1. MXene-TiO₂The preparation method is characterized by comprising the following steps:

(1) after 10mL of MXene solution is put into an ultrasonic instrument, the ultrasonic instrument is started to process the solution, and PMS is added in the processing process;

(2) MXene-TiO prepared in the step (1)₂Pouring the solution into a centrifuge tube, putting the centrifuge tube into a centrifuge for first centrifugation, taking out the centrifuge tube after the centrifugation is finished, and pouring out supernatant;

(3) washing and precipitating the solution prepared in the step (2), centrifuging for the second time, taking out a centrifuge tube after the centrifugation is finished, pouring out supernatant, and precipitating to obtain MXene-TiO₂。

2. MXene-TiO according to claim 1₂The method of (1), wherein the PMS is prepared in a powder form.

3. MXene-TiO according to claim 2₂The preparation method is characterized in that the mass ratio of MXene to PMS powder in the MXene solution in the step (1) is 1: 25-75.

4. MXene-TiO according to claim 2₂The method for preparing (1), wherein the concentration of the MXene solution in the step (1) is 0.6 mg/mL.

5. MXene-TiO according to claim 3₂The preparation method is characterized in that the ultrasonic treatment time in the step (1) is 10min, and the temperature is 25 ℃.

6. MXene-TiO according to claim 1₂The method for preparing (1), wherein the rotation speed of the centrifuge in the step (2) and the step (3) is set to 12000rpm, and the time is set to 10 min.

Background

MXene-TiO₂Has the advantages of large specific surface area, strong conductivity and the like, and is widely applied to photocatalytic reduction of CO₂Electrode materials, energy sources, heavy metal reduction and adsorption and the like. Thus MXene-TiO₂The preparation of (A) becomes the central importance.

Currently prepared MXene-TiO₂The method mainly comprises a calcination method and an in-situ hydrothermal method.

A calcining method: firstly drying MXene solution in a vacuum environment, placing the obtained MXene powder in a muffle furnace, and calcining for a certain time at 300-700 ℃ to obtain MXene-TiO₂And (3) powder. The method can control the oxidation degree of MXene by controlling the calcination time and the calcination temperature. However, the muffle furnace belongs to a high-power electric appliance, has certain potential safety hazard for electricity utilization, is complex to operate, long in reaction time, inconvenient to collect powder, and high in final product loss.

In-situ hydrothermal method: adding a certain amount of MXene into the prepared deposition solution in advance, and then placing the deposition solution into a hydrothermal reaction kettle. Putting the mixture into a drying oven, heating the mixture for a certain time at the temperature of between 100 and 200 ℃, and finally drying the obtained precipitate to obtain MXene-TiO₂. The method can control MXene-TiO by controlling heating time and temperature₂And MXene-TiO is prepared in one step₂It is simpler than calcining method. But nowadays, the accidents of the reaction kettle are frequent, and the method has larger safety risk.

MXene and TiO may be used₂MXene-TiO preparation by blending method₂This method reduces the risk to some extent, but the reaction time is relatively long.

Disclosure of Invention

The invention mainly aims to provide MXene-TiO which has the advantages of milder condition, short reaction time, simple operation, low cost, high market value and easy popularization and utilization₂A preparation method.

In order to achieve the aim, the invention provides MXene-TiO₂The preparation method comprises the following steps:

(1) after 10mL of MXene solution is put into an ultrasonic instrument, the ultrasonic instrument is started to process the solution, and PMS is added in the processing process;

(2) MXene-TiO prepared in the step (1)₂Pouring the solution into a centrifuge tube, putting the centrifuge tube into a centrifuge for first centrifugation, taking out the centrifuge tube after the centrifugation is finished, and pouring out supernatant;

(3) washing and precipitating the solution prepared in the step (2), centrifuging for the second time, taking out a centrifuge tube after the centrifugation is finished, pouring out supernatant, and precipitating to obtain MXene-TiO₂。

In some embodiments, the PMS is made into powder, and adding PMS powder to the MXene solution enables the two to react more fully.

In some embodiments, the mass ratio of MXene to PMS powder in the MXene solution of step (1) is 1: 25-75.

In some embodiments, the concentration of MXene solution in step (1) is 0.6 mg/mL.

In some embodiments, the sonication time in step (1) is 10min and the temperature is 25 degrees.

In some embodiments, the rotational speed of the centrifuge in steps (2) and (3) is set to 12000rpm for 10 min.

Compared with the prior art, the invention has the beneficial effects that: the MXene-TiO provided by the invention₂The preparation method has the advantages of mild conditions, short reaction time, simple operation, low cost, high market value and easy popularization and utilization.

