.09mg/mL of chloroplatinic acid solution;
c) measuring 0.8mL of the palladium glycol solution in the step one as a seed, adding the seed into a cleaned 20mL screw-top glass bottle, measuring 0.36mL of the glycine solution and 0.125mL of the chloroplatinic acid solution, adding the glycine solution and the chloroplatinic acid solution, and finally measuring 4.22mL of water to fix the volume of the solution to 5.5 mL;
(3) octahedral palladium platinum core-shell structure catalyst prepared by hydrothermal method
a) Stirring the obtained 5.5mL solution for five minutes, and then carrying out ultrasonic treatment for five minutes to uniformly mix the solution;
b) transferring the uniformly mixed solution into a 20mL hydrothermal kettle, and placing the hydrothermal kettle into a 200 ℃ oven to keep the temperature for 3 hours;
c) after the reaction is finished, taking the reaction kettle out of the oven, and naturally cooling to room temperature;
d) transferring the solution after the reaction into a centrifuge tube, washing with deionized water for three times, wherein the centrifugation condition is 9600r/min each time and 18min, and the obtained octahedral palladium platinum core-shell structure catalyst is recorded as Pd-3@ Pt-1.
Example 6:
(1) treatment of activated carbon-supported palladium particles
Accurately weighing 12mg of activated carbon supported palladium particles (10 mass percent of palladium) and dispersing the particles in 1mL of glycol, carrying out ultrasonic treatment for 10min, uniformly mixing for later use, and marking as Pd-4;
(2) preparation of octahedral palladium-platinum core-shell structure catalyst solution by hydrothermal method
a) Weighing 200mg of glycine and dissolving the glycine into 5mL of water to prepare a glycine solution of 40 mg/mL;
b) dissolving 1g of a chloroplatinic acid hexahydrate medicine into 37.5mL of water to prepare 21.09mg/mL of chloroplatinic acid solution;
c) measuring 1mL of ethylene glycol solution of activated carbon loaded commercial palladium in the first step as seeds, adding the seeds into a cleaned 20mL screw-top glass bottle, measuring 0.72mL of the glycine solution and 0.25mL of the chloroplatinic acid solution, adding the glycine solution and the chloroplatinic acid solution, and finally measuring 3.53mL of water to fix the volume of the solution to 5.5 mL;
(3) the octahedral palladium-platinum core-shell structure catalyst prepared by a hydrothermal method is similar to that in example 1, and the obtained octahedral palladium-platinum core-shell structure catalyst is recorded as Pd-4@ Pt-1.
The palladium cores with different morphologies obtained in the embodiments 1-6 and the octahedral palladium-platinum core-shell structure catalyst obtained by putting the palladium cores with different morphologies are used for size determination. The dimensions of the palladium cores of different morphologies prepared in examples 1 to 6 and the octahedral palladium-platinum core-shell structure catalyst obtained by putting the palladium cores of different morphologies into the palladium cores were measured by using a transmission electron microscope, and the results are shown in the following table:
TABLE 1 Palladium Metal core size and octahedral Palladium platinum core-Shell catalyst size
| Palladium metal core size (nm) | Octahedral palladium platinum core-shell catalyst size (nm) | |
| Pd-1@Pt-1 | 12～16 | 19～23 |
| Pd-1@Pt-2 | 12～16 | 19～23 |
| Pd-1@Pt-3 | 12～16 | 19～23 |
| Pd-2@Pt-1 | 12～16 | 15～19 |
| Pd-3@Pt-1 | 17～23 | 19～25 |
| Pd-4@Pt-1 | 2～4 | 7～9 |
Then, the octahedral palladium-platinum core-shell structure catalyst prepared in example 6 was subjected to measurement of methanol oxidation activity and stability. The octahedral palladium platinum core-shell structure catalyst prepared in example 6 and the activated carbon supported palladium particles were dispersed with ethanol, and the catalyst with a total metal content of 0.002mg was dropped onto a working electrode (glassy carbon electrode) with a diameter of 3mm, and an electrochemical test electrode system was assembled using a platinum sheet electrode of 2 × 2cm as a counter electrode and a saturated silver/silver chloride electrode as a reference electrode, and was placed in a 0.1M HClO system, respectively4Solution and 0.1M HClO4And 2MCH3CV and IV tests were performed on OH in methanol. RHE is measured at a voltage interval of 0.05-1.0V vs. with a scan rate of 50 mV/s. The test for catalyst stability was performed at a voltage of 1.0V vs. rhe.
As shown in figure 1, the size of Pd-1 is 14 +/-2.0 nm, and is used as a core material for subsequent growth; FIG. 2 is a transmission electron micrograph of Pd-1@ Pt-1, the dimensions (long side of the two opposite corners of the octahedron) of which are 21. + -. 2.0nm, the octahedron structure exposing the (111) crystal plane; FIG. 3 shows the result of high-power TEM electron microscopy characterization of Pd-1@ Pt-1, in which a core-shell coating structure is clearly visible, the thickness of a shell layer is about 2nm, and the crystal face can be well matched with the (111) crystal face of Pt by measuring the lattice spacing; FIG. 4 shows the elemental surface scan results for Pd-1@ Pt-1, showing that the Pd-1@ Pt-1 core is composed of Pd and the shell is enriched with Pt, which well demonstrates the formation of octahedral Pd-Pt core-shell catalysts.
