An absorber with photocatalysis and photo-thermal conversion and a preparation method thereof

Abstract

The application discloses an absorber with photocatalysis and photo-thermal conversion functions and a preparation method thereof, which comprises a substrate, a metal reflection layer arranged on the surface of the substrate, two photocatalysis layers arranged on the surface of the metal reflection layer in sequence, and a metal interference layer arranged between the two photocatalysis layers; the two photocatalysis layers are titanium dioxide layer I and titanium dioxide layer II; the titanium dioxide layer I is arranged on the metal reflection layer; the metal interference layer is arranged on the titanium dioxide layer I; and the titanium dioxide layer II is arranged on the metal interference layer. The absorber can absorb wide wavelength light waves in sunlight, can absorb heat in sunlight, can absorb light waves in ultraviolet bands for photocatalysis, has excellent absorption performance in visible light and near infrared regions, and thus has the functions of photocatalysis and photo-thermal conversion, and can significantly improve the utilization efficiency of sunlight.

Description

Technical Field

[0001] This invention relates to the field of optical thin film technology, specifically to an absorber that combines photocatalysis and photothermal conversion, and its preparation method. Background Technology

[0002] In recent years, with the large-scale use of fossil fuels, energy reserves have gradually decreased. To reduce dependence on fossil fuels, researchers have developed various new energy sources, such as wind power, solar power, and tidal power. Among them, solar energy is the new energy source with the most abundant energy and the widest range. Researchers can use solar energy for photocatalytic hydrogen production and photothermal heating. However, existing light absorbers have low utilization rates of the solar spectrum and generally only have one of the functions of photocatalysis or photothermal conversion, resulting in low working efficiency. Summary of the Invention

[0003] To address the problems existing in the prior art, an absorber that combines photocatalysis and photothermal conversion, and its preparation method, are provided.

[0004] The technical solution adopted by this invention to solve its technical problem is:

[0005] This invention proposes an absorber that combines photocatalysis and photothermal conversion, comprising a substrate, a metal reflective layer disposed on the surface of the substrate, two photocatalytic layers disposed sequentially on the surface of the metal reflective layer, and a metal interference layer disposed between the two photocatalytic layers.

[0006] Preferably, the two photocatalytic layers are titanium dioxide layer I and titanium dioxide layer II.

[0007] Preferably, the titanium dioxide layer I is disposed on the metal reflective layer, the metal interference layer is disposed on the titanium dioxide layer I, and the titanium dioxide layer II is disposed on the metal interference layer.

[0008] Preferably, the metal reflective layer contains elements of silver, gold, and aluminum.

[0009] Preferably, the metal interference layer is composed of titanium.

[0010] Preferably, the thickness of the metal reflective layer is 200 nanometers to 400 nanometers.

[0011] Preferably, the thickness of the titanium dioxide layer I is 35 nanometers to 40 nanometers.

[0012] Preferably, the thickness of the metal interference layer is 20 nanometers to 30 nanometers.

[0013] Preferably, the thickness of the titanium dioxide layer II is 35 nanometers to 45 nanometers.

[0014] This invention also proposes a method for preparing an absorber that combines photocatalysis and photothermal conversion, using the aforementioned absorber that combines photocatalysis and photothermal conversion, comprising the following steps:

[0015] S1: The metal reflective layer was completed by magnetron sputtering and covered the substrate surface. The magnetron sputtering used a silver target with a diameter of 75 mm. The sputtering atmosphere was pure argon with a flow rate of 30 sccm, a working pressure of 0.4 Pa, a sputtering power of 120 W, and a sputtering time of 2 minutes. The thickness of the metal reflective layer was 200 nanometers.

[0016] S2: Titanium dioxide layer I was completed by magnetron sputtering and covered the surface of the metal reflective layer. The magnetron sputtering used a titanium dioxide ceramic target with a target diameter of 75 mm. The sputtering atmosphere was a mixture of argon and oxygen with a flow rate of 30 sccm, a working pressure of 0.4 Pa, a sputtering power of 200 W, and a sputtering time of 20 minutes. The thickness of titanium dioxide layer I was 35 nanometers.

