Ternary nanometer catalyst used for hydrolyzing ammonia borane to release hydrogen and preparation method of ternary nanometer catalyst

Abstract

The invention provides a ternary nanometer catalyst used for hydrolyzing ammonia borane to release hydrogen and a preparation method of the ternary nanometer catalyst. The catalyst takes a metal-organic framework material of MIL-101 as a carrier and sodium borohydride as a reducing agent, and the multiple catalyst of RuCuCo@MIL-101 is obtained by reducing precursors of ruthenium salts, copper salts and cobalt salts. The specific surface area of the multiple catalyst synthesized with the preparation method reaches up to 2868m<2> / g, the grain size is around 6.9nm, good catalytic activity is exerted by catalyzing the ammonia borane to be hydrolyzed to release the hydrogen under the room temperature, transformation frequency (TOF) is 241.2mol H2 min<1> (mol Ru)<1>, and activation energy (Ea) is 48 kJ mol<1>. The catalyst is still good in stability after circulation tests are performed for 5 times; the ternary nanometer catalyst doped with non-noble metal has the advantages of even distribution of the metal particles, large specific surface area, more in catalytic active sites and the like, and compared with a conventional noble-metal catalyst, the ternary nanometer catalyst is low in cost, simple in preparation, easy to obtain raw materials, suitable for industrial production and good in application prospect.

Description

technical field [0001] The invention belongs to the field of hydrogen storage materials, and relates to a trimetal-loaded catalyst for efficiently catalyzing ammonia borane water to decompose hydrogen and a preparation method thereof. Background technique [0002] With the global environmental deterioration and energy crisis, there is an urgent need for a clean, efficient and renewable energy to replace fossil energy. Among many new energy sources, hydrogen energy is an ideal energy source. Among the many hydrogen storage materials that have come out, ammonia borane (NH 3 BH 3 , AB) is a hydrogen storage material with great application potential. The hydrogen content of ammonia borane is as high as 19.6 wt.%. It is non-toxic, stable at room temperature, and environmentally friendly. In the absence of a catalyst, it does not hydrolyze and release hydrogen at room temperature. Therefore, the preparation of catalysts with excellent performance is the core technology for wh...

AI Technical Summary

Problems solved by technology

For non-supported catalysts, it is easy to make the active component particles larger, prone to sintering and aggregation, and the mechanical strength is low. However, MOFs are used as the carrier to support metals. It is uniformly embedded inside and outside, and evenly dispersed. Therefore, it is of great significance to develop a low-cost and high-activity supported catalyst for catalyzing ammonia borane water to explain hydrogen.

[0003] Chinese patent "A Preparation Method of Binary Transition Metal Catalyst Catalyzing Hydrolysis of Ammoniaborane Patent No. 201110339872, Application Date 2011.11.1" uses in-situ synthesis method to synthesize binary transition metal FeCo alloy as catalyst for hydrogen production from ammonia borane The catalyst has high catalytic activity and low reaction activation energy. However, due to the magnetic properties of the metal nanoparticles FeCo in this invention, they are easy to aggregate with each other, resulting in easy reduction in catalytic performance and poor recycling performance.

[0004] Chinese patent application "Cu@mSiO for hydrogen production by hydrolysis of ammonia borane and hydrazine borane 2 Core-shell nanocatalyst and its preparation method, application number 201410186441.5, application date 2014.05.06", prepared in one pot by reverse micellar method, the core-shell nanostructure is composed of non-noble metal Cu, and the shell is composed of mesoporous silica mSiO2. Catalysts that catalyze ammonia borane and hydrazine borane to produce hydrogen have better catalytic effects, but the metal described in this invention is a single transition metal Cu, and the loading capacity is not high, and mesoporous SiO 2 As the shell, the catalytic active sites are reduced, resulting in a decrease in catalytic activity and catalyst life

Since the core-shell structure Ag@CoNi catalyst is not dispersed with a carrier or surfactant, the metal particles are easy to aggregate with each other, which easily reduces its catalytic performance and leads to poor recycling performance, which limits its application in actual production.

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