Method for preparing erasable patterns on perovskite quantum dot films

Abstract

The present invention relates to a method for preparing an erasable pattern on a perovskite quantum dot thin film, the method comprising: performing laser direct writing on the perovskite quantum dot thin film to form a first quantum dot pattern; heating the perovskite quantum dot thin film so that the first quantum dot pattern disappears; and performing laser direct writing on the perovskite quantum dot thin film again to form a second quantum dot pattern. The present invention innovatively heats the perovskite quantum dot thin film patterned by laser direct writing, so that the formed quantum dot pattern can be erased, thereby enabling various quantum dot patterns to be repeatedly prepared on the perovskite quantum dot thin film and realizing recycling.

Description

Technical Field

[0001] The present invention relates to the field of laser technology, and in particular, to a method for preparing an erasable pattern on a perovskite quantum dot thin film. Background Art

[0002] Quantum dots have received great attention in applications such as light-emitting diodes, photodetectors, and optical information storage devices due to their high luminous efficiency, high color purity, easy spectral adjustment, and low preparation cost. Quantum dot patterning is potentially important for exploring new functions and applications in optoelectronics.

[0003] Laser direct writing, as a simple, fast, precise, and controllable quantum dot micropatterning technique, has become a research hotspot. However, it is still a challenge to prepare stable and repeatedly reproducible quantum dot patterns using laser direct writing. Summary of the Invention

[0004] The present invention innovatively heats the perovskite quantum dot thin film patterned by laser direct writing, so that the formed quantum dot pattern can be erased, thereby enabling various quantum dot patterns to be repeatedly prepared on the perovskite quantum dot thin film and realizing recycling.

[0005] According to one aspect of the present invention, there is provided a method for preparing an erasable pattern on a perovskite quantum dot thin film, which includes: performing laser direct writing on the perovskite quantum dot thin film to form a first quantum dot pattern; heating the perovskite quantum dot thin film so that the first quantum dot pattern disappears; and performing laser direct writing on the perovskite quantum dot thin film again to form a second quantum dot pattern.

[0006] In an embodiment, the method further includes: repeatedly heating and performing laser direct writing on the perovskite quantum dot thin film having a quantum dot pattern, thereby repeatedly preparing quantum dot patterns on the perovskite quantum dot thin film.

[0007] In an embodiment, heating the perovskite quantum dot thin film includes: heating the perovskite quantum dot thin film at at least 40 degrees Celsius.

[0008] In an embodiment, heating the perovskite quantum dot thin film includes: heating the perovskite quantum dot thin film for at least 1 minute.

[0009] In an embodiment, the first quantum dot pattern is the same as the second quantum dot pattern.

[0010] In an embodiment, the first quantum dot pattern is different from the second quantum dot pattern.

[0011] In an embodiment, the perovskite quantum dot thin film is prepared by an in-situ method.

[0012] In one embodiment, the perovskite quantum dot film includes a transparent matrix and perovskite quantum dots, wherein the perovskite quantum dots are uniformly dispersed in the transparent matrix or coated on the surface of the transparent matrix.

[0013] In one embodiment, the transparent matrix includes PAN, PMMA, PVA, PS, and PVDF, as well as their derivatives.

[0014] In one embodiment, the chemical general formula of the perovskite quantum dots is APbB3, wherein A is CH3NH3, CH4N2, or Cs, and B is I, Cl, or Br.

[0015] Compared with the prior art, one or more embodiments of the above solution may have the following advantages or beneficial effects:

[0016] Innovatively, the present invention heats the perovskite quantum dot film patterned by laser direct writing, so that the formed quantum dot pattern can be erased, thereby enabling various quantum dot patterns to be repeatedly prepared on the perovskite quantum dot film, realizing recycling. The method for preparing an erasable pattern on a perovskite quantum dot film according to the present invention is simple to operate, low in cost, suitable for industrial production, and excellent in stability and cycling performance, and has broad application prospects in the fields of optical encryption and the like.

[0017] Other features and advantages of the present invention will be set forth in the following description, and will be partly apparent from the description, or may be learned by practice of the present invention. The objectives and other advantages of the present invention may be realized and attained by the structure particularly pointed out in the specification, claims, as well as the drawings. Description of the Drawings

[0018] The drawings are used to provide a further understanding of the present invention, and constitute a part of the specification, and together with the embodiments of the present invention are used to explain the present invention, but do not constitute a limitation to the present invention.

