Pd-coated In2S3 composite formic acid hydrogen production catalyst and preparation method thereof
By preparing pd@In2S3 composite catalyst, the problems of cumbersome preparation process and low catalytic efficiency are solved, and the effects of simplifying the process and improving the catalytic efficiency are achieved, and the potential for industrial application is great.
Patent Information
- Application Number
- CN202411917180.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-24
- Publication Date
- 2025-03-28
AI Technical Summary
The existing catalysts used for hydrogen production of formic acid are cumbersome, with high preparation temperature and low catalytic efficiency.
Using the preparation method of pd@In2S3 composite formic acid hydrogen production catalyst, In2S3 is prepared and immersed in a palladium-containing metal precursor solution, and the catalyst is obtained after reduction and grinding.
The catalyst preparation process is simplified, the reaction conditions are mild, and the catalytic efficiency is improved, and there is a great prospect for industrial application.
Smart Images
Figure CN119702007A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of catalyst technology, and in particular to a Pd@In2S3 composite formic acid hydrogen production catalyst and a preparation method thereof. Background Art
[0002] With the rapid development of the global economy, traditional fossil energy has caused serious environmental pollution problems. It is urgent to change the dependence on the traditional fossil energy system and establish a green energy structure. The energy structure is shifting towards high energy density "zero emission" energy carriers (hydrogen).
[0003] Formic acid (HCOOH) is the simplest hydrogen-containing monobasic organic carboxylic acid. The Gibbs free energy of the formic acid decomposition reaction to produce hydrogen at room temperature is negative, that is, it is thermodynamically favorable. Compared with other hydrogen carriers (such as methanol, ammonia, etc.), which all rely on high temperature, high pressure and catalyst-catalyzed reaction conditions to decompose and produce hydrogen, formic acid can be efficiently decomposed into hydrogen and carbon dioxide at room temperature and pressure under the action of a catalyst. Therefore, formic acid hydrogen production is one of the most feasible hydrogen production methods at this stage. The widespread application of hydrogen energy faces an important bottleneck problem, namely the difficulty in safe and efficient storage and transportation of hydrogen. The main storage and transportation process of hydrogen is to transport gaseous or liquid hydrogen through special high-pressure storage tanks or pipelines. Although the technology is relatively mature, it requires specific low temperature or high pressure conditions, which not only increases energy consumption and cost, but also poses considerable challenges to safety. As a current research hotspot, photocatalytic formic acid hydrogen production is of paramount importance in preparing efficient catalysts with a simple and quick method.
[0004] At present, many catalysts with excellent activity for producing hydrogen from formic acid have complicated preparation processes, high preparation temperatures, and low catalytic efficiency. Summary of the invention
[0005] The present application provides a pd@In2S3 composite formic acid hydrogen production catalyst and a preparation method thereof, which solves the problem that the catalyst with excellent activity for formic acid hydrogen production in the prior art has a relatively complicated preparation process, a high preparation temperature and low catalytic efficiency.
[0006] An embodiment of the present invention provides a method for preparing a pd@In2S3 composite formic acid hydrogen production catalyst, comprising the following steps: preparing In2S3; immersing the prepared In2S3 in a solution containing a palladium metal precursor, and after taking it out, obtaining a reduced product; and grinding the reduced product to obtain a pd@In2S3 composite formic acid hydrogen production catalyst.
[0007] In a possible implementation, the preparation of In2S3 includes using In(NO3)3·xH2O and a sulfur source to prepare In2S according to a hydrothermal method. 3。
[0008] In a possible implementation, In(NO3)3·xH2O and a sulfur source are used to prepare In2S3 by a hydrothermal method; comprising: weighing 2mmol-4mmol In(NO3)3·xH2O and 4mmol-6mmol sulfur source respectively and preparing In2S3 by a hydrothermal method.
