CN110429284B

CN110429284B - High-capacity and high-rate flexible zinc ion battery and application thereof

Info

Publication number: CN110429284B
Application number: CN201910585737.7A
Authority: CN
Inventors: 卢锡洪; 曾银香; 王静
Original assignee: National Sun Yat Sen University
Current assignee: National Sun Yat Sen University
Priority date: 2019-07-01
Filing date: 2019-07-01
Publication date: 2020-11-10
Anticipated expiration: 2039-07-01
Also published as: CN110429284A

Abstract

The invention provides a flexible zinc ion battery with high capacity and high multiplying power and application thereof. The positive electrode of the flexible zinc ion battery is P-MoO_3‑x@Al₂O₃The nano-rod, the cathode are Zn nano-materials, the electrolyte is zinc chloride solution, and the anode material and the cathode material are synthesized on the flexible carbon fiber carrier. The anode material and the cathode material of the zinc ion battery are synthesized on the carbon fiber substrate, so that the specific surface area of the electrode material is increased, the flexibility and the capacity performance of the zinc ion battery are effectively improved, and the anode material of the zinc ion battery is prepared on MoO₃The surface of the electrode is coated with a layer of conductive Al with proper thickness₂O₃The nano material can prevent the structural collapse of the electrode material in the charging and discharging process, greatly improve the cycle stability of the electrode material, realize surface phosphate modification and oxygen vacancy regulation and control of the battery, increase the electrode conductivity and active sites, obtain an anode material with excellent performance and improve the specific capacity of the battery.

Description

High-capacity and high-rate flexible zinc ion battery and application thereof

Technical Field

The invention relates to the technical field of electrochemical energy storage batteries, in particular to a high-capacity high-rate flexible zinc ion battery and application thereof.

Background

The development of various novel energy sources and the realization of the efficient conversion and utilization of new energy sources by utilizing different types of energy storage devices are the key points of energy research at present, and zinc ion batteries gradually attract the attention of researchers in various energy storage devices. The zinc metal has abundant resources, low cost, low toxicity, low equilibrium potential, high hydrogen overpotential, good stability in water, and high energy density (819mAh g)^-1) And the like. The zinc ion battery is a high-efficiency and practical energy storage device, has low cost, high energy density, safety, no toxicity and environment friendlinessGood and the like. At present, zinc ion batteries are widely applied to various fields of society, such as emergency power supplies, rail transit, national defense communication equipment, household appliances, electronic storage equipment, electric vehicles and the like. However, due to the high energy density of metallic zinc, its performance is mainly limited by the positive electrode material. Up to now, MnO₂、V₂O₅The Prussian blue and the like are main anode materials of the zinc ion battery, and the three anode materials of the zinc ion battery are researched more mature at present and have wide application. However, the positive electrode material of the current zinc ion battery has several problems to be solved: 1. the actual specific capacity value is not high, so that the performance of the zinc ion battery is limited; 2. most of zinc-based battery anode materials have poor conductivity, so that the capacity of the zinc-based battery anode materials is greatly lost in the rapid charge and discharge process; 3. the zinc ion battery can undergo irreversible phase change in the cyclic charge and discharge process, so that the cycle life of the battery is poor, and the irreversible phase change is also an important reason for limiting the further popularization of the zinc ion battery; 4. at present, most substrates and devices are inflexible, and the application of zinc-based batteries in wearable equipment and light and thin equipment is limited. The prior art CN108400392A discloses a rechargeable flexible zinc ion battery, which uses a conductive polymer/cellulose paper/graphite nanosheet as a positive electrode and a galvanized conductive carbon material as a negative electrode to obtain the flexible zinc ion battery, but the zinc ion battery has no relevant improvement on the capacity and rate capability of the battery, and the problem of the zinc ion battery is not completely solved.

Therefore, it is desirable to develop a high capacity, long life, flexible rechargeable zinc ion battery.

Disclosure of Invention

The invention aims to overcome the defects and shortcomings of low specific capacity value, poor conductivity, short service life and the like of the conventional zinc ion battery and provide a flexible zinc ion battery with high capacity and high multiplying power.

The invention aims to provide an application of a high-capacity and high-rate flexible zinc ion battery in energy storage.

The above purpose of the invention is realized by the following technical scheme:

the positive electrode of the zinc ion battery is P-MoO_3-x@Al₂O₃The nano-rod, the cathode are Zn nano-materials, the electrolyte is zinc chloride solution, and the anode material and the cathode material are synthesized on the flexible carbon fiber carrier.

