A platinum-cerium-based catalyst, a preparation method and application thereof

Abstract

The application provides a platinum-cerium-based catalyst and a preparation method and application thereof, the platinum-cerium-based catalyst comprising a cerium-based carrier and a platinum-based redox component distributed on the surface of the cerium-based carrier; the platinum-based redox component comprises platinum nanoclusters; and the cerium-based carrier comprises a surface vacancy regulator. By introducing the surface vacancy regulator into the platinum-cerium-based catalyst, the alkalinity, oxygen vacancy concentration and cerium vacancy concentration of the surface of the cerium-based carrier are changed, the stable existence of the platinum nanoclusters under high-temperature oxidation treatment conditions is realized, and the stability and catalytic activity of the platinum-cerium-based catalyst are significantly improved.

Description

Technical Field

[0001] This invention relates to the field of environmental protection and air pollution control technology, specifically to the catalytic oxidation of gaseous pollutants, and more particularly to a platinum-cerium-based catalyst, its preparation method, and its application. Background Technology

[0002] Cerium-based oxides, due to their strong oxygen storage and release capabilities, can catalyze most reactions, including CO oxidation, water-gas conversion, and alkane dehydrogenation, when combined with redox components (such as Pt, Pd, and Ir). In particular, Pt / CeO2 can effectively eliminate pollutants such as CO and NO in automobile exhaust and is an important component of three-way catalysts. To cope with complex operating conditions and stringent emission standards, it is necessary to improve the stability testing of catalysts under both low and high temperature conditions to meet the exhaust gas treatment requirements during normal vehicle operation.

[0003] Pt / CeO2 is a material system with strong metal-support interactions. Under oxygen-rich, high-temperature conditions, Pt clusters with high CO oxidation activity gradually form completely dispersed Pt single atoms on the CeO2 surface. At this point, due to the strong bonding between the overly stable Pt single atoms and the support, the ability to form bonds with the gaseous CO species and the ability to activate CO are significantly reduced, resulting in a significant decrease in the catalyst's catalytic activity for CO.

[0004] CN115770570A discloses a cerium oxide-supported atomically dispersed Pt catalyst and its redispersion preparation method, comprising: firstly, preparing a CeO2-supported Pt nanoparticle catalyst, then calcining it at high temperature in an oxidizing atmosphere, causing the Pt nanoparticles to redisperm on the CeO2(100) crystal surface; and adjusting the Pt loading to control the Pt dispersion to achieve atomic-level dispersion, thus obtaining the CeO2-supported atomically dispersed Pt catalyst. By controlling the Pt loading, not only can the particle size be controlled from single atoms and multi-atom particles to clusters, but also the distance between single atoms on the CeO2 surface can be controlled.

[0005] CN101670286A discloses a method for preparing a class of supported transition metal or alloy nanoclusters catalysts by supporting solvent- and simple ion-stable transition metal or alloy nanoclusters synthesized via an "alkali-polyol method" on a carbon or oxide support. The catalyst contains 0.1 wt%-50 wt% of transition metal or alloy nanoclusters with a particle size of 0.7 nm-5 nm. The transition metal or alloy nanoclusters in the catalyst are distributed on the outer surface of the support material or within mesopores and macropores, exhibiting high surface atomic availability.

[0006] CN114832817A discloses a sheet-like atomic-scale Pt / CeO2 catalyst with ultra-high Pt loading. The catalyst exhibits an extremely high loading of active metal Pt, maintaining an atomic-scale dispersion even at 10%, and demonstrates significantly superior catalytic water-gas shift reaction performance. This is in contrast to commercially available Pt / CeO2 catalysts and microspherical atomic-scale Pt / CeO2 catalysts. However, this technology requires ultra-high Pt loading to overcome the limitations of Pt / CeO2 applications, significantly increasing costs.

[0007] Therefore, there is an urgent need to design a highly stable cerium-based oxide-supported platinum catalyst to ensure that platinum nanoclusters can remain stable at high temperatures during normal vehicle operation, thereby enabling long-term and effective treatment of polluting gases in exhaust gases. Summary of the Invention

[0008] To address the shortcomings of existing technologies, the present invention aims to provide a platinum-cerium-based catalyst, its preparation method, and its applications. This invention introduces a surface vacancy regulator into the platinum-cerium-based catalyst, altering the alkalinity, oxygen vacancy concentration, and cerium vacancy concentration on the cerium-based support surface. This weakens the strong interaction between the platinum-based redox components and the cerium-based support, achieving stable platinum nanoclusters under high-temperature oxidation conditions. This significantly improves the stability and catalytic activity of the platinum-cerium-based catalyst, exhibiting relatively excellent catalytic performance even under oxygen-rich high-temperature environments, as well as strong resistance to environmental interference.

[0009] To achieve this objective, the present invention adopts the following technical solution:

[0010] In a first aspect, the present invention provides a platinum-cerium-based catalyst, the platinum-cerium-based catalyst comprising a cerium-based support and a platinum-based redox component distributed on the surface of the cerium-based support;

[0011] The platinum-based redox component includes platinum nanoclusters;

[0012] The cerium-based support includes cerium dioxide and a surface vacancy regulator.

[0013] This invention introduces a surface vacancy regulator into a platinum-cerium-based catalyst to change the alkalinity, oxygen vacancy concentration, and cerium vacancy concentration on the surface of the cerium-based support, thereby weakening the strong interaction between the platinum-based redox components and the cerium-based support. This enables the stable existence of platinum nanoclusters under high-temperature oxidation conditions and significantly improves the stability and catalytic activity of the platinum-cerium-based catalyst.

[0014] In this invention, the surface vacancy regulator is a metallic element with a large ionic radius or high electronegativity, which can adjust the pH of the support surface, thereby reducing the Lewis base content and strength on the support surface. This results in a decrease in the low-coordination O content and cerium vacancy content on the support surface, significantly reducing the proportion of Pt-O-Ce single-atom bonds formed by platinum occupying cerium vacancies. This achieves the goal of controlling the number of single-atom dispersion sites and increasing the proportion of platinum nanoclusters. Simultaneously, under the action of the surface vacancy regulator, a high concentration of oxygen vacancies can be formed inside and on the surface of the cerium-based support, thus maintaining electroneutrality and reducing internal stress.

[0015] In this invention, the platinum-based redox component exists in a zero-valent or partially oxidized state.

[0016] Preferably, the surface vacancy modifier comprises an ionic radius... And / or elements with electronegativity ≥ 1.7.

[0017] Preferably, the surface vacancy modifier includes any one or a combination of at least two of neodymium (Nd), bismuth (Bi), tungsten (W), or molybdenum (Mo).

[0018] In this invention, the molar percentage of the surface vacancy regulator affects the alkalinity, oxygen vacancy concentration, and cerium vacancy concentration on the surface of the cerium-based support, thereby affecting the strength of the interaction between the platinum-based redox components and the cerium-based support, and achieving the stable existence of platinum nanoclusters under high-temperature oxidation treatment conditions. If the molar percentage of the surface vacancy regulator is too high, it will introduce an excessively high concentration of oxygen vacancies, inhibiting the oxygen storage and release capacity of the cerium-based support, and may even cause phase separation. If the molar percentage of the surface vacancy regulator is too low, it cannot effectively inhibit the redispersion of platinum nanoclusters.