[0009] In a possible implementation, the hydrothermal method comprises the following steps:
[0010] S11: After mixing In(NO3)3·xH2O and the sulfur source, add ethanol or distilled water solution, mix well and place in a magnetic stirrer for stirring;
[0011] S12: The suspension is placed in a stainless steel autoclave for solvothermal reaction. After cooling to room temperature, the suspension is washed three times by centrifugation with distilled water and anhydrous ethanol. After drying and grinding, In2S3 is obtained for later use.
[0012] In a possible implementation, step S11 includes adding 100 ml of ethanol or distilled water solution with a volume ratio of 1:1 after mixing In(NO3)3·xH2O and the sulfur source, mixing evenly and placing in a magnetic stirrer and stirring at a speed of 500 r / min for 30 min.
[0013] In a possible implementation, step S12 includes placing the suspension in a stainless steel autoclave for a 180°C solvothermal reaction for 12 hours, cooling to room temperature, centrifugally washing three times with distilled water and anhydrous ethanol, vacuum drying at 60°C for 12 hours, and then grinding with a mortar to obtain In2S3 for use.
[0014] In one possible implementation, the prepared In2S3 is immersed in a solution containing a palladium (Pd) metal precursor, and after taking it out, a reduced product is obtained; including: immersing 3.25g In2S3 in a solution containing a palladium metal precursor, controlling the immersion time for 5h-12h, drying at 80 degrees Celsius for 8h, heating at a rate of 10°C / min in a N2 atmosphere, reducing at 500°C for 2h-4h, cooling the sample to room temperature under a N2 flow, and taking it out to obtain a reduced black product.
[0015] In a possible implementation, the sulfur source includes thiourea, thioacetamide and L-cysteine.
[0016] In a possible implementation, the palladium metal precursor includes Pd(NO3)2, palladium chloride and chloropalladic acid.
[0017] In a possible implementation, the molar ratio of the In2S3 to the palladium metal precursor is 2:1-2.
[0018] One or more technical solutions provided in the embodiments of the present invention have at least the following technical effects:
[0019] The embodiment of the present invention adopts a preparation method of a pd@In2S3 composite formic acid hydrogen production catalyst, including the following steps: preparing In2S3; immersing the prepared In2S3 in a solution containing a palladium metal precursor, and obtaining a reduced product after taking it out; grinding the reduced product to obtain a pd@In2S3 composite formic acid hydrogen production catalyst. Among them, the three-dimensional In2S3 provides a good carrier effect for the pd precious metal, which improves the catalytic efficiency to a certain extent; after the In2S3 is composited with the pd precious metal, it not only promotes the catalytic efficiency of pd, but also simplifies the entire preparation process, making the reaction conditions mild, and has great prospects for industrial application. The present application solves the problem of the catalyst with excellent activity used for formic acid hydrogen production in the prior art, and its preparation process is relatively cumbersome. There is a defect of high preparation temperature, and there is also a problem of low catalytic efficiency. The technical effect of simplifying the preparation process, making the reaction conditions mild, and improving the catalytic efficiency is achieved, and it has great prospects for industrial application. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments of the present application. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.
[0021] Figure 1 TEM image of the pd@In2S3 composite formic acid hydrogen production catalyst provided in the examples of the present application;
[0022] Figure 2 TEM image of the pd@In2S3 composite formic acid hydrogen production catalyst provided in the examples of the present application;
[0023] Figure 3 TEM image of the pd@In2S3 composite formic acid hydrogen production catalyst provided in the examples of the present application;
[0024] Figure 4 The hydrogen selectivity of the pd@In2S3 composite formic acid hydrogen production catalyst provided in the embodiment of the present application;
[0025] Figure 5 The formic acid conversion rate of the pd@In2S3 composite formic acid hydrogen production catalyst provided in the embodiment of the present application;
[0026] Figure 6 This is the hydrogen generation rate of the pd@In2S3 composite formic acid hydrogen production catalyst provided in the embodiments of the present application. DETAILED DESCRIPTION
[0027] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.
