A method for preparing MXene two-dimensional transition metal carbonitride based on fruit peel waste
By utilizing fruit peel waste for high-temperature dry preparation of MXene, the safety hazards and high costs of existing technologies have been solved, achieving low-cost and environmentally friendly MXene preparation and expanding its application prospects.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- DONGHUA UNIV
- Filing Date
- 2024-03-08
- Publication Date
- 2026-06-16
AI Technical Summary
Existing methods for preparing MXene pose safety risks, environmental pollution, and high costs. In particular, the dangers and high costs associated with etching Ti3AlC2 with acid solutions limit its large-scale application.
MXene is prepared by using fruit peel waste as raw material through a dry method of pre-carbonization and high-temperature calcination after mixing with transition metal salts. This avoids the use of acid and alkali solutions, reduces costs, and expands application prospects.
This paper presents a low-cost, environmentally friendly method for preparing MXene, which simplifies the preparation process, reduces the cost of the final product, and broadens the application value of MXene.
Smart Images
Figure CN118306997B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of MXene, and specifically relates to a method for preparing two-dimensional transition metal carbonitrides of MXene based on fruit peel waste. Background Technology
[0002] Two-dimensional materials, MXenes, have attracted widespread attention since their discovery at Derekjavik University in 2011 due to their unique structure and excellent properties. The preparation of MXenes mostly involves etching their precursor MAX phases, where M represents a transition metal element in the periodic table, A is a main group element, typically Al or Si, and X is C or N. The MXene family is rich in variety; chemical etching reveals abundant functional groups on their surface, and post-processing can further manipulate these functional groups, leading to diverse material properties. Thanks to the outstanding electronic, optical, and biocompatibility properties of MXenes, they have wide applications in numerous fields, including energy storage, electromagnetic shielding, sensing, and biomedicine.
[0003] Most of the currently published patents use chemical etching to prepare MXene. For example, patent CN116835593A uses CuCl2 to etch the Al component in the MAX phase material; patent CN 116553553A uses hydrofluoric acid (HF) and hydrochloric acid (HCl) for chemical stripping; patents CN 116864325A, CN 115411098A, and CN 115520869A use a mixture of titanium aluminum carbon (Ti3AlC2) powder with lithium fluoride (LiF) and HCl solution for wet etching of the MAX phase; patent CN114394595B uses HF for chemical etching; and patent CN 116514076A uses HCl, hydroiodic acid (HI), and hydrobromic acid (HBr) for chemical etching. Additionally, patent CN 113735124B obtains MXene by reacting Ti3AlC2 with NaOH in a high-temperature vacuum environment. While these methods have all yielded high-performance MXene materials, the use of acid or alkali solutions during the preparation process poses certain safety risks, and the large amount of waste acid or alkali solutions generated during chemical etching can pollute the environment.
[0004] Patent CN 113479887 A describes a high-temperature composite preparation of Ti3C2 MXene material with excellent thermal stability, using melamine as a carbon source and Ti3C2. This method differs from the wet chemical etching method used in the aforementioned patents, belonging to a dry method for MXene preparation. Most of the above patents use Ti3AlC2 as a raw material to prepare MXene, but Ti3AlC2 is expensive (50-100 RMB / gram), and the market price of the resulting MXene is about 50 times that of the raw material, thus greatly restricting the large-scale application of MXene materials.
[0005] Currently, the most widely used method for obtaining MXene is to use acid solutions, such as HF, to etch the MAX phase. Ti3C2 is obtained by etching away the Al layer in Ti3AlC2 with acid solution. However, MXene sheets prepared by this method often contain defects, which can affect their performance. Furthermore, acid solutions are highly toxic and corrosive, posing significant risks during the preparation process and causing considerable environmental harm. Additionally, experimental parameters such as temperature, acid concentration, and reaction time are difficult to control. Therefore, there is a need to develop a new, more environmentally friendly method for preparing MXene. Summary of the Invention
[0006] To address the shortcomings of existing technologies, the technical problem to be solved by this invention is to provide a method for preparing MXene two-dimensional transition metal carbonitrides based on fruit peel waste.
[0007] This invention provides a method for preparing two-dimensional transition metal carbonitride MXene, comprising:
[0008] (1) Under an inert atmosphere, the peel was pre-carbonized to obtain a pre-carbonized sample;
[0009] (2) The pre-carbonized sample was mixed with a transition metal salt, ground, and calcined to obtain the two-dimensional transition metal carbonitride MXene.
[0010] Preferably, the inert atmosphere in step (1) includes at least one of argon atmosphere and nitrogen atmosphere;
[0011] For example, argon atmosphere is used to prepare two-dimensional transition metal carbides, and nitrogen atmosphere is used to prepare two-dimensional transition metal carbonitrides.
[0012] The fruit peel is derived from fruit or low-value fruit peel waste; wherein the fruit peel waste is obtained by peeling off the white outer layer of the fruit peel waste.