[0019] Preferably, the molar percentage of the surface vacancy regulator in the cerium-based support is 8%-30%, for example, it can be 8%, 10%, 12%, 14%, 16%, 18%, 20%, 21%, 23%, 25%, 27%, 29% or 30%, including but not limited to the listed values. Other unlisted values ​​within the range are also applicable, preferably 10%-20%.

[0020] In this invention, the average size of platinum nanoclusters affects the catalytic activity of the reaction. If the average size of the platinum-cerium-based catalyst is too small, it is easy to form single-atom platinum, which limits the adsorption and activation of CO. If the average size is too large, the atom utilization efficiency is low, resulting in the platinum not being fully utilized inside the particles.

[0021] Preferably, the average size of the platinum nanoclusters is 1nm-5nm, for example, it can be 1nm, 1.5nm, 2nm, 2.5nm, 3nm, 4nm or 5nm, including but not limited to the listed values. Other unlisted values ​​within the range are also applicable, preferably 1nm-3nm.

[0022] In this invention, the mass percentage of the platinum-based reducing component in the platinum-cerium-based catalyst also affects the reaction activity. If the mass percentage of the platinum-based reducing component is too large, although there is no difficulty in redispersing the platinum nanoclusters, the catalytic activity of the system will have an upper limit, and the excess platinum atoms cannot be effectively utilized. If the mass percentage of the platinum-based reducing component is too small, platinum single atoms with low activity will be formed.

[0023] Preferably, in the platinum-cerium-based catalyst, the mass percentage of the platinum-based reducing component is 0.1%-5%, for example, it can be 0.1%, 0.3%, 0.5%, 0.7%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, or 5%, including but not limited to the listed values. Other unlisted values ​​within the range are also applicable, preferably 0.5%-1%.

[0024] Preferably, the platinum-based redox component further includes a second metal.

[0025] In this invention, a second metal is introduced into the platinum-based redox component to form a synergistic effect, which is beneficial to promoting the reaction.

[0026] Preferably, the second metal comprises any one or a combination of at least two of Pd, Ru, or Ir, with typical but non-limiting combinations including Pd and Ru, Pd and Ir, or Ru and Ir.

[0027] Preferably, the mass percentage of the second metal is ≤30%, for example, it can be 0, 5%, 10%, 15%, 20%, 25% or 30%, including but not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0028] Preferably, the cerium-based support further includes a metal oxide.

[0029] In this invention, the introduction of metal oxides into the cerium-based support is beneficial to improving the high-temperature stability of the support and preventing a serious decrease in the specific surface area of ​​cerium oxide due to excessively high operating temperatures.

[0030] Preferably, the mass percentage of metal oxide in the cerium-based support is ≤20%, for example, it can be 0%, 5%, 10%, 15% or 20%, including but not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0031] Preferably, the metal oxide includes any one or a combination of at least two of aluminum oxide, manganese dioxide, titanium dioxide, cobalt oxide, nickel oxide, or copper oxide. Typical but non-limiting combinations include manganese dioxide and titanium dioxide, cobalt oxide and nickel oxide, titanium dioxide and cobalt oxide, or copper oxide and manganese dioxide.

[0032] In a second aspect, the present invention provides a method for preparing a platinum-cerium-based catalyst as described in the first aspect, the method comprising:

[0033] A solution of cerium-based support and platinum-based nanoparticles is mixed and dried to obtain a platinum-cerium-based catalyst precursor. The platinum-cerium-based catalyst precursor is then calcined to obtain the platinum-cerium-based catalyst.

[0034] In this invention, the drying method for the platinum-cerium-based catalyst precursor obtained after mixing the cerium-based support with the platinum-based nanoparticle solution is not specifically limited, with the aim of achieving complete solvent evaporation.

[0035] Preferably, the drying temperature for obtaining the platinum-cerium-based catalyst precursor is 50°C-80°C, for example, 50°C, 55°C, 60°C, 65°C, 70°C, 75°C or 80°C, including but not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0036] Preferably, the method for preparing the cerium-based support includes:

[0037] A mixed solution is obtained by mixing a cerium source, a surface vacancy regulator precursor, and a solvent. The solution is then reacted to obtain a cerium-based support precursor. The cerium-based support precursor is then calcined to obtain the cerium-based support.

[0038] Preferably, in the mixed solution, the concentrations of the cerium source and the surface vacancy regulator precursor are each independently 0.1 mmol / mL to 0.5 mmol / mL, for example, 0.1 mmol / mL, 0.2 mmol / mL, 0.3 mmol / mL, 0.4 mmol / mL or 0.5 mmol / mL, including but not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0039] Preferably, the molar ratio of cerium source to surface vacancy regulator precursor in the mixed solution is (70-92):(8-30), for example, it can be 70:30, 72:28, 74:26, 76:24, 78:22, 80:20, 82:18, 84:16, 86:14, 88:12, 90:10 or 92:8, including but not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0040] Preferably, the cerium source includes any one or a combination of two of cerium nitrate and cerium chloride.

[0041] Preferably, the surface vacancy regulator precursor comprises any one or a combination of at least two of neodymium salts, bismuth salts, tungstates, or molybdates.

[0042] Preferably, the surface vacancy regulator precursor includes any one or a combination of at least two of neodymium nitrate, bismuth nitrate, ammonium metatungstate, and ammonium molybdate.

[0043] Preferably, the solvent includes water and / or ethanol.

[0044] Preferably, the method for obtaining the cerium-based support precursor by the reaction includes any one of chemical coprecipitation, hydrothermal method or sol-gel method.

[0045] Preferably, the method for preparing the cerium-based support further includes aging and drying the prepared cerium-based support precursor.

[0046] Preferably, the aging temperature is 20℃-40℃, for example, it can be 20℃, 22℃, 24℃, 26℃, 28℃, 30℃, 32℃, 34℃, 36℃, 38℃ or 40℃, including but not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0047] Preferably, the aging time is 4h-12h, for example, it can be 4h, 5h, 6h, 7h, 8h, 9h, 10h, 11h or 12h, including but not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0048] Preferably, the drying temperature is 60℃-100℃, for example, it can be 60℃, 65℃, 70℃, 75℃, 80℃, 85℃, 90℃, 95℃ or 100℃, including but not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0049] Preferably, the calcination temperature of the cerium-based support precursor is 500℃-600℃, for example, it can be 500℃, 510℃, 520℃, 530℃, 540℃, 550℃, 560℃, 570℃, 580℃, 590℃ or 600℃, including but not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0050] Preferably, the calcination time of the cerium-based support precursor is 3h-6h, for example, it can be 3h, 3.5h, 4h, 4.5h, 5h, 5.5h or 6h, including but not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0051] Preferably, the heating rate of calcining the cerium-based support precursor is 2℃ / min-10℃ / min, for example, it can be 2℃ / min, 3℃ / min, 4℃ / min, 5℃ / min, 6℃ / min, 7℃ / min, 8℃ / min, 9℃ / min or 10℃ / min, including but not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0052] In this invention, the concentration of platinum-based nanoparticles in the platinum-based nanoparticle solution affects the initial dispersion of platinum nanoclusters on the carrier surface. If the concentration is too high, it will not be conducive to the uniform dispersion of platinum on the carrier surface and may lead to agglomeration, which may result in misjudgment of the dispersibility of platinum nanoclusters.