[0028] In the description of the embodiments of the present application, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limitations on the present application. The terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance. In addition, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.
[0029] An embodiment of the present invention provides a method for preparing a pd@In2S3 composite formic acid hydrogen production catalyst, comprising the following steps: preparing In2S3; immersing the prepared In2S3 in a solution containing a palladium metal precursor, and after taking it out, obtaining a reduced product; and grinding the reduced product to obtain a pd@In2S3 composite formic acid hydrogen production catalyst.
[0030] Illustratively, the chemical formula of palladium is Pd.
[0031] In an embodiment of the present application, the preparation of In2S3 includes using In(NO3)3·xH2O and a sulfur source and preparing In2S3 according to a hydrothermal method.
[0032] In an embodiment of the present application, In(NO3)3·xH2O and a sulfur source are used to prepare In2S3 by a hydrothermal method; the method comprises: weighing 2mmol-4mmol In(NO3)3·xH2O and 4mmol-6mmol sulfur source respectively and preparing In2S3 by a hydrothermal method.
[0033] In the embodiment of the present application, the hydrothermal method comprises the following steps:
[0034] S11: After mixing In(NO3)3·xH2O and the sulfur source, add ethanol or distilled water solution, mix well and place in a magnetic stirrer for stirring;
[0035] S12: The suspension is placed in a stainless steel autoclave for solvothermal reaction. After cooling to room temperature, the suspension is washed three times by centrifugation with distilled water and anhydrous ethanol. After drying and grinding, In2S3 is obtained for later use.
[0036] In the embodiment of the present application, step S11 includes adding 100 ml of ethanol or distilled water solution with a volume ratio of 1:1 after mixing In(NO3)3·xH2O and the sulfur source, mixing evenly and placing in a magnetic stirrer and stirring at a speed of 500 r / min for 30 minutes.
[0037] In the embodiment of the present application, step S12 includes placing the suspension in a stainless steel autoclave for a 180°C solvent thermal reaction for 12 hours, cooling to room temperature, centrifugally washing three times with distilled water and anhydrous ethanol, vacuum drying at 60°C for 12 hours, and then grinding with a mortar to obtain In2S3 for use.
[0038] In an embodiment of the present application, the prepared In2S3 is immersed in a solution containing a palladium metal precursor, and after taking it out, a reduced product is obtained; including: immersing 3.25g In2S3 in a solution containing a palladium metal precursor, controlling the immersion time for 5h-12h, drying at 80 degrees Celsius for 8h, heating at a rate of 10°C / min under a N2 atmosphere, reducing at 500°C for 2h-4h, waiting for the sample to cool to room temperature under a N2 flow, and taking it out to obtain a reduced black product.
[0039] In the examples of the present application, the sulfur source includes thiourea, thioacetamide and L-cysteine.
[0040] For example, the chemical formula of thiourea is H2NCSNH2, the chemical formula of thioacetamide is CH3CSNH2, and the chemical formula of L-cysteine is C3H7NO2S.
[0041] In the embodiment of the present application, the palladium metal precursor in step S1 includes Pd(NO3)2, palladium chloride and chloropalladic acid.
[0042] In the embodiment of the present application, the molar ratio of In2S3 to the palladium metal precursor is 2:1-2.
[0043] Embodiment 1:
[0044] The present invention provides a method for preparing a pd@In2S3 composite formic acid hydrogen production catalyst, such as Figure 1As shown, 3mmolIn(NO3)3·xH2O and 5mmolthiourea were weighed in a beaker, and then 100ml of ethanol or distilled water solution with a volume ratio of 1:1 was added. After mixing evenly, the mixture was placed in a magnetic stirrer and stirred at 500r / min for 30min. The suspension was then placed in a stainless steel autoclave with a polytetrafluoroethylene liner for a 180℃ solvothermal reaction for 12h. After cooling to room temperature, it was centrifuged and washed three times with distilled water and anhydrous ethanol, dried at 60℃ in a vacuum for 12h, and ground with a mortar for use. 3.25g In2S3 was immersed in 100ml2.3g Pd(NO3)2 solution, stirred evenly, immersed for 12h, dried at 80℃ for 8h, heated at a rate of 10℃ / min in a N2 atmosphere, reduced at 500℃ for 2h, and the sample was cooled to room temperature under N2 flow and taken out. The reduced black product was ground to obtain a pd@In2S3 composite formic acid hydrogen production catalyst.
