阅读说明：本技术 利用催化剂高效合成反钙钛矿材料的方法和应用 (Method for efficiently synthesizing anti-perovskite material by using catalyst and application ) 是由 邓永红 韩兵 冯东宇 张震 池上森 王庆容 于 2019-10-14 设计创作，主要内容包括：本发明涉及反钙钛矿材料的合成技术领域,具体涉及一种利用催化剂高效合成反钙钛矿材料的方法和应用。所述方法包括以下步骤：按照目标产物的化学计量比,将氢氧化锂和LiX进行混料机械磨碎处理,得到含锂的混合物料；或者按照目标产物的化学计量比,将氢氧化钠和NaX进行混料机械磨碎处理,得到含钠的混合物料,其中,X表示Cl、Br、I中的任一种；将所述含锂的混合物料或者含钠的混合物料置于催化剂层上,并在缺氧条件下(330～360)℃煅烧,得到反钙钛矿材料。本发明的方法可以极大的提高反钙钛矿材料的合成效率以及合成纯度,降低合成的时间成本同时还能节省能耗。(The invention relates to the technical field of synthesis of anti-perovskite materials, in particular to a method for efficiently synthesizing an anti-perovskite material by using a catalyst and application of the method. The method comprises the following steps: according to the stoichiometric ratio of a target product, carrying out mixing mechanical grinding treatment on lithium hydroxide and LiX to obtain a lithium-containing mixed material; or according to the stoichiometric ratio of a target product, carrying out mixing mechanical grinding treatment on sodium hydroxide and NaX to obtain a sodium-containing mixed material, wherein X represents any one of Cl, Br and I; and placing the lithium-containing mixed material or the sodium-containing mixed material on a catalyst layer, and calcining at 330-360 ℃ under an anoxic condition to obtain the anti-perovskite material. The method can greatly improve the synthesis efficiency and the synthesis purity of the anti-perovskite material, reduce the synthesis time cost and save the energy consumption.)

1. A method for efficiently synthesizing an anti-perovskite material by using a catalyst is characterized by comprising the following steps:

according to the stoichiometric ratio of a target product, carrying out mixing mechanical grinding treatment on lithium hydroxide and LiX to obtain a lithium-containing mixed material; or according to the stoichiometric ratio of a target product, carrying out mixing mechanical grinding treatment on sodium hydroxide and NaX to obtain a sodium-containing mixed material, wherein X represents any one of Cl, Br and I;

and placing the lithium-containing mixed material or the sodium-containing mixed material on a catalyst layer, and calcining at 330-360 ℃ under an anoxic condition to obtain the anti-perovskite material.

2. The method for efficiently synthesizing an anti-perovskite material using a catalyst according to claim 1, wherein the material of the catalyst layer is at least one of an oxide of a transition metal and a sulfide of a transition metal.

3. The method for efficiently synthesizing an anti-perovskite material by using the catalyst according to claim 2, wherein the oxide of the transition metal is at least one of copper oxide, nickel oxide, ferroferric oxide, cobalt oxide, manganese oxide, and ruthenium oxide; the sulfide of the transition metal is at least one of copper sulfide and ferrous sulfide.

4. The method for efficiently synthesizing an anti-perovskite material by using the catalyst according to claim 1, wherein the calcination time is (30 to 60) min.

5. The method for efficiently synthesizing an anti-perovskite material using a catalyst as claimed in claim 1, wherein the anti-perovskite obtained has a general formula of Li_3-x-δM_x/2O(X_1-zX′_z)_1-δ(ii) a Or Li_3-x-δM_x/3O(X_1-zX′_z)_1-δWherein x is more than or equal to 0 and less than or equal to 1, delta is more than or equal to 0 and less than or equal to 0.2, and z is more than or equal to 0 and less than or equal to 1; m is selected from one or more of Ca, Mg and Al; x, X' each represents halogen;

or alternatively, Na_3-y-θM_y/2O(X_1-τX′_τ)_1-θOr Na_3-y-θM_y/3O(X_1-τX′_τ)_1-θWherein y is more than or equal to 0 and less than or equal to 0.2, theta is more than or equal to 0 and less than or equal to 1, and tau is more than or equal to 0 and less than or equal to 1; m is selected from one or more of Ca, Mg and Al; x, X' all represent halogens.