[0053] Preferably, the concentration of platinum-based nanoparticles in the platinum-based nanoparticle solution is 1 mg / mL to 3 mg / mL, for example, it can be 1 mg / mL, 1.2 mg / mL, 1.4 mg / mL, 1.6 mg / mL, 1.8 mg / mL, 2 mg / mL, 2.2 mg / mL, 2.4 mg / mL, 2.6 mg / mL, 2.8 mg / mL or 3 mg / mL, including but not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0054] Preferably, the platinum-based nanoparticles are prepared by reducing a platinum-based precursor.

[0055] Preferably, the platinum-based precursor comprises a platinum salt and a second metal salt.

[0056] Preferably, the platinum salt comprises any one or a combination of at least two of platinum nitrate, platinum acetylacetonate, platinum chloride, or platinum acetate. Typical but non-limiting combinations include platinum nitrate and platinum acetylacetonate, platinum chloride and platinum acetate, platinum acetylacetonate and platinum chloride, or platinum acetate and platinum nitrate.

[0057] Preferably, the second metal salt includes any one or a combination of at least two of Pd, Ru, or Ir salts, with typical but not limited combinations including Pd and Ru, Pd and Ir, or Ru and Ir.

[0058] Preferably, the Pd salt comprises palladium nitrate and / or palladium chloride.

[0059] Preferably, the Ru salt comprises ruthenium chloride and / or ruthenium acetate.

[0060] Preferably, the Ir salt comprises any one or a combination of at least two of iridium trichloride, ammonium iridate, or iridium tetrachloride. Typical but non-limiting combinations include iridium trichloride and ammonium iridate, iridium tetrachloride and iridium trichloride, or ammonium iridate and iridium tetrachloride.

[0061] Preferably, the method of reducing the platinum-based precursor includes any one of ethylene glycol reduction, ethanol reduction, or sodium borohydride reduction.

[0062] Preferably, the temperature for reducing the platinum-based precursor is 120℃-160℃, for example, it can be 120℃, 130℃, 140℃, 150℃ or 160℃, including but not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0063] Preferably, the reduction time of the platinum-based precursor is 3h-8h, for example, it can be 3h, 4h, 5h, 6h, 7h or 8h, including but not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0064] In this invention, after the reaction of reducing the platinum-based precursor is completed, the platinum-based nanoparticles are further washed by centrifugation with acetone, dispersed with ethanol, and the concentration is determined by ICP to prepare a platinum-based nanoparticle solution.

[0065] Preferably, the method of mixing the cerium-based support with the platinum-based nanoparticle solution includes stirring.

[0066] Preferably, the stirring rate is 300 r / min to 800 r / min, for example, it can be 300 r / min, 400 r / min, 500 r / min, 600 r / min, 700 r / min or 800 r / min, including but not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0067] Preferably, the stirring time is 2h-4h, for example, it can be 2h, 2.5h, 3h, 3.5h or 4h, including but not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0068] Preferably, the drying temperature for obtaining the platinum-cerium-based catalyst precursor is 50°C-80°C, for example, 50°C, 55°C, 60°C, 65°C, 70°C, 75°C or 80°C, including but not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0069] In this invention, the calcination temperature of the platinum-cerium-based catalyst precursor affects the dispersion state of platinum. If the temperature is too high, the stability of the surface vacancy regulator will deteriorate, resulting in an unsatisfactory effect in inhibiting the redispersion of platinum nanoclusters. For example, Bi element will have a certain degree of volatility after exceeding 700°C.

[0070] Preferably, the calcination temperature of the platinum-cerium-based catalyst precursor is 400℃-600℃, for example, it can be 400℃, 450℃, 500℃, 550℃ or 600℃, including but not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0071] Preferably, the calcination time of the platinum-cerium-based catalyst precursor is 4h-12h, for example, it can be 4h, 5h, 6h, 7h, 8h, 9h, 10h, 11h or 12h, including but not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0072] Preferably, the heating rate of calcining the platinum-cerium-based catalyst precursor is 2℃ / min-5℃ / min, for example, it can be 2℃ / min, 2.5℃ / min, 3℃ / min, 3.5℃ / min, 4℃ / min, 4.5℃ / min or 5℃ / min, including but not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0073] Thirdly, the present invention provides an application of the platinum-cerium-based catalyst as described in the first aspect, wherein the platinum-cerium-based catalyst is used for the catalytic oxidative removal of gaseous pollutants.

[0074] Compared with the prior art, the present invention has the following beneficial effects:

[0075] (1) This invention introduces a surface vacancy regulator into the platinum-cerium-based catalyst to change the alkalinity, oxygen vacancy concentration and cerium vacancy concentration on the surface of the cerium-based support, thereby weakening the strong interaction between the platinum-based redox components and the cerium-based support, realizing the stable existence of platinum nanoclusters under high-temperature oxidation treatment conditions, significantly improving the stability and catalytic activity of the platinum-cerium-based catalyst, and exhibiting relatively excellent catalytic performance even in oxygen-rich high-temperature environments, as well as strong resistance to environmental interference.

[0076] (2) The platinum-cerium-based catalyst provided by the present invention has a simple preparation method, low cost and wide range of applications. It not only broadens the range of platinum-cerium-based catalysts used under high temperature oxidation conditions, but also provides an efficient, economical and widely applicable catalyst preparation route in practical applications.

[0077] (3) The platinum-cerium-based catalyst provided by the present invention has a complete CO conversion temperature of less than 180°C under the condition of 30000 mL / (h·g), and can even be less than 140°C; and after the catalyst is treated with air at 500°C for 4 hours, the reaction temperature rise corresponding to a CO conversion rate of 50% is less than 15°C. Attached Figure Description

[0078] Figure 1The activity curve of the platinum-cerium-based catalyst prepared for this invention under the condition of 30000 mL / (h·g).

[0079] Figure 2 The activity curve of the platinum-cerium-based catalyst prepared for this invention under the condition of 150,000 mL / (h·g).

[0080] Figure 3 The in-situ infrared curve of carbon monoxide for the platinum-cerium-based catalyst prepared in Example 1 of this invention.

[0081] Figure 4 The in-situ infrared curve of carbon monoxide for the platinum-cerium-based catalyst prepared in Example 2 of this invention.

[0082] Figure 5 The image shows the in-situ infrared curve of carbon monoxide in the platinum-cerium-based catalyst prepared in Comparative Example 1 of this invention.