[0045] Embodiment 2:
[0046] The present invention provides a method for preparing a pd@In2S3 composite formic acid hydrogen production catalyst, such as Figure 2 As shown, 3mmol In(NO3)3·xH2O and 5mmol thioacetamide were weighed in a beaker, and then 100ml of ethanol or distilled water solution with a volume ratio of 1:1 was added. After mixing evenly, it was placed in a magnetic stirrer and stirred at 500r / min for 30min. The suspension was then placed in a stainless steel autoclave with a polytetrafluoroethylene liner for a 180℃ solvothermal reaction for 12h. After cooling to room temperature, it was centrifuged and washed three times with distilled water and anhydrous ethanol, dried at 60℃ in a vacuum for 12h, and ground with a mortar for use. 3.25g In2S3 was immersed in 100ml 2.3g Pd(NO3)2 solution, stirred evenly, immersed for 12h, dried at 80℃ for 8h, heated at a rate of 10℃ / min in a N2 atmosphere, reduced at 500℃ for 2h, and the sample was cooled to room temperature under N2 flow and taken out. The reduced black product was ground to obtain a pd@In2S3 composite formic acid hydrogen production catalyst.
[0047] Embodiment 3:
[0048] The present invention provides a method for preparing a pd@In2S3 composite formic acid hydrogen production catalyst, such as Figure 3As shown, 3mmol In(NO3)3·xH2O and 5mmol L-cysteine were weighed in a beaker, and then 100ml of ethanol or distilled water solution with a volume ratio of 1:1 was added. After mixing evenly, it was placed in a magnetic stirrer and stirred at 500r / min for 30min. The suspension was then placed in a stainless steel autoclave with a polytetrafluoroethylene liner for a 180℃ solvothermal reaction for 12h. After cooling to room temperature, it was centrifuged and washed three times with distilled water and anhydrous ethanol, dried at 60℃ in a vacuum for 12h, and ground with a mortar for use. 3.25g In2S3 was immersed in 100ml 0.9g palladium chloride solution, stirred evenly, immersed for 12h, dried at 80℃ for 8h, heated at a rate of 10℃ / min in a N2 atmosphere, reduced at 500℃ for 2h, and the sample was cooled to room temperature under N2 flow and taken out. The reduced black product was ground to obtain a pd@In2S3 composite formic acid hydrogen production catalyst.
[0049] like Figure 1-3 As shown in the figure, the In2S3 prepared with In(NO3)3·xH2O as the indium source and TAA (thioacetamide) as the sulfur source is composed of many irregular nanoparticles, and the overall particle size radius is about 3μm; while the In2S3 synthesized with L-cysteine as the sulfur source presents classic micron-spheres formed by the accumulation of nanosheets, and the size of the micron-spheres is about 5-6μm; the In2S3 synthesized hydrothermally using thiourea as the sulfur source also presents an irregular plate-like morphology with a relatively smooth surface.
[0050] like Figure 4 As shown, the hydrogen selectivities of Examples 1-3 are 89.2%, 97.5%, and 85.6%, respectively, among which Example 2 has the best hydrogen selectivity of 97.5%.
[0051] like Figure 5 As shown, the formic acid conversion rates of Examples 1-3 are 90.5%, 99.2% and 88.5%, respectively, among which Example 2 has the best formic acid conversion rate of 99.2%.