The zinc ion battery of the invention adopts P-MoO_3-x@Al₂O₃The nano-rod is a positive electrode material, MoO₃Coating a layer of Al on the material₂O₃Protective film to obtain MoO₃@Al₂O₃Material, to MoO₃@Al₂O₃Carrying out phosphate radical modification and oxygen vacancy regulation to obtain P-MoO_3-x@Al₂O₃Nano rod, adding MoO₃The conductivity and the active site of the zinc-ion battery lead the capacity of the assembled zinc-ion battery to be greatly improved, and Al₂O₃The protective film prevents the structure collapse in the charging and discharging process, and greatly improves the circulating stability of the protective film.

Synthesizing positive electrode P-MoO on flexible carbon fiber carrier_3-x@Al₂O₃The nanorod and the negative electrode Zn nanomaterial not only increase the specific surface area of the electrode material, but also effectively improve the flexibility and the capacity performance of the zinc ion battery, so that the nanorod and the negative electrode Zn nanomaterial can be suitable for assembling the flexible zinc ion battery with small volume.

Preferably, the P-MoO_3-x@Al₂O₃The nano-rod comprises a flexible carbon fiber substrate and MoO grown on the flexible carbon fiber substrate₃Nanorods, said MoO₃The nano-rods are wrapped with an alumina layer, and the P exists in P-MoO_3-x@Al₂O₃The surface layer of the nano rod.

Preferably, the MoO₃The diameter of the nano rod is 150-300 nm. MoO of the invention₃The nano-rods have uniform particle size.

Preferably, the thickness of the aluminum oxide layer is 10-30 nm. By in MoO₃The surface is coated with a layer of high-conductivity alumina with proper thickness and stable performance, thereby leading the MoO₃@Al₂O₃The stability of the positive electrode is improvedAnd (5) rising.

Preferably, the P-MoO_3-x@Al₂O₃The preparation method of the nano-rod comprises the following steps: firstly, MoO is prepared on a substrate by a hydrothermal method₃Nanorods followed by a MoO₃Depositing alumina on the nano-rod to obtain MoO₃@Al₂O₃Nitrogen gas is used as carrier gas, and 0.1-1.0 g NaH is used₂PO₂·H₂O is used as a P source, and the P-MoO is obtained by annealing at the high temperature of 300-500 ℃ for 1-2 hours_3-x@Al₂O₃And (4) nanorods.

Preferably, the MoO₃@Al₂O₃In N₂In an atmosphere, 0.5g of NaH₂PO₂·H₂O is used as a P source, and P-MoO is obtained by annealing at the high temperature of 400 ℃ for 1 hour_3-x@Al₂O₃。

Co-heating with a suitable phosphorus source in a suitable atmosphere, and annealing at a certain temperature to finally obtain the P-MoO with excellent electrochemical performance_3-x@Al₂O₃An electrode material.

Preferably, the hydrothermal reaction temperature is 120-160 ℃ and the time is 5-30 min. By regulating and controlling the temperature and time of hydrothermal reaction, a layer of MoO with uniform particle size distribution grows on the flexible carbon fiber substrate₃Nano-rod

Preferably, the aluminum oxide is deposited by an atomic layer deposition technology, the precursor is trimethylaluminum and water, the temperature is 10-200 ℃, and the coating thickness is 50-200 cycles. The thickness of the deposited aluminum oxide layer can be reasonably controlled by controlling the ALD temperature, and further the conductive stability of the anode material is improved.

Preferably, the temperature is 10-200 ℃, and the coating thickness is 100 cycles.

Wherein the MoO₃The preparation method of the nano-rod comprises the following steps:

s1, dissolving 2-3 g of zinc molybdate in 20mL of deionized water, adding 3-6 mL of concentrated hydrochloric acid (12M) as a seed solution, soaking carbon fibers in the solution for 5-10 min, then drying in a heating plate at 250-400 ℃, repeatedly soaking and drying for three times to obtain MoO₃A seed layer,

s2, dissolving 0.5g of ammonium molybdate in 17mL of deionized water, adding 3mL of concentrated nitric acid (16M) as a hydrothermal solution, and growing MoO in the solution₃Performing hydrothermal reaction on carbon fibers of the precursor at the temperature of 140 ℃ for 5-30min, and drying after hydrothermal reaction to obtain MoO₃And (4) nanorods.