6. The method for efficiently synthesizing an anti-perovskite material using a catalyst as claimed in claim 1, further comprising adding a halide of an alkaline earth metal to the lithium-containing mixed material or the sodium-containing mixed material and performing a mixing treatment.

7. The method for efficient synthesis of an anti-perovskite material using a catalyst as claimed in claim 1, wherein the anti-perovskite material is Li₃OCl、Li₃OCl_0.5Br_0.5、Li₃OCl_0.8Br_0.2、Na₃Any of OBr.

8. The method for efficiently synthesizing an anti-perovskite material by using a catalyst according to claim 5, wherein the obtained anti-perovskite further comprises (0-10) wt% of a catalyst and derivatives thereof; the derivative of the catalyst comprises a metal simple substance obtained by reduction of the catalyst and a compound obtained by chemical combination reaction of the catalyst.

9. A lithium metal battery comprises a solid electrolyte, and is characterized in that the solid electrolyte comprises the anti-perovskite material prepared by the method for efficiently synthesizing the anti-perovskite material by using the catalyst according to any one of claims 1 to 8, and the anti-perovskite material is a lithium-containing anti-perovskite material.

10. A sodium metal battery, which comprises a solid electrolyte, and is characterized in that the solid electrolyte comprises the anti-perovskite material prepared by the method for efficiently synthesizing the anti-perovskite material by using the catalyst according to any one of claims 1 to 8, and the anti-perovskite material is a sodium-containing anti-perovskite material.

Technical Field

The invention belongs to the technical field of synthesis of anti-perovskite materials, and particularly relates to a method for efficiently synthesizing an anti-perovskite material by using a catalyst and application of the method.

Background

Lithium/sodium metal batteries are currently considered as potential candidates for next-generation energy storage devices, and battery systems represented by lithium air batteries and lithium sulfur batteries are receiving wide attention. However, the safety problems of the conventional lithium ion battery which is widely used at present are increasingly highlighted, and the main root of the problems is that the liquid electrolyte adopted by the conventional lithium ion battery has flammable and explosive properties. Based on the above two points, the all-solid-state lithium/sodium metal battery using the solid electrolyte becomes the focus of the next generation of metal negative electrode battery research.

For example, the anti-perovskite material has high working voltage, does not generate side reaction with the negative electrode, has high ionic conductivity at normal temperature, low synthesis cost, convenient transportation and the like, and can be used as an inorganic solid electrolyte material in a lithium/sodium metal negative electrode battery. Compared with other inorganic solid electrolytes, the material has the outstanding advantage of extremely high ionic conductivity at normal temperature (lithium-rich anti-perovskite material Li₃OCl for example, the lithium ion conductivity at 25 ℃ is 0.85X 10^-3S/cm). The battery system adopting the solid electrolyte can realize the advantages of higher-rate charge and discharge performance, high efficiency, long cycle life and the like. However, the synthesis of anti-perovskite materials tends to be difficult to achieve with satisfactory purity, because of the high energy barrier present in the synthesis reaction resulting in the presence of a large number of intermediates in the final product. In order to overcome the difficulty, the actual operation needs to further adjust the reaction conditions, such as adding a vacuum reaction environment, prolonging the high-temperature reaction time (more than 24h) and the like,these add significant cost to the synthesis of materials and time, further limiting the widespread use of anti-perovskite materials.

Disclosure of Invention

Aiming at the problems of low product purity, long reaction time and the like caused by high reaction energy barrier in the synthesis process of the anti-perovskite material at present, the invention provides a method for efficiently synthesizing the anti-perovskite material by using a catalyst.

Further, the invention also provides a lithium metal battery and a sodium metal battery containing the anti-perovskite material obtained by the method.

In order to achieve the purpose, the technical scheme of the invention is as follows:

a method for efficiently synthesizing an anti-perovskite material by using a catalyst comprises the following steps:

according to the stoichiometric ratio of a target product, carrying out mixing mechanical grinding treatment on lithium hydroxide and LiX to obtain a lithium-containing mixed material; or according to the stoichiometric ratio of a target product, carrying out mixing mechanical grinding treatment on sodium hydroxide and NaX to obtain a sodium-containing mixed material, wherein X represents any one of Cl, Br and I;

and placing the lithium-containing mixed material or the sodium-containing mixed material on a catalyst layer, and calcining at 330-360 ℃ under an anoxic condition to obtain the anti-perovskite material.