FIG. 5 shows the size of Pd-2 is 14.0. + -. 2.0nm, FIG. 6 shows the size of Pd-2@ Pt-1 is 17.0. + -. 2.0 nm; FIG. 7 shows the size of Pd-3 as 20.0. + -. 3.0nm, and the size of Pd-3@ Pt-1 as 22.0. + -. 3.0nm in FIG. 8.
FIG. 9 shows a Pd-4 transmission electron micrograph showing that the Pd-4 particles are amorphous, have disordered crystal planes and have a size of 3 + -1 nm; FIG. 10 shows a transmission electron micrograph of Pd-4@ Pt-1, and the result shows that the size of the activated carbon-supported octahedral palladium platinum core-shell structure catalyst is 8 +/-1 nm.
FIG. 11 is a graph showing the comparison of methanol oxidation activities of Pd-4 and Pd-4@ Pt-1, and FIG. 11 shows that the peak current value of Pd-4@ Pt-1 can reach 1.68mA cm-2About 1.5 times Pd-4; FIG. 12 is a graph comparing the stability of Pd-4 and Pd-4@ Pt-1 in a methanol oxidation reaction, and FIG. 12 is a graph comparing stability tests under test conditions relative to a voltage of 1.0V (vs. RHE) with starting currents of 1.54 and 0.69mA cm for Pd-4@ Pt-1 and Pd-4-2In the first 6 seconds, Pd-4 had been reduced by 50%, whereas Pd-4@ Pt-1 had been reduced by only 7%, i.e., the catalyst remained well active in the initial period of the reaction, and after 200 seconds, Pd-4 had substantially lost activity, whereas Pd-4@ Pt-1 remained at 0.26mA cm even after 1000 seconds of reaction-2Activity of (2).
The octahedral palladium-platinum core-shell catalyst can be prepared by adjusting the process parameters according to the content of the invention, and the octahedral palladium-platinum core-shell catalyst can show good methanol oxidation activity and stability. The technical solution of the present invention has been described above by way of example, and it should be noted that any simple modification, modification or other equivalent replacement by those skilled in the art without inventive work may fall within the scope of protection of the present patent, without departing from the core of the technical solution.
Claims (3)
1. A preparation method of octahedral palladium-platinum core-shell structure catalyst is characterized by comprising the following steps:
uniformly dispersing palladium metal particles in an ethylene glycol solution; the palladium metal particles are palladium metal catalyst particles or activated carbon supported palladium particles with a nanocube shape, and the palladium content of the activated carbon supported palladium particles is 10-12%;
step two, adding glycine and chloroplatinic acid into the palladium metal particle-ethylene glycol mixed liquid in the step one, and then adding deionized water; the mass ratio of the palladium metal particles to the glycine to the chloroplatinic acid is (0.5-2): (5-30): (1-12), wherein the volume ratio of the ethylene glycol to the deionized water is (0.5-2): (3-5);
step three, stirring and ultrasonically treating the mixed liquid obtained in the step two to uniformly disperse substances in the mixed liquid, then transferring the solution into a reaction kettle for hydrothermal reaction at the reaction temperature of 200-210 ℃ for 0.5-6 hours, transferring the liquid after the hydrothermal reaction into a centrifugal tube from the hydrothermal kettle, washing the liquid with deionized water, and centrifuging the liquid for 15-20 minutes at the centrifugal speed of 9500-9600 r/min; after the reaction is finished, the octahedral palladium-platinum core-shell structure catalyst is obtained, and the minimum octahedral palladium-platinum core-shell structure catalyst size is 7-9 nm.
2. The preparation method of the octahedral palladium platinum core-shell structure catalyst according to claim 1, characterized in that: in the second step, the mass ratio of the palladium metal particles to the glycine to the chloroplatinic acid is (0.8-1.6): (7.2-28.8): (1.33-10.53), wherein the volume ratio of the ethylene glycol to the deionized water is (0.5-1.5): (3.5-5).
3. The preparation method of the octahedral palladium platinum core-shell structure catalyst according to claim 1, characterized in that: in the third step, the stirring time is 5-6 minutes, the ultrasonic time is 5-6 minutes, the reaction temperature of the hydrothermal reaction is 200-205 ℃, and the reaction time is 3-6 hours.
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| CN113036168B (en) * | 2021-03-04 | 2022-07-05 | 合肥工业大学 | Cubic PtPd @ Pt core-shell nano cage electrocatalyst and preparation method and application thereof |
| CN113948729A (en) * | 2021-10-20 | 2022-01-18 | 江苏大学 | Preparation method of binary metal platinum-palladium prismatic catalyst and application of catalyst in direct methanol fuel cell |
| CN116344839B (en) * | 2023-01-13 | 2024-05-28 | 一汽解放汽车有限公司 | High-potential catalyst and preparation method and application thereof |
| CN117174922B (en) * | 2023-11-02 | 2024-02-13 | 武汉理工大学 | Pd@Pt broad-edge core-shell nano regular tetrahedron catalyst, and preparation method and application thereof |
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| CN104525189A (en) * | 2014-12-29 | 2015-04-22 | 东南大学 | Polyhedral Pd-Pt alloy nano catalyst and preparation method and application of nano catalyst |
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