[0019] Figure 1 is a flowchart of a method for preparing an erasable pattern on a perovskite quantum dot film according to an embodiment of the present invention.

[0020] Figure 2a 、 2b 、2c and 2d schematically show the changes in the pattern on the perovskite quantum dot film under ultraviolet lamp irradiation.

[0021] Figure 3 shows the relationship between the fluorescence quantum yield of the perovskite quantum dot film and the number of cycles. Detailed Embodiments

[0022] The embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings and examples, so as to fully understand how the present invention uses technical means to solve technical problems and achieve the implementation process of technical effects and implement accordingly. It should be noted that as long as there is no conflict, the various embodiments in the present invention and the various features in each embodiment can be combined with each other, and the formed technical solutions are all within the protection scope of the present invention.

[0023] Meanwhile, in the following description, many specific details are set forth for the purpose of explanation in order to provide a thorough understanding of the embodiments of the present invention. However, it is obvious to those skilled in the art that the present invention may not be implemented with the specific details here or in the specific manner described.

[0024] The perovskite quantum dot film can be prepared by using a variety of methods well known in the art. For example, in one embodiment, it is prepared by an in-situ method, which is simple and convenient and can greatly reduce the preparation process flow of the quantum dot film.

[0025] The prepared perovskite quantum dot film includes a transparent matrix and perovskite quantum dots. The perovskite quantum dots can be uniformly dispersed in the transparent matrix or can be coated on the surface of the transparent matrix. The transparent matrix can be selected from the following transparent resin materials, for example: PAN, PMMA, PVA, PS, and PVDF and their derivatives, etc. The selected transparent resin material can be dissolved in a polar solvent such as DMF. The chemical general formula of the perovskite quantum dots is APbB3, where A can be CH3NH3, CH4N2 or Cs, and B can be I, Cl or Br. By changing B, the absorption spectrum and emission spectrum of the perovskite quantum dots can be adjusted.

[0026] With reference to Figure 1 and Figure 2a 、 2b 、2c and 2d. Figure 1 is a flowchart of a method for preparing an erasable pattern on a perovskite quantum dot film according to an embodiment of the present invention. Figure 2a 、 2b 、2c and 2d schematically show the changes in the pattern on the perovskite quantum dot film under ultraviolet lamp irradiation.

[0027] The method according to an embodiment of the present invention starts with step S101: laser direct writing is performed on the perovskite quantum dot film to form a first quantum dot pattern. Laser direct writing technology is well known in the art. By performing laser direct writing on the surface of the perovskite quantum dot film, the crystal structure of the perovskite quantum dots can be destroyed by using the high-energy and precise focusing effect of the laser, so as to form a predetermined first quantum dot pattern on the perovskite quantum dot film, such as Figure 2a the heart-shaped pattern shown.

[0028] The method according to an embodiment of the present invention is followed by step S102: heating the perovskite quantum dot thin film to make the first quantum dot pattern disappear. The present invention innovatively heats the patterned perovskite quantum dot thin film under certain conditions so that the already formed quantum dot pattern can be erased. By heating under certain conditions, defects can be repaired at the places damaged by the laser, and quantum dots can be regenerated, so that the pattern can be erased.

[0029] In one embodiment, the heating condition can be heating at 40 °C for 1 minute. Refer to Figure 2b and 2c , Figure 2b is the case where the perovskite quantum dot thin film of Figure 2a is heated at 40 °C for 5 seconds, and it can be seen that the heart-shaped pattern becomes thinner; Figure 2c is the case where the perovskite quantum dot thin film of Figure 2a is heated at 40 °C for 1 minute, and it can be seen that the heart-shaped pattern completely disappears.

[0030] In different embodiments, the heating conditions can be different. For example, the heating temperature can be set higher than 40 °C and the heating time can be less than 1 minute, or the heating temperature can be set lower than 40 °C and the heating time can be more than 1 minute, as long as the object of the present invention can be achieved, that is, by heating, quantum dots are regenerated at the places damaged by the laser, so that the pattern can be erased.