[0013] The fruit peels include, but are not limited to, one or more of the following: coconut shells, banana peels, orange peels, tangerine peels, pomegranate peels, and lemon peels.
[0014] Preferably, the peel in step (1) is a pre-treated peel; wherein the pre-treatment specifically includes: cutting the peel into small pieces and then removing the moisture;
[0015] More preferably, the removal of moisture includes: after washing, placing the container in a refrigerator to freeze for 12 to 72 hours, and then placing it in a freeze dryer for 3 to 6 hours to dry it.
[0016] Preferably, the pre-carbonization treatment in step (1) is as follows: place it in a furnace, heat it to 400-600°C, and keep it at that temperature for 1-3 hours; after the pre-carbonization treatment, cool it down to room temperature.
[0017] Preferably, the heating rate is 5-15°C / min; the cooling rate to room temperature is controlled at 5-20°C / min.
[0018] Preferably, in step (2), the mass ratio of the pre-carbonized sample to the transition metal salt is 0.5:1 to 2:1; the pre-carbonized sample is a ground pre-carbonized sample; wherein the grinding can be done by using a pestle and mortar for uniform grinding.
[0019] Preferably, the transition metal salt in step (2) is an ammonium salt containing a transition metal; wherein the transition metal includes one or more of molybdenum (Mo), vanadium (V), chromium (Cr), tungsten (W), and rhenium (Re).
[0020] Preferably, in step (2), the calcination is carried out by placing the sample in a furnace, heating it to 700–900°C, and holding it at that temperature for 1–3 hours; after calcination, the sample is cooled to room temperature; the calcination is carried out in an inert atmosphere. The inert atmosphere includes at least one of argon atmosphere and nitrogen atmosphere.
[0021] Preferably, the heating rate to 700-900℃ is controlled at 5-15℃ / min; the cooling rate to room temperature is controlled at 5-20℃ / min.
[0022] This invention provides a two-dimensional transition metal carbonitride MXene prepared by the method described above.
[0023] This invention aims to develop a new low-cost method for preparing MXene, specifically including using inexpensive fruit peel waste as raw material to replace the MAX phase precursor, and employing a high-temperature dry preparation method, which greatly shortens the preparation process of the wet chemical etching method (the two preparation processes are as follows). Figure 1 As shown in the figure, this reduces the cost of the final product—two-dimensional transition metal carbonitrides—expands the application value of MXene, and broadens its application prospects.
[0024] Beneficial effects
[0025] This invention provides a method for preparing two-dimensional transition metal carbonitrides MXene from fruit peel waste. The preparation process is not only environmentally friendly, but also uses inexpensive raw materials, making it suitable for large-scale preparation of MXene and facilitating its widespread application in various fields.
[0026] Compared with existing technologies, this invention has lower raw material costs, a simpler preparation process, and achieves sustainable development and utilization of resources, providing a low-cost method for preparing two-dimensional transition metal carbonitrides (MXenes). Attached Figure Description
[0027] Figure 1 The existing technical route (left) and the preparation process of this patent (right);
[0028] Figure 2 This is a schematic diagram of the preparation process of MXene two-dimensional transition metal carbonitrides;
[0029] Figure 3 The XRD pattern of the Mo2C sample;
[0030] Figure 4 The Raman spectrum of the Mo2C sample;
[0031] Figure 5 SEM images of Mo2C samples; (A) Example 1; (B) Example 2; (C) Example 3. Detailed Implementation
[0032] The present invention will be further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims.
[0033] Example 1
[0034] A method for preparing two-dimensional transition metal carbonitrides—Mo2C—from fruit peel waste includes the following steps:
[0035] Orange peel waste from the supermarket was washed with deionized water, frozen in a refrigerator for 48 hours, and then dried in a freeze dryer for 6 hours. It was then cut into small pieces. Under an argon atmosphere, the small pieces of orange peel were placed in a furnace. The temperature was controlled to rise at a rate of 10℃ / min to 500℃, held for 1 hour, and then cooled to room temperature to obtain a pre-carbonized orange peel sample.
[0036] The pre-carbonized orange peel sample was ground evenly using a pestle and mortar. 0.5g of the pre-carbonized orange peel sample and 0.5g of ammonium heptamolybdate were weighed and mixed, and the mixture was ground evenly. Under an argon atmosphere, the sample was placed in a furnace. The heating rate was controlled at 10℃ / min to reach 850℃, and the temperature was maintained for 1 hour. The sample was then cooled to room temperature to obtain the Mo2C sample.
[0037] Example 2
[0038] Banana peel waste from supermarkets was washed with deionized water, frozen in a refrigerator for 48 hours, and then dried in a freeze dryer for 6 hours. The dried banana peel was then cut into small pieces. Under an argon atmosphere, the banana peel pieces were placed in a furnace. The temperature was controlled to rise at a rate of 10℃ / min to 500℃, held for 1 hour, and then allowed to cool naturally to room temperature to obtain pre-carbonized banana peel samples.