[0083] Figure 6 The image shows the in-situ infrared curve of carbon monoxide in the platinum-cerium-based catalyst prepared in Comparative Example 2 of this invention.

[0084] Figure 7 The above are XPS Pt spectra of the platinum-cerium-based catalysts prepared in Example 1 and Comparative Example 1 of this invention.

[0085] Figure 8 The above are XPS O spectra of the platinum-cerium based catalysts prepared in Example 1 and Comparative Example 1 of this invention.

[0086] Figure 9 The above are XPS Pt spectra of the platinum-cerium based catalysts prepared in Example 2 and Comparative Example 2 of this invention.

[0087] Figure 10 The above are XPS O spectra of the platinum-cerium based catalysts prepared in Example 2 and Comparative Example 2 of this invention.

[0088] Figure 11 The CO2 desorption program curves are shown for the cerium-based catalysts prepared in Example 1 and Comparative Example 1 of this invention.

[0089] Figure 12 This is a spherical aberration electron microscope image of the platinum-cerium-based catalyst prepared in Example 2 of the present invention.

[0090] Figure 13 This is a spherical aberration electron microscope image of the platinum-cerium-based catalyst prepared in Comparative Example 2 of this invention. Detailed Implementation

[0091] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention in any way.

[0092] Example 1

[0093] This embodiment provides a platinum-cerium-based catalyst, wherein the loading of the platinum-based redox component is 1 wt%, and the molar percentage of the bismuth surface vacancy regulator in the cerium-based support is 10%.

[0094] The preparation method of the platinum-cerium-based catalyst includes:

[0095] (1) Preparation of cerium-based support by coprecipitation method: 2.3158 g of cerium nitrate hexahydrate and 0.2856 g of bismuth nitrate pentahydrate were weighed and completely dissolved in 30 mL of 2 mol / L HNO3. Ammonia was added dropwise under stirring to adjust the pH of the solution to 9.5. Stirring was continued for 1 h, and the solution was aged at 30 °C for 8 h. The sample was then washed twice by centrifugation with water and ethanol (4000 rpm, 5 min each). The sample was dried at 60 °C to obtain the cerium-based support precursor. The cerium-based support precursor was calcined in a muffle furnace at a heating rate of 5 °C / min, a calcination temperature of 500 °C, and a calcination time of 4 h to obtain the cerium-based support.

[0096] (2) Preparation of platinum nanoparticle solution: 465 mg of Pt(NO3)2 (16.76 wt%) was dissolved in 9 mL of ethylene glycol, and 315 mg of PVP(k30) was dissolved in 24 mL of ethylene glycol. The two solutions were mixed in a 100 mL three-necked flask. The reaction gas was first purged with N2, then heated to 120 °C and reacted for 5 h. The mixture was then washed by centrifugation with 9 times its volume of acetone, and finally dispersed with ethanol to obtain the platinum nanoparticle solution. The concentration of the nanoparticle solution was determined by ICP and controlled at 2.5 mg / mL.

[0097] (3) Preparation of platinum-cerium-based catalyst: Take 4 mL of platinum nanoparticle solution from step (2) and add it to 990 mg of the support obtained in step (1). Stir at room temperature for 3 h on an electromagnetic stirrer with a magnetic stirrer speed of 300 r / min. Then stir and dry at 60 °C. Finally, calcine at 400 °C for 4 h in a muffle furnace with a calcination heating rate of 5 °C / min to obtain the platinum-cerium-based catalyst.

[0098] Example 2

[0099] This embodiment provides a platinum-cerium-based catalyst, wherein the loading of the platinum-based redox component is 1 wt%, and the molar percentage of the bismuth surface vacancy regulator in the cerium-based support is 10%.

[0100] The preparation method of the platinum-cerium-based catalyst includes:

[0101] (1) Preparation of cerium-based support by coprecipitation method: 2.3158 g of cerium nitrate hexahydrate and 0.2856 g of bismuth nitrate pentahydrate were weighed and completely dissolved in 30 mL of 2 mol / L HNO3. Ammonia was added dropwise under stirring to adjust the pH of the solution to 9.5. Stirring was continued for 1 h, and the solution was aged at 30 °C for 8 h. The sample was then washed twice by centrifugation with water and ethanol (4000 rpm, 5 min each). The sample was dried at 60 °C to obtain the cerium-based support precursor. The cerium-based support precursor was calcined in a muffle furnace at a heating rate of 5 °C / min, a calcination temperature of 500 °C, and a calcination time of 4 h to obtain the cerium-based support.

[0102] (2) Preparation of platinum nanoparticle solution: 465 mg of Pt(NO3)2 (16.76 wt%) was dissolved in 9 mL of ethylene glycol, and 315 mg of PVP(k30) was dissolved in 24 mL of ethylene glycol. The two solutions were mixed in a 100 mL three-necked flask. The reaction gas was first purged with N2, then heated to 120 °C and reacted for 5 h. The mixture was then washed by centrifugation with 9 times its volume of acetone, and finally dispersed with ethanol to obtain the platinum nanoparticle solution. The concentration of the nanoparticle solution was determined by ICP and controlled at 2.5 mg / mL.

[0103] (3) Preparation of platinum-cerium-based catalyst: Take 4 mL of the platinum nanoparticle solution from step (2) and add it to 990 mg of the support obtained in step (1). Stir at room temperature for 3 h on an electromagnetic stirrer with a magnetic stirrer speed of 300 r / min. Then stir and dry at 60 °C. Finally, calcine at 500 °C for 4 h in a muffle furnace with a calcination heating rate of 5 °C / min to obtain the platinum-cerium-based catalyst.

[0104] Example 3

[0105] This embodiment provides a platinum-cerium-based catalyst, wherein the loading of the platinum-based redox component is 1 wt%, and the molar percentage of the bismuth surface vacancy regulator in the cerium-based support is 15%.

[0106] The preparation method of the platinum-cerium-based catalyst is the same as that of Example 1, except that the mass of Ce precursor is changed to 2.1871g and the mass of Bi precursor is changed to 0.4312g in step (1) of Example 1.

[0107] Example 4

[0108] This embodiment provides a platinum-cerium-based catalyst, wherein the loading of the platinum-based redox component is 1 wt%, and the molar percentage of the bismuth surface vacancy regulator in the cerium-based support is 15%.

[0109] The preparation method of the platinum-cerium-based catalyst is the same as that of Example 2, except that the mass of Ce precursor is changed to 2.1871g and the mass of Bi precursor is changed to 0.4312g in step (1) of Example 1.

[0110] Example 5

[0111] This embodiment provides a platinum-cerium-based catalyst, wherein the loading of the platinum-based redox component is 1 wt%, and the molar percentage of the bismuth surface vacancy regulator in the cerium-based support is 20%.

[0112] The preparation method of the platinum-cerium-based catalyst is the same as that in Example 1, except that the mass of Ce precursor is changed to 2.0585g and the mass of Bi precursor is changed to 0.5749g in step (1) of Example 1.

