CN-122006776-A - Ti-based3C2TxPreparation method and application of ruthenium-embedded cobalt nitride-cobalt phosphide composite catalyst

Abstract

The invention discloses a preparation method of a Ti 3 C 2 T x -based ruthenium-embedded cobalt nitride-cobalt phosphide composite catalyst and an ammonia borane hydrolysis hydrogen liberation catalytic application. The method comprises the steps of taking Ti 3 C 2 T x nano-sheets as a carrier, mixing Co 2+ salt solution, ru 3+ salt solution and urea, refluxing at the temperature of 100 ℃ in N 2 air flow for 5h, enabling ions to be adsorbed on the carrier through electrostatic action and grow into RuCo-LDH/Ti 3 C 2 T x precursor in situ, then separating NaH 2 PO 2 ·H 2 O and the precursor into the upstream and downstream of a tube furnace, and enabling the RuCo-LDH to be derived into the Ru/CoN-CoP/Ti 3 C 2 T x composite catalyst through high temperature. The catalyst has hydrogen evolution conversion frequency up to 589.7 mol H2 ·mol Ru –1 ·min –1 and 298K, and still retains 80% of initial activity after 5 times of hydrolysis and hydrogen release. The preparation process is simple, convenient, controllable, environment-friendly, free of harsh conditions and complex equipment, easy for large-scale mass production, and capable of providing technical and theoretical support for active site regulation and carrier collaborative optimization of heterogeneous catalysis, and has important academic value and industrial application prospect.

Inventors

• WEI QIUHONG
• MA WEIMIN

Assignees

• 桂林信息科技学院

Dates

Publication Date

20260512

Application Date

20260205

Claims (6)

1. 1. A preparation method of a ruthenium-embedded cobalt nitride-cobalt phosphide composite catalyst based on Ti 3 C 2 T x is characterized by comprising the following steps: s1, adding Co (NO 3 ) 2 ·6H 2 O、RuCl 3 ·nH 2 O and urea into deionized water, performing ultrasonic treatment for 20-40 min, and magnetically stirring until the Co is completely dissolved to obtain a solution A; S2, mixing a Ti 3 C 2 T x solution and an N-dimethyl pyrrolidone solution according to a volume ratio, adding polyethylene glycol 2000 with a mass fraction of 3-5% as a dispersing agent, and stirring at room temperature for 1-2 hours to obtain a dispersion modified solution B; S3, dropwise adding the solution A obtained in the step S1 into the solution B obtained in the step S2 under the condition of room temperature, continuously stirring for 30min after dropwise adding, then stirring for reacting for 5h under the condition of N 2 atmosphere and 100 ℃ oil bath, naturally cooling to room temperature after the reaction is finished, centrifugally washing to be neutral by deionized water, centrifugally washing for 2-3 times by absolute ethyl alcohol, vacuum drying for 12-h at 60 ℃, then immersing the dried sample into 0.1-0.5 mol/L NaOH dilute solution, uniformly stirring, etching for 5-10 min at room temperature, washing to be neutral by deionized water after suction filtration, and vacuum drying for 12 h at 60 ℃ to obtain a RuCo-LDH/Ti 3 C 2 T x precursor; S4, respectively placing RuCo-LDH/Ti 3 C 2 T x precursors obtained in NaH 2 PO 2 ·H 2 O and S3 in an upstream phosphorus production area and a downstream reaction area of a tubular furnace according to a mass ratio of 1 (0.8-1.2), wherein the NaH 2 PO 2 ·H 2 O is paved to be 1-2 mm, the precursor paving thickness is controlled to be 0.5-1 mm, the distance between the two areas is kept to be 3-5 cm, introducing hydrogen-argon mixed gas (H 2 volume fraction 5%, ar is balance gas) into the tubular furnace, controlling the gas flow rate to be 50-80 mL/min, firstly introducing 30min to remove air in the furnace, heating to 300-400 ℃ at a heating rate of 2 ℃ per minute –1 , preserving heat for 2-3H, continuously maintaining the hydrogen-argon mixed gas flow in the heat preservation process, after the reaction is finished, naturally cooling to room temperature, and then stopping introducing air, and taking out a product to obtain the ruthenium-cobalt nitride-Ru composite catalyst based on Ti 3 C 2 T x , namely/CoN-CoP/Ti 3 C 2 T x .
2. 2. The method for preparing a ruthenium-embedded cobalt nitride-cobalt phosphide composite catalyst according to claim 1, wherein the dosage ratio of Co (NO 3 ) 2 ·6H 2 O、RuCl 3 ·nH 2 O, urea and deionized water) in S1 is 0.2 mmol:0.01 mmol:2 mmol:10 mL.
3. 3. The method for preparing the ruthenium-embedded cobalt nitride-cobalt phosphide composite catalyst based on Ti 3 C 2 T x according to claim 1, wherein the volume ratio of the Ti 3 C 2 T x solution to the N-dimethyl pyrrolidone solution in S2 is 5 mL/15 mL.
4. 4. Use of a ruthenium-embedded cobalt nitride-cobalt phosphide composite catalyst prepared by the preparation method according to any one of claims 1-3 and based on Ti 3 C 2 T x , wherein the ruthenium-embedded cobalt nitride-cobalt phosphide composite catalyst based on Ti 3 C 2 T x is used for catalyzing ammonia borane hydrolysis and hydrogen desorption reaction.
5. 5. The method according to claim 4, wherein the Ti 3 C 2 T x -based cobalt nitride-cobalt phosphide composite catalyst is used for catalyzing the hydrolysis and hydrogen release reaction of ammonia borane, and influences of different Ru doping amounts, catalyst components and reaction temperatures on the hydrolysis and hydrogen release performance of ammonia borane are discussed, and the catalytic hydrogen release result shows that under the condition of 298K, the conversion frequency (TOF) of the hydrolysis and hydrogen release reaction of ammonia borane catalyzed by the Ru/CoN-CoP/Ti 3 C 2 T x catalyst can reach 589.7 mol H2 ·mol Ru –1 ·min –1 .
6. 6. The use according to claim 4, wherein the ruthenium-embedded cobalt nitride-cobalt phosphide composite catalyst based on Ti 3 C 2 T x is used for circularly catalyzing ammonia borane hydrolysis hydrogen release reaction, and 80% of the initial catalytic activity can be maintained after 5 hydrolysis hydrogen release reactions are carried out.