[0017] S3: The metal interference layer was completed by magnetron sputtering and covered the surface of titanium dioxide layer I. A titanium target with a diameter of 75 mm was used for magnetron sputtering. The sputtering atmosphere was pure argon with a total flow rate of 30 sccm, a working pressure of 0.4 Pa, a sputtering power of 200 W, and a sputtering time of 15 minutes. The thickness of the metal interference layer was 25 nanometers.

[0018] S4: Titanium dioxide layer II was fabricated by magnetron sputtering, covering the surface of the metal interference layer. A titanium dioxide ceramic target with a diameter of 75 mm was used for magnetron sputtering. The sputtering atmosphere was a mixture of argon and oxygen with a total flow rate of 30 sccm, a working pressure of 0.4 Pa, a sputtering power of 200 W, and a sputtering time of 23 minutes, resulting in a titanium dioxide layer II with a thickness of 40 nanometers.

[0019] Compared with the prior art, the beneficial effects of the present invention are:

[0020] 1. The absorber provided in this invention allows incident light to be reflected multiple times between the photocatalytic layers under the combined effect of the metal reflective layer and the metal interference layer, forming interference, which can effectively enhance light absorption. At the same time, it further increases the optical absorption of the photocatalytic layer, improves the photocatalytic performance, and also has excellent absorption performance in the visible and near-infrared regions. In addition, it has photocatalytic performance and can significantly improve the utilization efficiency of sunlight.

[0021] 2. This invention develops a novel absorber that absorbs sunlight with a wide wavelength range. It can not only absorb heat from sunlight, but also absorb ultraviolet light waves for photocatalysis. Therefore, it has both photocatalytic and photothermal conversion functions, resulting in high solar energy utilization. Attached Figure Description

[0022] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0023] Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0024] Explanation of reference numerals in the attached figures:

[0025] 1. Substrate; 2. Metal reflective layer; 3. Titanium dioxide layer I; 4. Metal interference layer; 5. Titanium dioxide layer II. Detailed Implementation

[0026] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0027] Reference Appendix Figure 1 This embodiment proposes an absorber that combines photocatalysis and photothermal conversion, including a substrate 1, a metal reflective layer 2 disposed on the surface of the substrate 1, two photocatalytic layers disposed sequentially on the surface of the metal reflective layer 2, and a metal interference layer 4 disposed between the two photocatalytic layers.

[0028] The absorber exhibits an average absorptivity greater than 91% in the visible and near-infrared regions, and an infrared emissivity less than 5%. Under simulated sunlight, the photocatalytic current exceeds 60 μA / cm². 2 .

[0029] The substrate 1 may be made of flexible transparent polyethylene terephthalate, glass, or silicon wafers.

[0030] In this application, glass is preferred as the substrate for preparing the absorber.

[0031] The two photocatalytic layers are titanium dioxide layer I3 and titanium dioxide layer II5, both of which are composed of titanium dioxide.

[0032] Titanium dioxide layer I3 is arranged on metal reflective layer 2, metal interference layer 4 is arranged on titanium dioxide layer I3, and titanium dioxide layer II5 is arranged on metal interference layer 4.

[0033] The metal reflective layer 2 contains elements such as silver, gold, and aluminum. In this application, silver is preferably used for the metal reflective layer 2.

[0034] The metal interference layer 4 is composed of titanium.

[0035] The thickness of the metal reflective layer 2 is 200 nanometers to 400 nanometers.

[0036] The titanium dioxide layer I3 has a thickness of 35 nanometers to 40 nanometers.

[0037] The thickness of the metal interference layer 4 is 20 nanometers to 30 nanometers.

[0038] The titanium dioxide layer II5 has a thickness of 35 nm to 45 nm.

