A light energy adsorbing material with broad spectrum absorption, a preparation method and application thereof

Abstract

The application belongs to the technical field of light energy adsorbing materials, and particularly relates to a light energy adsorbing material with wide spectrum absorption, a preparation method and application; the preparation method comprises the following steps: S1, putting commercial Ti2O3 powder into a ball mill for ball milling to obtain nano-sized Ti2O3 particles; S2, mixing the nano-sized Ti2O3 particles and nano-sized carbon particles, adding anhydrous ethanol, uniformly stirring, and then putting into an oven for drying to obtain mixed particles; S3, adding polyvinyl alcohol into deionized water, heating to completely dissolve the polyvinyl alcohol, and then cooling to room temperature to obtain a polyvinyl alcohol solution, uniformly coating the polyvinyl alcohol solution on the surface of a treated agate agate block; then spraying the mixed particles on the surface of the agate agate block; S4, coating polydimethylsiloxane on the surface of the agate agate block on which the mixed particles are sprayed, and irradiating with a UV lamp, and then taking out and placing in a drying box for drying to obtain a hydrophobic surface.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of light energy adsorption materials, and particularly relates to a light energy adsorption material with broad spectrum absorption, a preparation method and application. BACKGROUND

[0002] Water is one of the most abundant resources on earth, covering three quarters of the earth's surface, but about 97% of which is salt water, only 3% of which is fresh water suitable for humans, plants and animals. In recent decades, the excessive growth of population, the development of industry and the improvement of living standards have made the world's demand for fresh water reach an unprecedented level. Seawater desalination is one of the important ways to solve the current shortage of fresh water resources. The fresh water produced by this technology can not only be used for urban water, but also be used for various industrial water. At present, the traditional seawater desalination methods include reverse osmosis, low multi-effect, multi-stage flash evaporation, electrodialysis, pressure steam distillation, dew point evaporation method, and water-electricity cogeneration. These methods can be generally divided into two categories: distillation method and membrane method. Among them, reverse osmosis (RO), multi-stage flash evaporation (MSF) and multi-effect distillation (MED) are the global mainstream methods, which have been commercialized. In the distillation method, the heating method can be divided into bottom heating, volume heating and interfacial heating. Compared with the former two, interfacial heating concentrates heat on the surface of the water body, reducing heat loss and the use of photothermal materials. For interfacial heating, the selection of water transport materials and photothermal materials is particularly important. The water transport material should have the ability to quickly transport the water at the bottom to the upper surface of the evaporator. In addition to preparing hydrogels with numerous vertical pores and other pore structures, some biomass materials such as wood, bamboo and rattan also have a large number of small vertical channels with a large capillary pressure, which can effectively transport water vertically. Photothermal materials can effectively absorb solar energy and convert it into heat energy. When sunlight shines on the material surface, part of the sunlight is absorbed, and the other part is reflected back to the environment. The absorbed solar energy is excited to generate heat energy. Part of this heat energy is used for evaporating surface water, and the other part is lost in various forms. An excellent photothermal material will minimize heat loss and use most of it for water evaporation. At the same time, it has a relatively wide range of absorption of solar spectrum. Photothermal materials usually include carbon-based materials, metal materials, polymer materials, semiconductor materials, etc. The selection of different photothermal materials will also affect the light absorption performance of the evaporator.

[0003] At present, desalination technology often needs a large amount of electrical or chemical energy, and the maintenance, installation and operation costs of the equipment are relatively high, which has problems such as large resource consumption, serious environmental pollution and high maintenance cost. At the same time, the traditional evaporator using semiconductor as the light absorption layer has the problem of low light absorption, and the evaporator using carbon-based materials has the problem of low light-heat conversion efficiency. SUMMARY

[0004] The present application provides a light energy adsorbing material with broad spectrum absorption, a preparation method and application.

[0005] The object of the present application can be achieved by the following technical solutions.

[0006] The present application provides a preparation method of a light energy adsorbing material with broad spectrum absorption, which comprises the following steps.

[0007] S1, putting commercial Ti2O3 powder into a ball mill to obtain nano-sized Ti2O3 particles by ball milling;

[0008] S2, mixing the nano-sized Ti2O3 particles and nano-sized carbon particles, adding anhydrous ethanol, stirring uniformly, and then drying in an oven to obtain mixed particles;

[0009] S3, adding polyvinyl alcohol into deionized water, heating to completely dissolve, and then cooling to room temperature to obtain a polyvinyl alcohol solution, uniformly coating the polyvinyl alcohol solution on the surface of the treated agate block, and then spraying the mixed particles on the surface of the agate block;

[0010] S4, coating polydimethylsiloxane on the surface of the agate block sprayed with the mixed particles, and irradiating with a UV lamp, and then taking out and drying in a drying box to obtain a hydrophobic surface.