Correspondingly, the lithium metal battery comprises a solid electrolyte, wherein the solid electrolyte comprises the anti-perovskite material prepared by the method for efficiently synthesizing the anti-perovskite material by using the catalyst, and the anti-perovskite material is a lithium-containing anti-perovskite material.

Further, the lithium metal battery comprises a solid electrolyte, wherein the solid electrolyte comprises the anti-perovskite material prepared by the method for efficiently synthesizing the anti-perovskite material by using the catalyst, and the anti-perovskite material is a lithium-containing anti-perovskite material.

The invention has the technical effects that:

compared with the prior art, the method for efficiently synthesizing the anti-perovskite material by using the catalyst can synthesize the anti-perovskite material with the purity of 98% or more at 330-360 ℃ within 1 hour of calcination time by using the catalyst, and the reaction energy barrier is reduced by using the catalyst, so that the synthesis efficiency and the synthesis purity of the anti-perovskite material are greatly improved, the synthesis time cost is reduced, and the energy consumption is reduced.

The lithium metal battery and the sodium metal battery have the characteristic of high purity because the active substance of the anode is synthesized by the synthesis method, so that the content of the active material of the battery can be improved, and the influence of impurities on the electrochemical performance of the battery can be reduced.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to these drawings without creative efforts.

FIG. 1 shows the anti-perovskite material Li prepared in example 1₃XRD pattern of OCl;

FIG. 2 shows the anti-perovskite material Li prepared in example 1₃SEM image of OCl;

FIG. 3 shows the anti-perovskite material Li prepared in example 2₃OCl_0.5Br_0.5XRD pattern of (a);

FIG. 4 shows the anti-perovskite material Li prepared in example 2₃OCl_0.5Br_0.5SEM picture of (1);

FIG. 5 shows the anti-perovskite material Li prepared in example 2₃OCl_0.5Br_0.5SEM image at a further magnification;

FIG. 6 shows the anti-perovskite material Li prepared in example 3₃OCl_0.5Br_0.5XRD pattern of (a);

FIG. 7 shows the anti-perovskite material Li prepared in example 4₃XRD pattern of OCl;

FIG. 8 is a schematic view of an embodimentExample 5 preparation of the resulting anti-perovskite Material Li₃OCl_0.8Br_0.2XRD pattern of (a);

FIG. 9 shows the perovskite-resistant material Na prepared in example 6₃SEM image of OBr;

FIG. 10 is an XRD pattern of an anti-perovskite material prepared according to a comparative example of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

The invention provides a method for efficiently synthesizing an anti-perovskite material by using a catalyst, which comprises the following steps:

according to the stoichiometric ratio of a target product, carrying out mixing mechanical grinding treatment on lithium hydroxide and LiX to obtain a lithium-containing mixed material; or according to the stoichiometric ratio of a target product, carrying out mixing mechanical grinding treatment on sodium hydroxide and NaX to obtain a sodium-containing mixed material, wherein X represents any one of Cl, Br and I;

and placing the lithium-containing mixed material or the sodium-containing mixed material on a catalyst layer, and calcining at 330-360 ℃ under an anoxic condition to obtain the anti-perovskite material.

The technical solution of the present invention is explained in further detail below.

When the raw materials are mixed and mechanically crushed, alkaline earth metal halide can be added, and the obtained anti-perovskite with the general formula of Li is added_3-x-δM_x/2O(X_1-zX′_z)_1-δ(ii) a Or Li_3-x-δM_x/3O(X_1-zX′_z)_1-δWherein x is more than or equal to 0 and less than or equal to 1, delta is more than or equal to 0 and less than or equal to 0.2, and z is more than or equal to 0 and less than or equal to 1; m is selected from one or more of Ca, Mg and Al; x, X' each represents halogen; or the obtained anti-perovskite has the general formula Na_3-y-θM_y/2O(X_1-τX′_τ)_1-θOr Na_3-y-θM_y/3O(X_1-τX′_τ)_1-θWherein y is more than or equal to 0 and less than or equal to 0.2, theta is more than or equal to 0 and less than or equal to 1, and tau is more than or equal to 0 and less than or equal to 1; m is selected from one or more of Ca, Mg and Al; x, X' all represent halogens. The mechanical crushing can be ball milling treatment by a ball mill and other mechanical grinding modes which can enable raw materials to be uniformly mixed.