Preferably, the Zn nano material is prepared by a constant current electrodeposition method, the electrolyte is a mixed aqueous solution of 125g/L zinc sulfate, 125g/L sodium sulfate and 20g/L boric acid, and the deposition current is 30-60 mA cm^-2The deposition time is 5-15 min.

An application of a flexible zinc ion battery in energy storage.

Compared with the prior art, the invention has the beneficial effects that:

(1) the positive electrode of the zinc ion battery of the invention is P-MoO_3-x@Al₂O₃The nano rod and the negative electrode Zn nano material are synthesized on the carbon fiber substrate, so that the specific surface area of the electrode material is increased, and the flexibility and the capacity performance of the zinc ion battery are effectively improved, so that the method is suitable for assembling the flexible zinc ion battery with small volume.

(2) The anode material of the zinc ion battery is in MoO₃The surface of the electrode is coated with a layer of conductive Al with proper thickness₂O₃Nanomaterial to prevent P-MoO_3-x@Al₂O₃The structure of the nano rod collapses in the charging and discharging processes, so that the cycling stability of the nano rod is greatly improved.

(3) The zinc ion battery realizes surface phosphate modification and oxygen vacancy regulation, increases electrode conductivity and active sites, and obtains P-MoO with excellent performance_3-x@Al₂O₃The specific capacity of the battery is improved by the positive electrode material.

Drawings

FIG. 1: (a) is MoO in example 1₃Scanning Electron Microscope (SEM) image of the electrode, wherein (b) is P-MoO in example 1_3-x@Al₂O₃SEM pictures of the electrodes.

FIG. 2: SEM picture of Zn negative electrode in example 1.

FIG. 3: in example 1P-MoO_3-x@Al₂O₃X-ray powder diffraction pattern of the electrode.

FIG. 4: P-MoO in example 1_3-x@Al₂O₃Electrodes (a) Mo 3d XPS and (b) P2P and Al 2P XPS.

FIG. 5: (a) the discharge curves of the zinc-ion batteries of example 1 and comparative examples 1-2 were obtained, and (b) the cycle life test curves of the zinc-ion batteries of example 1 and comparative examples 1-2 were obtained.

FIG. 6: capacity retention when the flexible zinc ion battery device is bent and a photograph thereof.

Detailed Description

The present invention will be further described with reference to specific embodiments, but the present invention is not limited to the examples in any way. The starting reagents employed in the examples of the present invention are, unless otherwise specified, those that are conventionally purchased.

Example 1

A flexible zinc ion battery with high capacity and high multiplying power has a positive electrode of P-MoO_3-x@Al₂O₃The nanorod is provided with a Zn nano material as a negative electrode, the electrolyte is 2M zinc chloride solution, and the thickness of the aluminum oxide layer is 20 nm. MoO₃The diameter of the nano rod is 200 nm.

P-MoO_3-x@Al₂O₃The preparation method of the nano-rod comprises the following steps:

preparation to obtain MoO₃And (3) nano-rods: using commercial carbon fiber (2cm multiplied by 3cm) subjected to ultrasonic treatment in absolute ethyl alcohol for 10 minutes as a flexible substrate, dissolving 2.5g of zinc molybdate in 20mL of deionized water, adding 5mL of concentrated hydrochloric acid (12M) as precursor liquid, soaking the carbon fiber in the solution for 10 minutes, then drying the carbon fiber in a heating plate at 340 ℃, repeatedly soaking and drying the carbon fiber for three times to obtain MoO₃A precursor;

0.5g ammonium molybdate is dissolved in 17mL deionized water, 3mL concentrated nitric acid is added as a hydrothermal solution, and MoO grows in the solution₃Performing hydrothermal reaction on carbon fibers of the precursor at the temperature of 140 ℃ for 5min, and drying after hydrothermal reaction to obtain MoO₃A nanomaterial;

preparation of MoO₃@Al₂O₃：Al₂O₃The layers are obtained by ALD atomic layer deposition with Trimethylaluminum (TMA) and water (H) as the precursors₂O), the temperature is 180 ℃, and the coating thickness is as follows: 100 cycles;

preparation of P-MoO_3-x@Al₂O₃And (3) nano-rods: nitrogen as carrier gas in a tube furnace with 0.5g NaH₂PO₂·H₂Annealing O as P source at 400 deg.C for 1 hr to obtain P-MoO_3-x@Al₂O₃And (3) nano materials.