[0039] This invention also proposes a method for preparing an absorber that combines photocatalysis and photothermal conversion. Using the absorber described in this embodiment, the method includes the following steps:

[0040] S1: The metal reflective layer was completed by magnetron sputtering and covered the substrate surface. The target material used for magnetron sputtering was a 99.99% pure silver target with a diameter of 75 mm. The sputtering atmosphere was pure argon with a flow rate of 30 sccm, a working pressure of 0.4 Pa, a sputtering power of 120 W, and a sputtering time of 2 minutes. The thickness of the metal reflective layer was 200 nanometers.

[0041] S2: Titanium dioxide layer I was fabricated by magnetron sputtering and covered the surface of the metal reflective layer. The target material used for magnetron sputtering was a titanium dioxide ceramic target with a diameter of 75 mm. The sputtering atmosphere was a mixture of argon and oxygen (32:2) with a flow rate of 30 sccm, a working pressure of 0.4 Pa, a sputtering power of 200 W, and a sputtering time of 20 minutes. The thickness of titanium dioxide layer I was 35 nm.

[0042] S3: The metal interference layer was formed by magnetron sputtering and covered the surface of titanium dioxide layer I. The target material used for magnetron sputtering was a titanium target with a purity of 99.99% and a diameter of 75 mm. The sputtering atmosphere was pure argon with a total flow rate of 30 sccm, a working pressure of 0.4 Pa, a sputtering power of 200 W, and a sputtering time of 15 minutes. The thickness of the metal interference layer was 25 nanometers.

[0043] S4: Titanium dioxide layer II was fabricated by magnetron sputtering, covering the surface of the metal interference layer. The target material used for magnetron sputtering was a titanium dioxide ceramic target with a diameter of 75 mm. The sputtering atmosphere was a mixture of argon and oxygen (32:2), with a total flow rate of 30 sccm, a working pressure of 0.4 Pa, a sputtering power of 200 W, and a sputtering time of 23 minutes. The resulting titanium dioxide layer II had a thickness of 40 nanometers.

[0044] Experiments have shown that the above-mentioned absorber has an average absorption rate of 92% in the visible and near-infrared regions and an infrared emissivity of 4.5%. Under simulated sunlight, the photocatalytic current is 68 μA / cm². 2 .

[0045] Under the combined effect of the reflection of the metal reflective layer 2 and the metal interference layer 4, the incident light is reflected multiple times between the two photocatalytic layers, forming interference, which can effectively enhance light absorption. At the same time, it further increases the optical absorption of the photocatalytic layer and improves the photocatalytic performance.

[0046] The absorber in this invention can absorb a wide range of wavelengths of light in sunlight. It can not only absorb heat from sunlight, but also absorb ultraviolet light for photocatalysis. It has excellent absorption performance in the visible and near-infrared regions. Therefore, it has both photocatalytic and photothermal conversion functions, which can significantly improve the utilization efficiency of sunlight.

[0047] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. An absorber combining photocatalysis and photothermal conversion, comprising a substrate (1), characterized in that, The substrate (1) has a metal reflective layer (2) arranged on its surface. Two photocatalytic layers are arranged sequentially on the surface of the metal reflective layer (2), and a metal interference layer (4) is arranged between the two photocatalytic layers. The two photocatalytic layers are titanium dioxide layer I (3) and titanium dioxide layer II (5); The metal reflective layer (2) contains silver, gold and aluminum. The metal interference layer (4) is composed of titanium. The thickness of the metal reflective layer (2) is 200 nanometers to 400 nanometers; The thickness of the titanium dioxide layer I (3) is 35 nanometers to 40 nanometers; The thickness of the metal interference layer (4) is 20 nanometers to 30 nanometers; The thickness of the titanium dioxide layer II (5) is 35 nanometers to 45 nanometers.

2. The absorber combining photocatalysis and photothermal conversion according to claim 1, characterized in that, The titanium dioxide layer I (3) is arranged on the metal reflective layer (2), the metal interference layer (4) is arranged on the titanium dioxide layer I (3), and the titanium dioxide layer II (5) is arranged on the metal interference layer (4).

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