The obtained lithium-containing mixed material or sodium-containing mixed material is placed on a catalyst layer, and catalysis can be realized by means of the catalyst layer. The catalyst is made into a material layer, so that the problem that the catalyst is mixed with a product and is difficult to separate in the reaction process is avoided. The material of the catalyst layer may be at least one of an oxide of a transition metal and a sulfide of a transition metal.

For example, the transition metal oxide can be at least one of copper oxide, nickel oxide, ferroferric oxide and cobalt oxide; the sulfide of the transition metal is at least one of copper sulfide and ferrous sulfide.

In particular, the catalyst may be deposited on the surface of the support vessel, for example, the catalyst may be deposited on the surface of a crucible, thereby forming a catalyst layer.

In the calcining process, the anoxic condition can effectively avoid the occurrence of side reactions. The oxygen deficiency can be realized by vacuumizing, and protective atmosphere such as nitrogen, argon, helium and the like can also be introduced.

The moisture content in the reaction system during calcination cannot exceed 1 wt%, and if it exceeds 1 wt%, side reactions occur, resulting in increased product impurities.

And (3) keeping the temperature for 30-60 min at the calcining temperature to obtain the anti-perovskite material.

The mechanism of the chemical reaction that occurs during the above calcination is as follows:

anion doping mechanism: 2LiOH + (1-z) LiA' + z LiA ═ Li₃OA’_1–zA_z+H₂O；

The mechanism of cation doping: 2LiOH + (x/2) MA₂+(1-x)LiA＝Li_3-xM_x/2OA+H₂O；

The mechanism of anion and cation deletion is as follows: (1-. delta.) LiA +2LiOH ═ Li_3-δOA_1-δ+H₂O；

Under the reaction mechanism, the lithium-containing anti-perovskite structural general formula Li is obtained_3-x-δM_x/2O(A_1-zA′_z)_1-δ. The cation is alkaline earth metal ion, specifically Ca, Mg, Al, and when the cation is trivalent cation, its structural formula needs to be changed into Li_3-x-δM_x/3O(A_1-zA′_z)_1-δ. Accordingly, the same mechanism exists for sodium-containing anti-perovskite materials and is not repeated here.

Due to OH in lithium hydroxide in the reaction process^-The bond energy of hydrogen and oxygen is high and difficult to break, which is directly reflected by the difficulty of moving the reaction to the right, and if some external measures are not taken, a great amount of intermediate phase containing hydroxide radical aggregation, such as Li, exists in the finally obtained product₂(OH) Cl, etc. and results in difficulty in obtaining high purity anti-perovskite materials. The catalyst plays a role in efficiently catalyzing OH in the anti-perovskite synthesis reaction^-The middle hydrogen-oxygen bond is broken, so that the whole reaction balance is moved rightwards, and the target product with high purity is finally obtained.

In the above preparation method, the catalyst inevitably reacts, so that the obtained anti-perovskite material is also doped with a small amount of catalyst and catalyst derivatives, and the content of the catalyst and the catalyst derivatives in the anti-perovskite material is (0 to 10) wt%. The derivative of the catalyst can be a metal simple substance obtained by the reduction of the catalyst and a compound obtained by the combination reaction of the catalyst. Such as copper, nickel, iron, cobalt, manganese, ruthenium metals, and compounds corresponding to the listed metals, and the like.

The anti-perovskite obtained by the method can be used as a solid electrolyte of a lithium metal battery or a solid electrolyte of a sodium metal battery, wherein the solid electrolyte of the lithium metal battery is a lithium-containing anti-perovskite material, and the solid electrolyte of the sodium metal battery is a sodium-containing anti-perovskite material.

To more effectively explain the technical solution of the present invention, the following description is made by way of examples.