[0113] Example 6

[0114] This embodiment provides a platinum-cerium-based catalyst, wherein the loading of the platinum-based redox component is 1 wt%, and the molar percentage of the bismuth surface vacancy regulator in the cerium-based support is 20%.

[0115] The preparation method of the platinum-cerium-based catalyst is the same as that of Example 2, except that the mass of Ce precursor is changed to 2.0585g and the mass of Bi precursor is changed to 0.5749g in step (1) of Example 1.

[0116] Example 7

[0117] This embodiment provides a platinum-cerium-based catalyst, wherein the loading of the platinum-based redox component is 4.5 wt%, and the molar percentage of the neodymium surface vacancy regulator in the cerium-based support is 10%.

[0118] The preparation method of the platinum-cerium-based catalyst includes:

[0119] (1) Preparation of cerium-based support by coprecipitation method: 1.8012 g of cerium nitrate hexahydrate and 0.2598 g of neodymium nitrate hexahydrate were weighed and completely dissolved in 30 mL of H2O. Ammonia was added dropwise under stirring to adjust the pH of the solution to 9. Stirring was continued for 1 h, and the mixture was aged at 20 °C for 12 h. The sample was then washed twice by centrifugation with water and ethanol (4000 rpm, 5 min each). The sample was dried at 100 °C to obtain the cerium-based support precursor. The cerium-based support precursor was calcined in a muffle furnace at a heating rate of 2 °C / min, a calcination temperature of 600 °C, and a calcination time of 3 h to obtain the cerium-based support.

[0120] (2) Preparation of platinum nanoparticle solution: 465 mg of Pt(NO3)2 (16.76 wt%) was dissolved in 9 mL of ethylene glycol, and 315 mg of PVP(k30) was dissolved in 24 mL of ethylene glycol. The two solutions were mixed and placed in a 100 mL three-necked flask. The reaction gas was first purged with N2, and then heated to 120 °C for 5 h. After that, the mixture was washed by centrifugation with 9 times its volume of acetone, and finally dispersed with ethanol to obtain the platinum nanoparticle solution. The concentration of the nanoparticle solution was determined by ICP and controlled at 3 mg / mL.

[0121] (3) Preparation of platinum-cerium-based catalyst: 15 mL of platinum nanoparticle solution from step (2) was added to 955 mg of the support obtained in step (1). The mixture was stirred at room temperature for 2 h on an electromagnetic stirrer with a magnetic stirring speed of 800 r / min. Then, it was dried by stirring at 80 °C and finally calcined in a muffle furnace at 500 °C for 12 h with a calcination heating rate of 2 °C / min. The platinum-cerium-based catalyst was finally obtained.

[0122] Example 8

[0123] This embodiment provides a platinum-cerium-based catalyst, wherein the loading of the platinum-based redox component is 0.5 wt%, and the molar percentage of the tungsten surface vacancy regulator in the cerium-based support is 20%.

[0124] The preparation method of the platinum-cerium-based catalyst includes:

[0125] (1) Preparation of cerium-based support by coprecipitation method: 2.3673 g of cerium nitrate hexahydrate and 0.29 g of ammonium metatungstate were weighed and completely dissolved in 30 mL of H2O. Ammonia was added dropwise under stirring to adjust the pH of the solution to 11. Stirring was continued for 1 h, and the mixture was aged at 40 °C for 4 h. The sample was then washed twice by centrifugation with water and ethanol (4000 rpm, 5 min each). The sample was dried at 80 °C to obtain the cerium-based support precursor. The cerium-based support precursor was calcined in a muffle furnace at a heating rate of 10 °C / min, a calcination temperature of 550 °C, and a calcination time of 6 h to obtain the cerium-based support.

[0126] (2) Preparation of platinum nanoparticle solution: 465 mg of Pt(NO3)2 (16.76 wt%) was dissolved in 9 mL of ethylene glycol, and 315 mg of PVP(k30) was dissolved in 24 mL of ethylene glycol. The two solutions were mixed and placed in a 100 mL three-necked flask. The reaction gas was first purged with N2, then heated to 120 °C and reacted for 5 h. Afterward, the mixture was washed by centrifugation with 9 times its volume of acetone, and finally dispersed with ethanol to obtain the platinum nanoparticle solution. The concentration of the nanoparticle solution was determined by ICP and controlled at 1 mg / mL.

[0127] (3) Preparation of platinum-cerium-based catalyst: Take 5 mL of platinum nanoparticle solution from step (2) and add it to 995 mg of the support obtained in step (1). Stir at room temperature for 4 h on an electromagnetic stirrer with a magnetic stirring speed of 500 r / min. Then stir and dry at 50 °C. Finally, calcine at 600 °C for 8 h in a muffle furnace with a calcination heating rate of 3 °C / min to obtain the platinum-cerium-based catalyst.

[0128] Example 9

[0129] This embodiment provides a platinum-cerium-based catalyst, wherein the loading of the platinum-based redox component is 2 wt%, and the molar percentage of the molar vacancy regulator on the molar support is 10%.

[0130] The preparation method of the platinum-cerium-based catalyst includes:

[0131] (1) Preparation of cerium-based support by coprecipitation method: First, 0.1039 g of ammonium molybdate and 2 g of citric acid were completely dissolved in 30 mL of H2O. Then, 2.3158 g of cerium nitrate hexahydrate was added, and ammonia was added dropwise to adjust the pH of the solution to 10 while stirring. Stirring was continued for 1 h, and the solution was aged at 40 °C for 4 h. Then, the sample was washed twice by centrifugation with water and ethanol (4000 rpm, 5 min), and dried at 80 °C to obtain the cerium-based support precursor. The cerium-based support precursor was calcined in a muffle furnace at a heating rate of 10 °C / min, a calcination temperature of 550 °C, and a calcination time of 6 h to obtain the cerium-based support.

[0132] (2) Preparation of platinum nanoparticle solution: Weigh 465 mg Pt(NO3)2 (16.76 wt%) and 315 mg PVP

[0133] (k30) was completely dissolved in 9 mL and 24 mL of ethylene glycol. The two solutions were then mixed in a 100 mL three-necked flask. The reaction gas was first purged with N2, followed by heating to 120 °C and reacting for 5 h. The mixture was then washed by centrifugation with 9 times its volume of acetone, and finally dispersed in ethanol to obtain a platinum nanoparticle solution. The concentration of the nanoparticle solution was determined by ICP and controlled at 1 mg / mL.

[0134] (3) Preparation of platinum-cerium-based catalyst: Take 20 mL of platinum nanoparticle solution from step (2) and add it to 980 mg of the support obtained in step (1). Stir at room temperature for 4 h on an electromagnetic stirrer with a magnetic stirrer speed of 500 r / min. Then stir and dry at 50 °C. Finally, calcine at 600 °C for 8 h in a muffle furnace with a calcination heating rate of 3 °C / min to obtain the platinum-cerium-based catalyst.

[0135] Example 10

[0136] This embodiment provides a platinum-cerium-based catalyst, wherein the Pt9Ru1 loading is 1 wt% and the molar percentage of bismuth surface vacancy regulator in the cerium-based support is 10%.