The preparation method of the Zn anode material comprises the following steps:

the synthesis of Zn cathode material on the flexible carbon cloth is realized by a constant current electrodeposition method, commercial carbon fiber (1cm multiplied by 2cm) after being treated by ultrasonic for 10 minutes in absolute ethyl alcohol is taken as a flexible substrate, the electrodeposition solution of Zn comprises 125g/L zinc sulfate, 125g/L sodium sulfate and 20g/L boric acid aqueous solution, and the electrodeposition current density is 40mAcm^-2The time period was 5 minutes. The electrolyte of the battery is 2M ZnCl₂An aqueous solution.

And (3) performance testing:

for the prepared MoO₃And P-MoO_3-x@Al₂O₃The electrode was subjected to field emission scanning electron microscopy, and the results are shown in FIGS. 1 (a) and (b), which shows that a uniform layer of MoO was grown on the flexible carbon cloth fibers₃Nanorod array of Al deposition₂O₃The shape of the layer and the layer after the co-thermal reduction of the phosphorus source of the tube furnace has no obvious change.

Fig. 2 shows a scanning electron microscope image of Zn electrodeposition on flexible carbon fibers, from which it can be seen that the carbon fiber surface is coated with a layer of uniform nanosheets.

FIG. 3 adopts X-ray diffraction test, and the test result shows that the P-MoO obtained by the experiment_3-x@Al₂O₃The electrode has high crystallinity and contains MoO as main component₃。

FIG. 4 further illustrates P-MoO using X-ray photoelectron spectroscopy (XPS)_3-X@Al₂O₃The chemical composition and valence state of the surface of the sample show that P-MoO_3-X@Al₂O₃Three valence states of Mo in sample⁶⁺、Mo⁵⁺And Mo⁴⁺Coexistence is carried out. In addition, P2P XPS spectra indicate P-MoO_3-X@Al₂O₃P element exists on the surface of the sample, and P-MoO_3-X@Al₂O₃A clear Al 2p signal appeared in the sample, indicating Al₂O₃The plating was successful.

FIG. 5a uses a constant current charge and discharge test in an electrochemical method to study the respective MoO₃、MoO₃@Al₂O₃And P-MoO_3-X@Al₂O₃The energy storage performance of the zinc ion battery as the anode can be seen by discharge curves under different current densities, namely P-MoO_3-X@Al₂O₃The zinc ion battery as the positive electrode has more excellent capacity performance than other two batteries under all current densities, has a longer and higher discharge platform, and the specific capacity can reach 257.7mAh g^-1This indicates that the capacity of the battery is improved after the introduction of the low valence molybdenum and the surface phosphate ions. Furthermore, as can be seen from FIG. 5b, based on P-MoO_3-X@Al₂O₃The positive electrode of the zinc ion battery still has 69.2 percent of capacity retention rate after being continuously charged and discharged for 100 times, compared with MoO₃、MoO₃@Al₂O₃The cycle stability of the anode is greatly improved, which shows that the anode has excellent cycle stability.

FIG. 6 is a schematic representation of a process using P-MoO_3-X@Al₂O₃The photo of the flexible zinc ion battery device assembled by taking the Zn nano material as the cathode is taken as the anode, and the assembled zinc ion battery still keeps good performance under different bending states.

In conclusion, the zinc ion battery has the advantages of high capacity, high multiplying power, good flexibility and the like, and has a great application prospect in the aspect of energy storage.

Examples 2 to 8

The operation procedures of examples 2 to 8 were the same as those of example 1, except that MoO was hydrothermally synthesized₃Time of, heating temperature in tube furnace, quality of sodium hypophosphite and ALD deposition oxidationThe temperature of the aluminum and its plating thickness.

Specific hydrothermal synthesis of MoO₃The time of the ALD deposition, the heating temperature in the tube furnace, the quality of the sodium hypophosphite and the temperature of the ALD deposited alumina as well as the coating thickness thereof and the results of the examples are listed in table 1.

TABLE 1

Serial number	Hydrothermal time/min	Calcination temperature/. degree.C	NaH₂PO₂/g	Number of cycles of electrodeposition	Deposition temperature/. degree.C
						Example 2	10	300	0.5	100	180
Example 3	30	300	0.5	100	180
						Practice ofExample 4	5	300	0.2	100	180
Example 5	5	300	1	100	180
						Example 6	5	300	0.5	200	180
Example 7	5	300	0.5	100	100

Comparative examples 1 to 5

The operation procedures of comparative examples 1 to 5 are the same as those of example 1, except that MoO is hydrothermally synthesized₃Time of the ALD process, heating temperature in the tube furnace, mass of sodium hypophosphite and temperature of ALD deposited alumina and its plating thickness.