Description

Preparation method and application of Ti 3C2Tx -based ruthenium-embedded cobalt nitride-cobalt phosphide composite catalyst Technical Field The invention belongs to the technical field of catalysts, and particularly relates to a preparation method and application of a ruthenium-embedded cobalt nitride-cobalt phosphide composite catalyst based on Ti 3C2Tx. Background Among the catalyst systems heretofore, rh, pt, ru-based noble metals or alloys thereof are ideal high activity catalysts, but the expensive price and scarcity of these noble metals have limited their widespread use. Studies have shown that Transition Metal Phosphides (TMPs) and Transition Metal Nitrides (TMNs) are potential catalysts due to their high conductivity and noble metal-like properties, exhibiting excellent electron transport properties. However, they are slow to kinetic in catalytic reactions because of their lower efficiency of adsorption and dissociation of reactants and water, resulting in lower intrinsic catalytic activity. Studies show that the catalytic performance can be significantly improved by adjusting the electronic configuration of the catalyst or coupling other active components to construct a heterostructure. In addition, the chemical composition is adjusted by doping external elements, so that a synergistic effect is generated, and the catalytic performance can be further improved. In addition to component regulation, regulation of microstructure is also a common strategy for improving the catalytic activity and stability of catalysts. In general, the larger particle size of the metal nanoparticles results in reduced utilization of active centers, and the high surface energy thereof is highly susceptible to agglomeration during catalysis to some extent. Recent studies have shown that the use of support materials to support metal nanoparticles can effectively inhibit agglomeration of the active metal, and can additionally provide active sites. Since 2011, mxnes has been found to have excellent electrical conductivity, good structural stability, and abundant surface functionality, these excellent structural properties make mxnes potentially useful in electrocatalytic and energy storage applications. It was found that interfacial coupling between Ti 3C2Tx mxnes and other active components can effectively exert its synergistic effect, optimizing the electronic structure to promote adsorption and desorption of intermediates, thereby kinetically promoting water dissociation. Although Ti 3C2Tx provides ideal load carriers for active components such as TMPs, TMNs and the like, and a composite system of the two has certain potential in the field of electrocatalysis, aiming at the ammonia borane hydrolysis hydrogen desorption reaction scene, the conventional Ti 3C2Tx -based TMPs/TMNs composite catalyst still has a plurality of short plates, so that the actual application requirements are difficult to meet, and the high-efficiency substitution of noble metal catalysts cannot be realized. Most of the existing systems are composed of single TMPs or TMNs components and Ti 3C2Tx, lack of cooperative construction of multiple active components, and further do not realize accurate regulation and control of noble metal doping, and the differences between catalytic activity and noble metal catalysts are still remained, wherein the electronic configuration cannot be optimized and the reaction energy barrier cannot be reduced through multi-component cooperation. In addition, the existing preparation method is easy to cause aggregation growth and poor dispersibility of active components on the surface of Ti 3C2Tx, and has weak interfacial bonding force, and in the ammonia borane hydrolysis hydrogen release cyclic reaction, the active components are easy to fall off and agglomerate, so that the cyclic stability and repeatability of the catalyst are attenuated, and the catalyst cannot adapt to long-term reaction working conditions. Meanwhile, the regulation and control of the composite system in the prior art are limited to single dimension, or only optimize the component proportion, or only simply load on the surface of a carrier, so that multiple targets of the improvement of the number of active sites, the enhancement of the intrinsic catalytic activity, the acceleration of reaction kinetics and the optimization of the circulation stability can not be realized. The defects become a core bottleneck for restricting the large-scale application of the Ti 3C2Tx -based TMPs/TMNs composite catalyst in the hydrolysis and hydrogen release reaction of ammonia borane. Disclosure of Invention Aiming at the defects of the prior art, the invention provides a preparation method and application of a Ti 3C2Tx -based ruthenium-embedded cobalt nitride-cobalt phosphide composite catalyst, and the Ru/CoN-CoP/Ti 3C2Tx prepared by the method is used for catalyzing ammonia borane hydrolysis hydrogen release reaction, and has good stability and repeatability. In or