[0137] The preparation method of the platinum-cerium-based catalyst is the same as that of Example 2, except that the method for preparing the platinum nanoparticle solution in step (2) is different from that in Example 1.

[0138] The method for preparing the platinum nanoparticle solution in step (2) of this embodiment includes:

[0139] Preparation of platinum nanoparticle solution: 418 mg Pt(NO3)2 (16.76 wt%) and 95 mg RuCl3 were dissolved in 9 mL of ethylene glycol, and 315 mg PVP(k30) was dissolved in 24 mL of ethylene glycol. The two solutions were then mixed in a 100 mL three-necked flask. The reaction gas was first purged with N2, and then heated to 120 °C for 5 h. Afterward, the mixture was washed with 9 times its volume of acetone by centrifugation, and finally dispersed with ethanol to obtain a Pt9Ru1 nanoparticle solution. The concentration of the nanoparticle solution was determined by ICP and controlled at 2.5 mg / mL.

[0140] Example 11

[0141] This embodiment provides a platinum-cerium-based catalyst, wherein the loading of the platinum-based redox component is 1 wt%, and the molar percentage of the bismuth surface vacancy regulator in the cerium-based support is 10%.

[0142] The preparation method of the platinum-cerium-based catalyst is the same as in Example 1, except that in step (1), 2.3158g of cerium nitrate hexahydrate, 0.5g of alumina and 0.2856g of bismuth nitrate pentahydrate are weighed and completely dissolved in 30mL of HNO3 with a molar concentration of 2mol / L.

[0143] Example 12

[0144] This embodiment provides a platinum-cerium-based catalyst, wherein the loading of the platinum-based redox component is 1 wt%, and the molar percentage of the bismuth surface vacancy regulator in the cerium-based support is 5%.

[0145] The preparation method of the platinum-cerium-based catalyst is the same as in Example 1, except that in step (1), 2.4444 g of cerium nitrate hexahydrate and 0.1437 g of bismuth nitrate pentahydrate are weighed and completely dissolved in 30 mL of HNO3 with a molar concentration of 2 mol / L.

[0146] Example 13

[0147] This embodiment provides a platinum-cerium-based catalyst, wherein the loading of the platinum-based redox component is 1 wt%, and the molar percentage of the bismuth surface vacancy regulator in the cerium-based support is 5%.

[0148] The preparation method of the platinum-cerium-based catalyst is the same as in Example 2, except that in step (1), 2.4444 g of cerium nitrate hexahydrate and 0.1437 g of bismuth nitrate pentahydrate are weighed and completely dissolved in 30 mL of HNO3 with a molar concentration of 2 mol / L.

[0149] Example 14

[0150] This embodiment provides a platinum-cerium-based catalyst, wherein the loading of the platinum-based redox component is 1 wt%, and the molar percentage of the bismuth surface vacancy regulator in the cerium-based support is 35%.

[0151] The preparation method of the platinum-cerium-based catalyst is the same as in Example 1, except that in step (1), 2.5087 g of cerium nitrate hexahydrate and 1.4994 g of bismuth nitrate pentahydrate are weighed and completely dissolved in 30 mL of HNO3 with a molar concentration of 2 mol / L.

[0152] Example 15

[0153] This embodiment provides a platinum-cerium-based catalyst, wherein the loading of the platinum-based redox component is 0.05 wt%, and the molar percentage of the bismuth surface vacancy regulator in the cerium-based support is 10%.

[0154] The preparation method of the platinum-cerium-based catalyst is the same as in Example 1, except that in step (3) 0.2 mL of the platinum solution from step (2) is added to 999.5 mg of the support obtained in step (1).

[0155] Example 16

[0156] This embodiment provides a platinum-cerium-based catalyst, wherein the loading of the platinum-based redox component is 6 wt%, and the molar percentage of the bismuth surface vacancy regulator in the cerium-based support is 10%.

[0157] The preparation method of the platinum-cerium-based catalyst is the same as in Example 1, except that in step (3) 24 mL of the platinum solution from step (2) is added to 940 mg of the carrier obtained in step (1).

[0158] Example 17

[0159] This embodiment provides a platinum-cerium-based catalyst, wherein the loading of the platinum-based redox component is 1 wt%, and the molar percentage of the neodymium surface vacancy regulator in the cerium-based support is 10%.

[0160] The preparation method of the platinum-cerium-based catalyst is the same as that in Example 1, except that the calcination temperature in step (3) is 700℃.

[0161] Comparative Example 1

[0162] This comparative example provides a platinum-cerium-based catalyst, wherein the loading of the platinum-based redox component is 1 wt%, and the cerium-based support does not contain a surface vacancy modifier.

[0163] The preparation method of the platinum-cerium-based catalyst is the same as that in Example 1, except that bismuth nitrate pentahydrate is not added in step (1).

[0164] Comparative Example 2

[0165] This comparative example provides a platinum-cerium-based catalyst, wherein the loading of the platinum-based redox component is 1 wt%, and the cerium-based support does not contain a surface vacancy modifier.

[0166] The preparation method of the platinum-cerium-based catalyst is the same as that in Example 2, except that bismuth nitrate pentahydrate is not added in step (1).

[0167] Comparative Example 3

[0168] This comparative example provides a cerium-based catalyst that is not platinum-supported, wherein the molar percentage of bismuth surface vacancy modifier in the cerium-based support is 10%.

[0169] The preparation method of the cerium-based catalyst is the same as that in Example 1, except that step (2) is omitted and step (3) does not involve the addition of platinum nanoparticle solution.

[0170] Performance testing:

[0171] The conversion rates of catalytic carbon monoxide combustion at different temperatures were tested for the catalysts provided in all the above embodiments and comparative examples.

[0172] Test method: Weigh a certain amount of catalyst and mix it with 180 mg of quartz sand, then place it in a quartz tube to determine its reactivity.

[0173] Measurement conditions: For a space velocity (SV) of 150,000 mL / (h·g), the total flow rate was 50 mL / min, and the catalyst mass was 20 mg; for a space velocity (SV) of 30,000 mL / (h·g), the total flow rate was 25 mL / min, and the catalyst mass was 50 mg.

[0174] The reactant gases consist of 0.5 vol% CO and 10 vol% O2, with nitrogen as the balance gas. The CO concentration in the tail gas is monitored using a GC-2060 gas chromatograph (FID detector). The catalyst's CO conversion efficiency is calculated using the following formula: R = (C0 - C1) / C0 × 100%, where R is the CO conversion rate, C0 is the CO concentration in the inlet reactant gas, C1 is the CO concentration in the outlet reactant gas, and the temperature points corresponding to CO conversion rates of 50% and ~100% (i.e., T) are used. 50 T 100 To evaluate the activity of the catalyst.

[0175] The test results are shown in Table 1 (30000 mL / (h·g)) and Table 2 (150000 mL / (h·g)). Figure 1 and Figure 2 As shown, ΔT in Table 1 50 T for samples prepared at 500℃ and samples prepared at 400℃ 50 Difference, ΔT in Table 2 50 Samples prepared at 500℃ and T of Comparative Example 1 50 Difference.

