Transition metal single-atom catalyst as well as preparation method and application thereof

Abstract

The invention provides a transition metal single-atom catalyst. In the catalyst, transition metal single atoms are taken as active ingredients, carbon black is taken as a carrier, the loading capacityof the transition metal single atoms is 0.5-6wt%, and the highest loading capacity of the transition metal single atoms is higher than that of the prior art by 2-3 times. Various low-price transitionmetal single-atom catalysts with high dispersibility and high loading capacity are formed by inducing a limit range and by taking phenanthroline with strong complexation effect as a ligand and takingthe carbon black with high conductivity and high surface activity as the carrier. A preparation method of the transition metal single-atom catalyst has universality and can be used for preparing various low-price transition metal single-atom catalysts; according to the method, a Cr single-atom catalyst, an Nb single-atom catalyst, an Rh single-atom catalyst, a Cd single-atom catalyst, an Os single-atom catalyst and an Ir single-atom catalyst are prepared for the first time. Additionally, the preparation method has the advantages of being low in cost and simple in process and achieving large-scale production. Next, the catalyst has higher selectivity and Faraday efficiency in application of preparation of carbon monoxide by reducing carbon dioxide through electro-catalysis.

Description

technical field [0001] The invention relates to the technical field of preparation of micro-nano materials. More specifically, it relates to a universal transition metal single-atom catalyst and its preparation method and application. Background technique [0002] Homogeneous catalysts and heterogeneous catalysts have been widely used in the chemical industry as two types of catalysts, and they have their own characteristics and advantages. Homogeneous catalysts have the advantages of uniform active sites, high atom utilization, and easy adjustment of active sites, but they have poor stability and are difficult to separate from reactants. Heterogeneous catalysts have high stability and are easy to separate from the reactants, but their atom utilization is low, and only the atoms on the surface can contact the reactants to participate in the catalytic reaction. How to combine the advantages of the two types of catalysts is a hot spot and difficult problem in catalytic resea...

AI Technical Summary

Problems solved by technology

However, the method of impregnation and calcination of metal ions and supports still has problems such as complex synthesis methods and inability to prepare on a large scale.

And with MOFs or C 3 N 4 Such as the carrier needs to be calcined at a very high temperature to be carbonized, and the thermal movement of atoms is intensified at high temperature, which makes the metal easy to agglomerate and the metal loading cannot be increased.

Moreover, some current single-atom catalyst synthesis methods are not widely applicable, and it is impossible to synthesize a variety of single-atom catalysts with one method, so it is impossible to compare the role played by the central metal atom in the catalytic activity.

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