Detailed Description

The present disclosure is described in detail below with reference to various embodiments, but it should be understood that these embodiments are not intended to limit the present disclosure, and a person skilled in the art may make functional, methodological, or structural equivalent changes or substitutions based on these embodiments within the scope of the present disclosure.

Unless otherwise specified, the term "room temperature" in the examples of the present specification is specifically 25 ℃; the term "h" is in particular a time measurement unit: hours; the term "ml" is in particular a volume unit: ml; the term "g" is a unit of weight, i.e., grams.

MXene has high stability, but Ti atoms in MXene are easily oxidized into titanium oxide under certain conditions, which is the preparation of MXene-TiO by in-situ oxidation₂Providing a theoretical basis.

Example 1

MXene-TiO provided in this example₂The preparation method comprises the following steps:

(1) after 10mL of 0.6mg/mL MXene solution is put into an ultrasonic instrument, the ultrasonic instrument is started to process the solution, the ultrasonic duration is 10min, the temperature is 25 ℃, and 150mg of PMS powder is added in the processing process;

(2) MXene-TiO prepared in the step (1)₂The solution was poured into centrifuge tubes and placed in a centrifuge at 12000rpm for 10 min. Carrying out primary centrifugation, taking out the centrifuge tube after the centrifugation is finished, and pouring out supernatant;

(3) washing the solution prepared in the step (2) for precipitation, and then carrying out secondary centrifugation, wherein the rotation speed of a centrifuge is set to 12000rpm, and the time is set to 10 min; taking out the centrifugal tube after the centrifugation is finished, pouring out the supernatant, and obtaining MXene-TiO after precipitation₂。

Example 2

MXene-TiO provided in this example₂The preparation method comprises the following steps:

(1) after 10mL of 0.6mg/mL MXene solution is put into an ultrasonic instrument, the ultrasonic instrument is started to process the solution, the ultrasonic duration is 10min, the temperature is 25 ℃, and 300mg of PMS powder is added in the processing process;

(2) MXene-TiO prepared in the step (1)₂Pouring the solution into a centrifuge tube, and placing into a centrifuge, wherein the rotation speed of the centrifuge is set to 12000rpm, and the time is set to 10min is the same as the formula (I). Carrying out primary centrifugation, taking out the centrifuge tube after the centrifugation is finished, and pouring out supernatant;

(3) washing the solution prepared in the step (2) for precipitation, and then carrying out secondary centrifugation, wherein the rotation speed of a centrifuge is set to 12000rpm, and the time is set to 10 min; taking out the centrifugal tube after the centrifugation is finished, pouring out the supernatant, and obtaining MXene-TiO after precipitation₂。

Example 3

MXene-TiO provided in this example₂The preparation method comprises the following steps:

(1) after 10mL of 0.6mg/mL MXene solution is put into an ultrasonic instrument, the ultrasonic instrument is started to process the solution, the ultrasonic duration is 10min, the temperature is 25 ℃, and 450mg of PMS powder is added in the processing process;

(2) MXene-TiO prepared in the step (1)₂The solution was poured into centrifuge tubes and placed in a centrifuge at 12000rpm for 10 min. Carrying out primary centrifugation, taking out the centrifuge tube after the centrifugation is finished, and pouring out supernatant;

(3) washing the solution prepared in the step (2) for precipitation, and then carrying out secondary centrifugation, wherein the rotation speed of a centrifuge is set to 12000rpm, and the time is set to 10 min; taking out the centrifugal tube after the centrifugation is finished, pouring out the supernatant, and obtaining MXene-TiO after precipitation₂。

The above example was carried out to prepare MXene-TiO using MXene and PMS powders in different ratios₂. MXene-TiO preparation prepared for 3 kinds of examples₂Flux analysis of the nanofiltration membrane in the middle layer was performed to demonstrate that MXene: the optimal proportion of PMS powder.

Table 1: different MXenes: pure water flux of MXene-TiO2 middle-layer nanofiltration membrane prepared by PMS powder ratio

MXene：PMS powder	1:25	1:50	1:75
				Flux (L.m)-2·h-1·bar-1)	8.84	10.27	9.14

From table 1, it can be seen that when MXene: MXene-TiO prepared when PMS powder is 1:50₂The flux of the middle nanofiltration membrane is the highest flux of all ratios.

What has been described above is merely some embodiments of the present disclosure. It will be apparent to those skilled in the art that various changes and modifications can be made without departing from the inventive concept of the present disclosure, which falls within the scope of the disclosure.