[0176] The platinum-cerium-based catalysts prepared in Examples 1-2 and Comparative Examples 1-2 were subjected to in-situ carbon monoxide adsorption-desorption infrared spectroscopy.

[0177] The test method was as follows: The sample was first heated at 300℃ for 1 hour under a nitrogen atmosphere (30 mL / min). After the sample cell cooled to 30℃, the background spectrum was collected. Then, 5% CO / N2 (30 mL / min) was introduced for adsorption-desorption infrared spectroscopy. The test results are shown below. Figures 3-6 .

[0178] XPS tests were performed on the platinum-cerium-based catalysts prepared in Examples 1-2 and Comparative Examples 1-2. The test results for Examples 1 and Comparative Examples 1 are shown in the figure. Figures 7-8 The test results of Example 2 and Comparative Example 2 are shown in [the table]. Figures 9-10 .

[0179] The platinum-cerium-based catalysts prepared in Example 1 and Comparative Example 1 were subjected to CO2 desorption programmed tests. The test results are shown in [Figure 1]. Figure 11 .

[0180] The platinum-cerium-based catalysts prepared in Example 2 and Comparative Example 2 were subjected to aberration-corrected electron microscopy (SEM) analysis. The SEM images are shown below. Figures 12-13 .

[0181] Table 1

[0182] Example 1 2.5 117 125 - Example 2 1.8 118 125 1 Example 3 2.4 115 125 - Example 4 2.0 125 135 10 Example 5 2.5 120 127 - Example 6 2.0 131 139 11 Example 11 2.4 122 131 - Example 12 1.5 128 135 - Example 13 - 158 165 30 Example 14 2.5 139 143 - Example 15 - 155 163 - Example 16 2.9 120 131 - Example 17 - 228 240 - Comparative Example 1 1.5 123 130 - Comparative Example 2 - 158 165 35

[0183] Table 2

[0184] Example 2 1.8 149 165 26 Example 4 2.0 152 165 23 Example 6 2.0 152 165 23 Example 7 1.9 154 169 21 Example 8 1.8 155 170 20 Example 9 2.0 154 172 21 Example 10 2.2 145 161 30 Example 13 - 175 185 - Comparative Example 2 - 175 185 0 Comparative Example 3 - 350 420 -

[0185] This invention introduces a surface vacancy regulator into a platinum-cerium-based catalyst to change the alkalinity, oxygen vacancy concentration, and cerium vacancy concentration on the surface of the cerium-based support, thereby weakening the strong interaction between the platinum-based redox components and the cerium-based support. This enables the stable existence of platinum nanoclusters under high-temperature oxidation conditions and significantly improves the stability and catalytic activity of the platinum-cerium-based catalyst.

[0186] Based on the test results of the conversion rate of catalytic carbon monoxide combustion in Examples 1-11, the introduction of surface vacancy regulators can reduce the Lewis base content and strength on the surface of cerium-based supports, increase the surface oxygen vacancy concentration and reduce the cerium vacancy concentration, thereby weakening the strong interaction between the support and the redox components, thus preparing cerium-based supports. Based on the effect of surface vacancy regulators, after high-temperature calcination, the platinum-based redox components can still maintain the platinum nanocluster distribution, thereby maintaining their original activity.

[0187] Based on the test results of the conversion rate of catalytic carbon monoxide combustion in Examples 1-2 and Comparative Examples 1-2, it is found that without the introduction of a surface modifier, the distribution of platinum nanoclusters cannot be maintained, resulting in a decrease in the activity of the platinum-supported cerium-based catalyst.

[0188] Based on the test results of the conversion rate of catalytic carbon monoxide combustion in Examples 1 and 12-14, the amount of surface vacancy regulator added should be within a suitable range. Too low an amount will not be able to resist the tendency of platinum nanoclusters to disperse into single atoms, while too high an amount will introduce a higher concentration of oxygen vacancies and inhibit the activation oxygen ability of the cerium-based support.

[0189] Based on the test results of the conversion rate of catalytic carbon monoxide combustion in Examples 1 and 15-16, if the loading of platinum-based redox components is too low, platinum single atoms are easily formed; if the loading is too high, the utilization rate of platinum atoms is low.

[0190] Based on the test results of the conversion rate of catalytic carbon monoxide combustion in Examples 1 and 17, if the calcination temperature in step (3) is too high, the surface of the platinum nanoclusters will be partially oxidized or dispersed on the support surface to form single atoms, and the activity will be relatively poor.

[0191] from Figure 3 The in-situ carbon monoxide indices of the platinum-cerium-based catalysts in Example 1 and Comparative Example 1 show that the platinum-cerium-based catalyst prepared in Example 1 exhibits higher carbon monoxide content at 2050 cm⁻¹. -1A distinct tailing phenomenon is observed in the left and right regions. The peaks in this region can be attributed to the linear adsorption of CO molecules on metallic platinum, indicating that the introduction of Bi is beneficial for maintaining the cluster morphology of platinum at 500℃. In contrast, the platinum-cerium-based catalyst prepared in Comparative Example 1 shows a peak at 2092 cm⁻¹. -1 A symmetrical narrow peak appeared, which represents the linear adsorption of CO molecules on isolated single-atom platinum sites, indicating that platinum atoms are atomically dispersed on the platinum / CeO2 surface.

[0192] Figures 4-7 The XPS test results show that the lattice oxygen ratio in the platinum-cerium-based catalysts prepared in Examples 1 and 2 is ~68%, while the lattice oxygen ratio in the platinum-cerium-based catalysts prepared in Comparative Examples 1 and 2 is ~76%. This indicates that the doping of the surface vacancy regulator effectively reduces the strength and content of the alkali on the support surface, as well as the proportion of low-coordinated O, which is beneficial to maintaining the stable distribution of platinum nanoclusters on the cerium-based support surface.

[0193] from Figure 6 The CO2 desorption program curves of the cerium-based catalysts prepared in the examples and Comparative Example 1 show that the CO2 adsorption capacity of the cerium-based catalyst in Example 1 is significantly less than that in Comparative Example 1, and a significant signal peak only appears at 455℃. This peak can be attributed to the desorption peak of CO2 by a moderately strong base. In contrast, the cerium-based catalyst in Comparative Example 1 shows a significant peak at >500℃. This peak, for strong base sites, can be attributed to the desorption peak of CO2 by low-coordinate O on the support surface. This further illustrates that the doping of the surface vacancy regulator effectively reduces the strength and content of the base on the support surface, as well as the proportion of low-coordinate O, which is beneficial to maintaining the stable distribution of platinum nanoclusters on the cerium-based support surface.

