Application of Ag-Cu nanosheet as self-heating material

Abstract

The invention relates to an application of an Ag-Cu nanosheet as a self-heating material. The Ag-Cu nanosheet is used as a self-heating coating and is coated on the substrate. The Ag-Cu nanosheet efficiently realizes photothermal conversion through a localized surface plasmon resonance (LSPR) effect. When incident light excites free electrons to oscillate collectively, energy is converted into heat energy through non-radiative relaxation (electron-phonon scattering), so that the temperature of the nanosheet is increased within a short time. Heat energy is uniformly transferred to the surface of the substrate, so that the temperature is higher than the ambient temperature, water vapor is prevented from condensing on the surface of the substrate, and the self-heating anti-fog function is realized. And preparing a silicon dioxide encapsulation layer on the surface of the functional coating through a vacuum evaporation coating process. Visible light (400-700 nm) in the environment is efficiently captured through the nanosheets, light energy is converted into heat energy through the LSPR effect, and the fogging problem caused by temperature difference between lenses or glass and surrounding air is solved.

Description

Technical Field

[0001] The invention relates to the use of Ag-Cu nanosheets as a self-heating material, in particular to the use of the Ag-Cu nanosheets as the self-heating material coated on the surface of a spectacle lens to provide an anti-fog lens with a self-heating function. Background Art

[0002] Glasses fog up due to a temperature difference between the lens and the surrounding environment, causing water vapor to condense into tiny droplets that scatter light. Existing anti-fog technologies primarily rely on hydrophobic coatings (such as silica nanocoatings) or chemical hydrophilic coatings, but these suffer from poor durability and the need for repeated application. Electric heating anti-fog solutions, on the other hand, require an external power source and are complex. Summary of the Invention

[0003] To overcome the shortcomings of the prior art, the present invention provides the use of Ag-Cu nanosheets as self-heating materials. The Ag-Cu alloy nanosheets are synthesized by a soft template method, and the preparation method is described in "Ag–Cu filled nanonets with ultrafine dual-nanozyme active units for neurotransmitter biosensing" (Biosensors and Bioelectronics, 250(2024)116033). In this article, the Ag-Cu nanosheets are used as neurotransmitter biosensors based on their ultrafine dual-action nanozymes. During subsequent research and development, the inventor's research team surprisingly discovered that the Ag-Cu nanosheets efficiently achieve photothermal conversion through the localized surface plasmon resonance (LSPR) effect. When incident light excites the collective oscillation of their free electrons, the energy is converted into heat energy through nonradiative relaxation (electron-phonon scattering), causing the nanosheets to heat up in a short period of time. The heat energy is evenly transferred to the lens surface, raising the temperature above the ambient temperature, preventing water vapor condensation and achieving self-heating and anti-fogging functions.

[0004] Based on the above findings, the present invention provides use of Ag-Cu nanosheets as a self-heating material.

[0005] The application is to coat the Ag-Cu nanosheets on a substrate with a self-heating coating, and the substrate is a spectacle lens (resin sheet), automobile glass or window glass.

[0006] Based on the use of the above-mentioned Ag-Cu nanosheets as self-heating materials, the present invention provides an anti-fog lens or anti-fog glass, in which Ag-Cu nanosheets are applied as a functional coating on the surface of the lens, or the surface of automobile glass or window glass.

[0007] Specifically, Ag-Cu nanosheets can absorb visible light in the environment based on the LSPR effect.

[0008] The Ag-Cu nanosheets are oval and circular, with a thickness of 1 to 3 nm and a diameter of 3 to 5 nm. A gap of 1 to 3 nm is left between each Ag-Cu alloy nanosheet, so that the entire Ag-Cu alloy material has good dispersibility and uniform material distribution.

[0009] To further enhance anti-fog performance, the present invention incorporates a silica encapsulation layer on the surface of the functional coating. This encapsulation layer has a dual function: on the one hand, its hydrophobic properties (water contact angle greater than 110°) effectively reduce the adhesion of water droplets; on the other hand, it acts as a protective layer to prevent oxidation of the underlying nanomaterials.

[0010] The preparation method of anti-fog glasses or anti-fog glass comprises the following steps: (1) Ag-Cu alloy nanosheets were synthesized by soft template method: 2 mL formaldehyde solution, 200 mg PVP and 50 mg Tris were added to the polytetrafluoroethylene liner in sequence, stirred and mixed, and then reacted in an oven at 200 °C for 3 hours. The reaction product was purified by centrifugation with acetone and dried in a vacuum at 70 °C to obtain a precursor. The precursor was then dissolved in 2 mL formamide, 0.0026 g copper acetylacetonate, 0.002 g silver acetylacetonate and 0.025 g KI were added, stirred for 1 hour, and reacted in an oven at 130 °C for 3 hours to finally obtain the target product. The physical properties are shown in FIG. Figure 3 .

[0011] (2) The Ag-Cu alloy nanosheets obtained in step (1) are coated on the surface of the substrate by spin coating, with the gap between each Ag-Cu alloy nanosheet being 1-3 nm. The spin coating steps are as follows: the substrate is fixed on the spin coater chuck to ensure that it is level. 50-200 μL of Ag-Cu alloy nanosheet solution is added dropwise to the center of the substrate using a pipette, and the Ag-Cu alloy nanosheet solution is rotated at 3000-4000 rpm to form a film, and finally dried and solidified at below 80°C.

[0012] (3) A silicon dioxide encapsulation layer is prepared on the surface of the functional coating by vacuum evaporation coating process. Beneficial effects

[0013] (1) Ag-Cu alloy nanosheets have strong oxidation resistance. The nanosheets synthesized by the soft template method are evenly dispersed. This synthesis process ensures the monodispersity of the nanosheets (PDI < 0.1), avoids the attenuation of LSPR performance caused by agglomeration, and has the characteristics of long-term stability.