[0011] Further, in step S1, the particle size of the steel balls in the ball mill is 5-10 mm, the ball milling time is 24 h, the rotation speed is 400 r / min, and the resting time is 10 min.

[0012] Further, in step S2, the mass ratio of the nano-sized Ti2O3 particles and the nano-sized carbon particles is 3-5:1.

[0013] Further, in step S3, the concentration of the prepared polyvinyl alcohol solution is 0.8-1.5 g / ml.

[0014] Further, in step S3, the diameter of the treated agate block is 20 mm, the thickness is 10 mm, and the agate block needs to be polished with sandpaper before coating the polyvinyl alcohol solution.

[0015] Further, in step S3, the coating amount of the polyvinyl alcohol solution is 0.05-0.1 g, the spraying amount of the mixed particles is 0.3-0.5 g, the fixed spraying time is 7-10 s, the spraying distance is 5-6 mm, and the voltage is 15-20 KV.

[0016] Further, in step S4, the coating amount of the polydimethylsiloxane is 0.05-0.1 g.

[0017] Further, the wavelength of the UV lamp in step S4 is 365 nm, the intensity is 2.6 mW·cm -2 , the irradiation time is 2-3 h.

[0018] A light energy adsorbing material with a broad spectrum of absorption is prepared by the method for preparing a light energy adsorbing material with a broad spectrum of absorption.

[0019] The light energy adsorbing material with a broad spectrum of absorption is used as a base material for manufacturing a solar evaporator. BRIEF DESCRIPTION OF DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, for those skilled in the art, other drawings can also be obtained based on these drawings without any creative effort.

[0021] Figure 1 The preparation process of the Ti2O3 nanoparticles and the mixed particles in the present application is shown in the following figure:

[0022] Figure 2 The X-ray diffraction pattern of the prepared Ti2O3 nanoparticles is shown in (a) of the following figure, and the SEM image of the prepared Ti2O3 nanoparticles is shown in (b) of the following figure:

[0023] Figure 3 The morphology and microstructure of the natural agate vine are shown in the following figure:

[0024] Figure 4 The microstructure and macrostructure of the vine surface loaded with C nanoparticles are shown in (a) of the following figure, the microstructure and macrostructure of the vine surface loaded with Ti2O3 nanoparticles are shown in (b) of the following figure, the microstructure and macrostructure of the vine surface loaded with mixed nanoparticles are shown in (c) of the following figure, and the side view morphology of the array structure and the micro-nano structure on the array structure are shown in (d) of the following figure:

[0025] Figure 5 The absorbance of the vine surface of R-r, T-r, C-r and TC-r and the solar spectrum irradiance are shown in (a) of the following figure, the XPS measurement spectrum of R-r, TC-r and TCP-r is shown in (b) of the following figure, the FTIR spectrum of TC-r and TCP-r is shown in (c) of the following figure, the thermal conductivity of different biomass materials is shown in (d) of the following figure, the water contact angle of the original vine and the vine loaded with photothermal materials is shown in (e) of the following figure, and the capillary performance of the natural agate vine section along the growth direction is shown in (f) of the following figure:

[0026] Figure 6Fig. 1 shows the evaporation performance of the solar evaporator; where (a) is the mass of R-r, C-r, T-r, TC-r, TCP-r and pure water as a function of time when working under a solar irradiation; (b) is the evaporation enthalpy of pure water and the water of the evaporator in the dark; (c) is the evaporation enthalpy of pure water and the water of the evaporator under a solar irradiation; (d) is the comparison of the evaporation rate and the solar-thermal conversion efficiency of the evaporator and other carbon-based or biomass material evaporators under a solar irradiation; (e) is the temperature of the surface of R-r, C-r, T-r, TC-r, TCP-r under a solar irradiation and the corresponding infrared images, showing the temperature distribution at irradiation time of 0, 180, 360 and 540 s, respectively;

[0027] Figure 7 Fig. 2 shows the salt resistance performance of the solar evaporator; where (a) is the environmental humidity, temperature and solar power during the outdoor solar evaporation experiment; (b) is the evaporation rate of T-r, C-r and TCP-r at different daytime; (c) is the evaporation rate of TCp-r in pure water for 10 cycles under 1 solar irradiation, the inset shows the mass of the system as a function of time at the 1st and 10th cycles;

[0028] Figure 8 Fig. 2 shows the salt resistance performance of the solar evaporator; where (a) is the environmental humidity, temperature and solar power during the outdoor solar evaporation experiment; (b) is the evaporation rate of T-r, C-r and TCP-r at different daytime; (c) is the evaporation rate of TCp-r in pure water for 10 cycles under 1 solar irradiation, the inset shows the mass of the system as a function of time at the 1st and 10th cycles; DETAILED DESCRIPTION

[0029] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0030] Embodiment 1

[0031] A preparation method of a light energy adsorbing material with broad spectrum absorption, the preparation method comprising the following steps:

[0032] S1, putting commercial Ti2O3 powder into a ball mill to obtain nano-sized Ti2O3 particles; the particle size of the steel balls in the ball mill is 5 mm, the ball milling time is 24 h, the rotation speed is 400 r / min, and the resting time is 10 min.