[0194] The applicant declares that the above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. A platinum-cerium-based catalyst, characterized in that, The platinum-cerium-based catalyst comprises a cerium-based support and a platinum-based redox component distributed on the surface of the cerium-based support; The platinum-based redox component includes platinum nanoclusters; The cerium-based support includes a surface vacancy modifier, which is neodymium or bismuth. The preparation method of the platinum-cerium-based catalyst includes: A mixed solution is obtained by mixing a cerium source, a surface vacancy regulator precursor, and a solvent. The solution is then reacted to obtain a cerium-based support precursor. The cerium-based support precursor is then calcined to obtain the cerium-based support. A solution of cerium-based support and platinum-based nanoparticles was mixed and dried to obtain a platinum-cerium-based catalyst precursor. The platinum-cerium-based catalyst precursor was then calcined to obtain the platinum-cerium-based catalyst. The calcination temperature of the platinum-cerium-based catalyst precursor is 400℃-450℃; In the cerium-based support, the molar percentage of the surface vacancy regulator is 10%-12%; In the platinum-cerium-based catalyst, the mass percentage of the platinum-based redox component is 0.5%-4.5%.

2. The platinum-cerium based catalyst as described in claim 1, characterized in that, The average size of the platinum nanoclusters is 1 nm to 5 nm.

3. The platinum-cerium based catalyst as described in claim 1, characterized in that, The average size of the platinum nanoclusters is 1 nm to 3 nm.

4. The platinum-cerium based catalyst according to claim 1, characterized in that, In the platinum-cerium-based catalyst, the mass percentage of the platinum-based redox component is 0.5%-1%.

5. The platinum-cerium based catalyst as described in claim 1, characterized in that, The platinum-based redox component also includes a second metal.

6. The platinum-cerium based catalyst according to claim 5, characterized in that, The second metal includes any one or a combination of at least two of Pd, Ru, or Ir.

7. The platinum-cerium based catalyst according to claim 5, characterized in that, The mass percentage of the second metal is ≤30%.

8. The platinum-cerium based catalyst according to claim 1, characterized in that, The cerium-based support also includes metal oxides.

9. The platinum-cerium based catalyst as described in claim 8, characterized in that, The mass percentage of metal oxides in the cerium-based support is ≤20%.

10. The platinum-cerium based catalyst as described in claim 8, characterized in that, The metal oxide includes any one or a combination of at least two of aluminum oxide, manganese dioxide, titanium dioxide, cobalt oxide, nickel oxide, or copper oxide.

11. A method for preparing a platinum-cerium-based catalyst as described in any one of claims 1-10, characterized in that, The preparation method includes: A mixed solution is obtained by mixing a cerium source, a surface vacancy regulator precursor, and a solvent. The solution is then reacted to obtain a cerium-based support precursor. The cerium-based support precursor is then calcined to obtain a cerium-based support. A solution of cerium-based support and platinum-based nanoparticles was mixed and dried to obtain a platinum-cerium-based catalyst precursor. The platinum-cerium-based catalyst precursor was then calcined to obtain the platinum-cerium-based catalyst. The calcination temperature of the platinum-cerium-based catalyst precursor is 400℃-450℃.

12. The preparation method according to claim 11, characterized in that, In the mixed solution, the concentrations of the cerium source and the surface vacancy regulator precursor are each independently 0.1 mmol / mL to 0.5 mmol / mL.

13. The preparation method according to claim 11, characterized in that, The molar ratio of cerium source to surface vacancy regulator precursor in the mixed solution is (88-90):(10-12).

14. The preparation method according to claim 11, characterized in that, The cerium source includes any one or a combination of two of cerium nitrate or cerium chloride.

15. The preparation method according to claim 11, characterized in that, The surface vacancy regulator precursor is a neodymium salt or a bismuth salt.

16. The preparation method according to claim 15, characterized in that, The surface vacancy regulator precursor is neodymium nitrate or bismuth nitrate.

17. The preparation method according to claim 11, characterized in that, The solvent includes water and / or ethanol.

18. The preparation method according to claim 11, characterized in that, The method for obtaining the cerium-based support precursor by the reaction includes any one of the following: chemical coprecipitation, hydrothermal method, or sol-gel method.

19. The preparation method according to claim 11, characterized in that, The method for preparing the cerium-based support also includes aging and drying the cerium-based support precursor obtained from the reaction.

20. The preparation method according to claim 19, characterized in that, The aging temperature is 20℃-40℃.

21. The preparation method according to claim 19, characterized in that, The aging time is 4h-12h.

22. The preparation method according to claim 19, characterized in that, The drying temperature is 60℃-100℃.

23. The preparation method according to claim 11, characterized in that, The calcination temperature of the cerium-based support precursor is 500℃-600℃.

24. The preparation method according to claim 11, characterized in that, The calcination time of the cerium-based support precursor is 3-6 hours.

25. The preparation method according to claim 11, characterized in that, The heating rate for calcining the cerium-based support precursor is 2℃ / min-10℃ / min.

26. The preparation method according to claim 11, characterized in that, The concentration of platinum-based nanoparticles in the platinum-based nanoparticle solution is 1 mg / mL to 3 mg / mL.

27. The preparation method according to claim 11, characterized in that, The platinum-based nanoparticles were prepared by reducing a platinum-based precursor.

28. The preparation method according to claim 27, characterized in that, The platinum-based precursor includes a platinum salt and a second metal salt.

29. The preparation method according to claim 28, characterized in that, The platinum salt includes any one or a combination of at least two of platinum nitrate, platinum acetylacetonate, platinum chloride, or platinum acetate.

30. The preparation method according to claim 28, characterized in that, The second metal salt shown includes any one or a combination of at least two of Pd, Ru, or Ir salts.

31. The preparation method according to claim 30, characterized in that, The Pd salt includes palladium nitrate and / or palladium chloride.

32. The preparation method according to claim 30, characterized in that, The Ru salt includes ruthenium chloride and / or ruthenium acetate.

33. The preparation method according to claim 30, characterized in that, The Ir salt includes any one or a combination of at least two of iridium trichloride, ammonium iridate, or iridium tetrachloride.

34. The preparation method according to claim 27, characterized in that, The method of reducing the platinum-based precursor includes any one of the following: ethylene glycol reduction, ethanol reduction, or sodium borohydride reduction.

35. The preparation method according to claim 11, characterized in that, The method of mixing the cerium-based support with the platinum-based nanoparticle solution includes stirring.

36. The preparation method according to claim 35, characterized in that, The stirring rate is 300 r / min-800 r / min.

37. The preparation method according to claim 35, characterized in that, The stirring time is 2-4 hours.

38. The preparation method according to claim 11, characterized in that, The drying temperature for obtaining the platinum-cerium-based catalyst precursor is 50℃-80℃.

39. The preparation method according to claim 11, characterized in that, The calcination time of the platinum-cerium-based catalyst precursor is 4h-12h.

40. The preparation method according to claim 11, characterized in that, The heating rate for calcining the platinum-cerium-based catalyst precursor is 2℃ / min-5℃ / min.

41. The application of the platinum-cerium based catalyst according to any one of claims 1-10, characterized in that, The platinum-cerium-based catalyst is used for the catalytic oxidative removal of gaseous pollutants.

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