[0014] (2) The coating thickness is less than 500 nm, and the lens is ultra-thin and transparent, which does not affect the lens transmittance and wearing aesthetics. In addition, the photothermal effect can be triggered by ambient light, without the need for an external power supply or regular application of anti-fog agent. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a cross-sectional view of the anti-fog lens of Example 1.

[0016] Figure 2 is a schematic diagram of the functional coating 102 .

[0017] Figure 3 Transmission electron microscopy (TEM) image of Ag-Cu nanosheets (A) and high-resolution transmission electron microscopy (HRTEM) image (B) Figure 4 This is the UV absorption spectrum of Ag-Cu nanosheets.

[0018] Description of main reference numerals: substrate 101 , functional coating 102 , protective layer 103 , Ag—Cu ultrathin alloy nanosheet 104 . DETAILED DESCRIPTION

[0019] The embodiments of the present invention are described below with reference to the accompanying drawings: Example

[0020] like Figure 1 As shown, the anti-fog eyeglass lens comprises, from the inside out, a substrate 101, a functional coating 102, and a protective layer 103. In this embodiment, the substrate is a conventional resin lens; the functional coating is a transparent light-to-heat conversion layer composed of ultra-thin Ag-Cu alloy nanosheets with a thickness of 1-3 nm and a diameter of 3-5 nm, synthesized using a soft template method and uniformly covering the substrate surface; the protective layer is a silicon dioxide encapsulation layer.

[0021] Ag-Cu alloy nanosheets were synthesized using a soft template method. The preparation method has been published in Biosensors and Bioelectronics, 250(2024)116033. With the support of the soft template, the Ag-Cu nanosheets stably maintain an ultrafine two-dimensional structure with high monodispersity, making them suitable for self-heating coating materials for defogging eyeglasses. The functional coating is formed on the surface of a resin lens by spin coating.

[0022] The silica encapsulation layer is deposited on the functional coating through a vacuum evaporation process, forming a dense, uniform protective layer. The vacuum environment prevents oxidation contamination, allowing the silica purity to exceed 99.99%. A substrate rotation system ensures film thickness uniformity within a tolerance of approximately 3%. This layer's thickness is precisely controlled at 50-100nm, ensuring both excellent optical transparency (visible light transmittance >95%) and good mechanical strength.

[0023] In other embodiments, the inventors replaced conventional resin lenses with automobile glass or window glass to prepare anti-fog automobile glass or residential glass, and the preparation method was the same.

[0024] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0025] The preferred embodiments of the present invention are described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, various equivalent transformations can be made to the technical solutions of the present invention, and these equivalent transformations all fall within the scope of protection of the present invention.

Claims

1. Use of Ag-Cu nanosheets as self-heating materials.

2. The use according to claim 1, wherein the Ag-Cu nanosheets are coated on a substrate with a self-heating coating.

3. The use according to claim 2, wherein the substrate is a spectacle lens, automobile glass or residential window glass.

4. An anti-fog eyeglass lens, characterized in that: Ag-Cu nanosheets are applied as functional coatings on the surface of eyeglass lenses. Ag-Cu nanosheets efficiently realize light-to-heat conversion through the localized surface plasmon resonance effect. When the incident light excites the collective oscillation of its free electrons, the energy is converted into heat energy through non-radiative relaxation, causing the nanosheets to heat up in a short time. The heat energy is evenly transferred to the surface of the lens, making the temperature higher than the ambient temperature, preventing water vapor condensation, and realizing self-heating and anti-fog function.

5. The anti-fog spectacle lens according to claim 4, characterized in that: The Ag-Cu nanosheets are nearly circular, with a thickness of 1 to 3 nm and a diameter of 3 to 5 nm. There is a gap of 1 to 3 nm between each Ag-Cu nanosheet, so that the entire Ag-Cu alloy material has good dispersibility and uniform material distribution.

6. The anti-fog spectacle lens according to claim 4, characterized in that: A silicon dioxide encapsulation layer is also provided outside the Ag-Cu nanosheet layer.

7. The method for preparing an anti-fog spectacle lens according to claim 6, wherein: Here are the steps: (1) Ag-Cu nanosheets were synthesized using a soft template method: formaldehyde, PVP, and Tris were added to a polytetrafluoroethylene liner in sequence, stirred and mixed, and then reacted in an oven at 200°C for 3 hours; the reaction product was purified by centrifugation with acetone and vacuum dried to obtain a precursor; the precursor was then dissolved in formamide, and copper acetylacetonate, silver acetylacetonate, and KI were added, stirred evenly, and then reacted in an oven at 130°C for 3 hours to finally obtain the target product; (2) coating the Ag-Cu alloy nanosheets obtained in step (1) on the surface of the substrate by spin coating, with the gap between each Ag-Cu alloy nanosheet being 1-3 nm; (3) A silicon dioxide encapsulation layer is prepared on the surface of the functional coating by vacuum evaporation coating process. 8.An anti-fog glass, characterized in that: Ag-Cu nanosheets are applied as functional coatings to the surface of automobile glass or window glass. Ag-Cu nanosheets efficiently realize light-to-heat conversion through the localized surface plasmon resonance effect. When the incident light excites the collective oscillation of its free electrons, the energy is converted into heat energy through non-radiative relaxation, causing the nanosheets to heat up in a short time. The heat energy is evenly transferred to the lens surface, making the temperature higher than the ambient temperature, preventing water vapor condensation, and realizing self-heating anti-fog function.

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