[0052] like Figure 6 As shown, the formic acid conversion rates of Examples 1-3 are 340 mmol / (g·h), 435 mmol / (g·h) and 230 mmol / (g·h), respectively, among which Example 2 has the best formic acid conversion rate of 435 mmol / (g·h).
[0053] The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referenced to each other. Each embodiment focuses on the differences from other embodiments.
[0054] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit the present application. Although the present application has been described in detail with reference to the aforementioned embodiments, a person of ordinary skill in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some or all of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the present application.
Claims
1. A method for preparing a pd@In2S3 composite formic acid hydrogen production catalyst, characterized in that: The steps include: Preparation of In2S3; The prepared In2S3 is immersed in a solution containing a palladium metal precursor, and after being taken out, a reduced product is obtained; The product after grinding and reduction was obtained as Pd@In2S3 composite formic acid hydrogen production catalyst.
2. The method for preparing the pd@In2S3 composite formic acid hydrogen production catalyst according to claim 1, characterized in that: The preparation of In2S3 includes using In(NO3)3·xH2O and a sulfur source and preparing In2S according to a hydrothermal method 3。 3. The method for preparing the pd@In2S3 composite formic acid hydrogen production catalyst according to claim 2, characterized in that: In2S3 was prepared by a hydrothermal method using In(NO3)3·xH2O and a sulfur source; The method comprises: weighing 2mmol-4mmol In(NO3)3·xH2O and 4mmol-6mmol sulfur source respectively and preparing In2S3 according to a hydrothermal method.
4. The method for preparing the pd@In2S3 composite formic acid hydrogen production catalyst according to claim 2, characterized in that: The hydrothermal method comprises the following steps: S11: After mixing In(NO3)3·xH2O and the sulfur source, add ethanol or distilled water solution, mix well and place in a magnetic stirrer for stirring; S12: The suspension was placed in a stainless steel autoclave for solvothermal reaction. After cooling to room temperature, the suspension was centrifugally washed three times with distilled water and anhydrous ethanol, and then dried and ground to obtain In2S3.
5. The method for preparing the pd@In2S3 composite formic acid hydrogen production catalyst according to claim 4, characterized in that: The step S11 includes adding 100 ml of ethanol or distilled water solution with a volume ratio of 1:1 after mixing In(NO3)3·xH2O and the sulfur source, mixing evenly and placing the mixture in a magnetic stirrer and stirring at a speed of 500 r / min for 30 minutes.
6. The method for preparing the pd@In2S3 composite formic acid hydrogen production catalyst according to claim 4, characterized in that: The step S12 comprises placing the suspension in a stainless steel autoclave for a solvothermal reaction at 180° C. for 12 hours, cooling to room temperature, washing three times with distilled water and anhydrous ethanol by centrifugation, and vacuum drying at 60° C. for 12 hours, and then grinding with a mortar to obtain In2S3 for later use.
7. The method for preparing the pd@In2S3 composite formic acid hydrogen production catalyst according to claim 1, characterized in that: The prepared In2S3 is immersed in a solution containing a palladium metal precursor, and after taking it out, a reduced product is obtained; including: immersing 3.25g In2S3 in a solution containing a palladium metal precursor, controlling the immersion time for 5h-12h, drying at 80 degrees Celsius for 8h, heating at a rate of 10°C / min in a N2 atmosphere, reducing at 500°C for 2h-4h, cooling the sample to room temperature under a N2 flow, and taking it out to obtain a reduced black product.
8. The method for preparing the pd@In2S3 composite formic acid hydrogen production catalyst according to claim 2, characterized in that: The sulfur sources include thiourea, thioacetamide and L-cysteine.
9. The method for preparing the pd@In2S3 composite formic acid hydrogen production catalyst according to claim 1, characterized in that: The palladium metal precursor includes Pd(NO3)2, palladium chloride and chloropalladic acid.
10. The method for preparing the pd@In2S3 composite formic acid hydrogen production catalyst according to claim 1, characterized in that: The molar ratio of the In2S3 to the palladium metal precursor is 2:1-2.