[0039] The pre-carbonized banana peel sample was ground evenly using a pestle and mortar. 0.5g of the pre-carbonized banana peel sample and 0.5g of ammonium heptamolybdate were weighed and mixed, and the mixture was ground evenly. Under an argon atmosphere, the sample was placed in a tube furnace. The heating rate was controlled at 10℃ / min to reach 850℃, and the temperature was maintained for 1 hour. The sample was then allowed to cool naturally to room temperature to obtain the Mo2C sample.
[0040] Example 3
[0041] Coconut shell waste from a supermarket was washed with deionized water, frozen in a refrigerator for 48 hours, and then dried in a freeze dryer for 6 hours. The dried shells were then cut into small pieces. Under an argon atmosphere, the small pieces of coconut shell were placed in a furnace. The heating rate was controlled at 10℃ / min to 500℃, held for 1 hour, and then allowed to cool naturally to room temperature to obtain pre-carbonized coconut shell samples.
[0042] The pre-carbonized coconut shell sample was ground evenly using a pestle and mortar. 0.5g of the pre-carbonized coconut shell sample was weighed and mixed with 0.5g of ammonium heptamolybdate, and the mixture was ground evenly. Under an argon atmosphere, the sample was placed in a furnace. The heating rate was controlled at 10℃ / min to reach 850℃, and the temperature was maintained for 1 hour. The sample was then allowed to cool naturally to room temperature to obtain the Mo2C sample.
[0043] The obtained Mo2C sample was subjected to X-ray diffraction (XRD) testing. The XRD pattern of the Mo2C sample (e.g.) Figure 3 The results show that there are obvious diffraction peaks at 34.4° (100), 37.9° (002), 40.4° (101), 52.1° (102), 61.6° (110), 69.6° (103), 74.6° (112) and 75.7° (201), which correspond to the hexagonal crystal structure of β-Mo2C (JCPDS#11-0680).
[0044] Raman spectroscopy was performed on the obtained Mo2C sample (e.g. Figure 4The Raman spectrum of the Mo2C sample at 1350 cm⁻¹ -1 and 1580cm -1 There are two different peaks, corresponding to the characteristics of metal carbides.
[0045] Scanning electron microscope (SEM) images (such as Figure 5 This demonstrates that the Mo2C samples prepared from the three raw materials have a distinct two-dimensional sheet structure.
Claims
1. A method for preparing a two-dimensional transition metal carbonitride MXene, comprising: (1) Under inert atmosphere conditions, the peel was pre-carbonized to obtain a pre-carbonized sample; The pre-carbonization process involves heating to 400-600℃ and holding for 1-3 hours; after the pre-carbonization process, the temperature is then lowered to room temperature. (2) The pre-carbonized sample was mixed with a transition metal salt, ground, and calcined to obtain two-dimensional transition metal carbonitride MXene.
2. The preparation method according to claim 1, characterized in that, The inert atmosphere in step (1) includes at least one of argon atmosphere and nitrogen atmosphere; the fruit peel is derived from fruit or fruit peel waste; The peel includes one or more of the following: coconut shell, banana peel, orange peel, tangerine peel, pomegranate peel, and lemon peel.
3. The preparation method according to claim 1, characterized in that, In step (1), the peel is the pre-treated peel; The pretreatment specifically includes: cutting the peel and then removing the moisture; The moisture removal process includes: freezing in a refrigerator for 12-72 hours, and then placing it in a freeze dryer for 3-6 hours.
4. The preparation method according to claim 1, characterized in that, The heating rate in step (1) is 5~15℃ / min; the cooling rate to room temperature is controlled at 5~20℃ / min.
5. The preparation method according to claim 1, characterized in that, In step (2), the mass ratio of the pre-carbonized sample to the transition metal salt is 0.5:1 to 2:1; the pre-carbonized sample is the pre-carbonized sample after grinding.
6. The preparation method according to claim 1, characterized in that, The transition metal salt in step (2) is an ammonium salt containing a transition metal; wherein the transition metal includes one or more of molybdenum (Mo), vanadium (V), chromium (Cr), tungsten (W), and rhenium (Re).
7. The preparation method according to claim 1, characterized in that, In step (2), the calcination is carried out by heating to 700~900℃ and holding for 1~3 hours; the calcination is carried out in an inert atmosphere; and the temperature is cooled to room temperature after calcination.
8. The preparation method according to claim 7, characterized in that, The heating rate to 700-900℃ is controlled at 5-15℃ / min; the cooling rate to room temperature is controlled at 5-20℃ / min; the inert atmosphere includes at least one of argon atmosphere and nitrogen atmosphere.
9. A two-dimensional transition metal carbonitride MXene prepared by the method of claim 1.