Specific hydrothermal synthesis of MoO₃Time of, heating temperature in tube furnace, quality of sodium hypophosphite and temperature of ALD deposited alumina and its plating film thickness and examplesThe results are shown in Table 2.

TABLE 2

Serial number	Hydrothermal time/min	Calcination temperature/. degree.C	NaH₂PO₂/g	Number of cycles of electrodeposition	Deposition temperature/. degree.C
						Comparative example 1	5	300	0	0	180
Comparative example 2	5	300	0.5	0	180
						Comparative example 3	5	300	0	100	180

Result detection

The specific capacity values, the stability and the multiplying power of the examples and the comparative examples are detected, and the related detection results are shown in table 3.

Wherein the stability is characterized by the capacity retention rate of the battery after the battery is continuously charged and discharged for 100 times.

TABLE 3

Serial number	Specific volume value	Capacity retention rate
			Example 2	209.3mAh g^-1	63.5％
Example 3	184.7mAh g^-1	57.8％
			Example 4	140.5mAh g^-1	67.5％
Example 5	121.3mAh g^-1	60.1％
			Example 6	218.4mAh g^-1	64.0％
Example 7	227.7mAh g^-1	55.3％
			Comparative example 1	115.8mAh g^-1	24.5％
Comparative example 2	258.6mAh g^-1	40.8％
			Comparative example 3	113.6mAh g^-1	61.4％

It should be understood that the above-described embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. The flexible zinc ion battery with high capacity and high multiplying power is characterized in that the positive electrode of the zinc ion battery is P-MoO_3-x@Al₂O₃The negative electrode of the nano rod is made of Zn nano materialThe electrolyte is zinc chloride solution, and the anode and the cathode are both synthesized on a flexible carbon fiber carrier.

2. The flexible zinc-ion battery of claim 1, wherein the P-MoO is_3-x@Al₂O₃The nano-rod comprises a flexible carbon fiber substrate and MoO grown on the flexible carbon fiber substrate₃Nanorods, said MoO₃The nano-rods are wrapped with an alumina layer, and the P exists in P-MoO_3-x@Al₂O₃The surface layer of the nano rod.

3. The flexible zinc-ion battery of claim 2, wherein the MoO₃The diameter of the nano rod is 150-300 nm.

4. The flexible zinc-ion battery of claim 2, wherein the aluminum oxide layer has a thickness of 10 to 30 nm.

5. The flexible zinc-ion battery of claim 2, wherein the P-MoO is_3-x@Al₂O₃The preparation method of the nano-rod comprises the following steps: firstly, MoO is prepared on a substrate by a hydrothermal method₃Nanorods followed by a MoO₃Depositing alumina on the nano-rod to obtain MoO₃@Al₂O₃Using inert gas as carrier gas, and 0.1-1.0 g NaH₂PO₂·H₂O is used as a P source, and the P-MoO is obtained by annealing at the high temperature of 300-500 ℃ for 1-2 hours_3-x@Al₂O₃And (4) nanorods.

6. The flexible zinc-ion battery of claim 5, wherein the MoO₃@Al₂O₃In N₂In an atmosphere, 0.5g of NaH₂PO₂·H₂O is used as a P source, and P-MoO is obtained by annealing at the high temperature of 400 ℃ for 1 hour_3-x@Al₂O₃。

7. The flexible zinc-ion battery of claim 5, wherein the hydrothermal reaction temperature is 120-160 ℃ and the time is 5-30 min.

8. The flexible zinc-ion battery of claim 5, wherein the aluminum oxide is deposited by an atomic layer deposition technique, the precursor is trimethylaluminum and water, the volume ratio of trimethylaluminum to water is 1:1, and the temperature is 10-200 ℃.

9. The flexible zinc ion battery of claim 1, wherein the Zn nano-material is prepared by a constant current electrodeposition method, the electrolyte is a mixed aqueous solution of 125g/L zinc sulfate, 125g/L sodium sulfate and 20g/L boric acid, and the deposition current is 30-60 mA cm^-2The deposition time is 5-15 min.

10. Use of a flexible zinc-ion battery according to any one of claims 1 to 9 for energy storage.