[0031] The method according to an embodiment of the present invention then is step S103: performing laser direct writing on the perovskite quantum dot thin film again to form a second quantum dot pattern. Since the pattern on the perovskite quantum dot thin film is erased by thermal recovery in step S102, the perovskite quantum dot thin film can be laser direct written again to form a predetermined second quantum dot pattern, thereby realizing recycling. According to actual needs, the second quantum dot pattern can be different from the first quantum dot pattern or the same as the first quantum dot pattern. For example Figure 2d shows the same heart-shaped pattern as Figure 2a .

[0032] The method according to an embodiment of the present invention may further include: repeatedly heating the patterned perovskite quantum dot thin film and performing laser direct writing on the perovskite quantum dot thin film, so as to repeatedly prepare quantum dot patterns on the perovskite quantum dot thin film.

[0033] Figure 3 shows the relationship between the fluorescence quantum yield of the perovskite quantum dot thin film and the number of cycles. From Figure 3 the test results, it can be seen that after 10 cycles, the fluorescence quantum yield changes from 92% initially to 84%, indicating good cycling performance and basically no reduction in luminous efficiency, which can meet the application requirements in aspects such as anti-counterfeiting and optical information storage.

[0034] The present invention innovatively heats a perovskite quantum dot film patterned by laser direct writing, enabling the erasure of the already formed quantum dot pattern, so that various quantum dot patterns can be repeatedly fabricated on the perovskite quantum dot film, achieving recycling. The method for fabricating an erasable pattern on a perovskite quantum dot film according to the present invention is simple to operate, low in cost, suitable for industrial production, and excellent in stability and cycling performance, and has broad application prospects in fields such as optical encryption.

[0035] It should be understood that the embodiments disclosed in the present invention are not limited to the specific processing steps or materials disclosed herein, but should extend to equivalent alternatives of these features understood by those of ordinary skill in the relevant art. It should also be understood that the terms used herein are for the purpose of describing specific embodiments only and do not imply limitation.

[0036] The "embodiments" mentioned in the specification mean that the specific features or characteristics described in connection with the embodiments are included in at least one embodiment of the present invention. Therefore, the phrase "embodiments" that appears throughout the specification does not necessarily refer to the same embodiment.

[0037] Although the disclosed embodiments of the present invention are as above, the content described is only an embodiment adopted for the convenience of understanding the present invention and is not intended to limit the present invention. Any person skilled in the technical field to which the present invention pertains may make any modifications and changes in the form of implementation and details without departing from the spirit and scope disclosed by the present invention. However, the protection scope of the present invention shall still be subject to the scope defined by the appended claims.

Claims

1. A method for preparing an erasable pattern on a perovskite quantum dot film, comprising: Performing laser direct writing on the perovskite quantum dot film to form a first quantum dot pattern; Heating the perovskite quantum dot film to make the first quantum dot pattern disappear; And Performing laser direct writing on the perovskite quantum dot film again to form a second quantum dot pattern.

2. The method according to claim 1, further comprising: Repeatedly heating and performing laser direct writing on the perovskite quantum dot film having a quantum dot pattern, thereby repeatedly preparing a quantum dot pattern on the perovskite quantum dot film.

3. The method according to claim 1, wherein, Heating the perovskite quantum dot film includes: Heating the perovskite quantum dot film at at least 40 degrees Celsius.

4. The method according to claim 1, wherein Heating the perovskite quantum dot film includes: Heating the perovskite quantum dot film for at least 1 minute.

5. The method according to claim 1, wherein, The first quantum dot pattern is the same as the second quantum dot pattern.

6. The method according to claim 1, wherein, The first quantum dot pattern is different from the second quantum dot pattern.

7. The method according to claim 1, wherein The perovskite quantum dot film is prepared by an in-situ method.

8. The method according to claim 7, wherein The perovskite quantum dot film includes a transparent matrix and perovskite quantum dots, wherein the perovskite quantum dots are uniformly dispersed in the transparent matrix or coated on the surface of the transparent matrix.

9. The method according to claim 8, wherein, The transparent matrix includes PAN, PMMA, PVA, PS, and PVDF, and their derivatives.

10. The method according to claim 8, wherein, The chemical general formula of the perovskite quantum dots is APbB3, wherein A is CH3NH3, CH4N2, or Cs, and B is I, Cl, or Br.

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