[0033] S2, mixing the nano-sized Ti2O3 particles and the nano-sized carbon particles, adding anhydrous ethanol, stirring uniformly, and then drying in an oven to obtain mixed particles; the mass ratio of the nano-sized Ti2O3 particles to the nano-sized carbon particles is 3:1.

[0034] S3, adding polyvinyl alcohol into deionized water, heating to completely dissolve, and then cooling to room temperature to obtain a polyvinyl alcohol solution; uniformly coating the polyvinyl alcohol solution on the surface of the treated agate block; then spraying the mixed particles on the surface of the agate block; the concentration of the prepared polyvinyl alcohol solution is 0.8 g / ml; the diameter of the treated agate block is 20 mm; the thickness is 10 mm; the agate block needs to be polished with sandpaper before coating the polyvinyl alcohol solution; the coating amount of the polyvinyl alcohol solution is 0.05 g; the spraying amount of the mixed particles is 0.3 g; the fixed spraying time is 7 s, the spraying distance is 5 mm, and the voltage is 15 KV.

[0035] S4, coating polydimethylsiloxane on the surface of the agate block sprayed with the mixed particles, and irradiating with a UV lamp, and then taking out and drying in a drying box to obtain a hydrophobic surface; thereby obtaining a light energy adsorbing material with a broad spectrum of absorption. The coating amount of the polydimethylsiloxane is 0.05 g; the wavelength of the UV lamp is 365 nm, the intensity is 2.6 mW·cm -2 , and the irradiation time is 2 h.

[0036] Comparative Example 1

[0037] Comparative Example 1 and Example 1, a common commercial Ti2O3 powder is used, and the commercial Ti2O3 powder is not ball milled; the other steps are the same as those in Example 1, and a light energy adsorbing material with a broad spectrum of absorption is prepared.

[0038] Comparative Example 2

[0039] Comparative Example 2 and Example 1, in step S2, the nano-sized carbon particles are not mixed with the nano-sized Ti2O3 particles, i.e., the nano-sized carbon particle component is missing in step S2; the other steps are the same as those in Example 1, and a light energy adsorbing material with a broad spectrum of absorption is prepared.

[0040] The X-ray diffraction pattern of the ball-milled commercial Ti2O3 powder can be well indicated as corundum phase Figure 2 a). The representative scanning electron microscope (SEM) image of the prepared Ti2O3 nanoparticles shows that the average diameter is about 450 nm Figure 2 b);

[0041] The pore size of rattan is crucial for water transport. The image shows numerous tiny vertical channels running longitudinally. The diameter of the metaxylem vessels is approximately 300-350 μm; this relatively wide diameter ensures ample water supply. Slender proxylem vessels and sieve tubes surround the metaxylem vessels. Compared to the metaxylem vessels, these are narrower and smaller, typically 50-70 μm in diameter. This axial arrangement of slender vertical channels facilitates vertical water transport. Furthermore, numerous pits arranged on the cell walls serve as horizontal channels for salt exchange, typically 0.5-1.5 μm high and 3-5 μm wide.

[0042] Ti₂O₃ nanoparticles have high hydrophilicity, making them easier to disperse in PVA when sprayed onto rattan surfaces. This results in better and more uniform dispersion on the rattan surface. Nano-carbon, on the other hand, has weaker hydrophilicity than Ti₂O₃, and its dispersion on PVA-coated rattan surfaces is generally not as good. Figure 4 As shown in b, the surface formed by Ti2O3 nanoparticles is relatively smooth at the microscopic level. The addition of nano-carbon reduces the dispersion of Ti2O3 powder to some extent, making the coated surface rougher. During the cutting process, trace amounts of tissue remain around the vascular bundles, resulting in a uniform and dense array structure with a diameter of approximately 200 μm and a height of approximately 200 μm formed around the vascular bundles after the mixed powder is sprayed. Due to the increased roughness, numerous micro- and nano-clusters appear on the array surface. This micro- and nano-structure increases the light-absorbing area, reduces the surface reflectivity, and prolongs the residence time of sunlight inside the material, thereby enhancing the interaction between light and material and improving the photothermal conversion efficiency and absorbance. Figure 4 ).

[0043] Ti₂O₃, as a semiconductor with an extremely narrow bandgap, exhibits high photothermal conversion efficiency and higher absorbance than carbon in the ultraviolet and visible light bands. Tr (TiO₃) reaches 90.03% absorbance in the 500-2500 nm wavelength range. However, its absorbance in the near-infrared band shows a significant decreasing trend and is also much lower than that of Cr in the near-infrared band. Cr's absorbance reaches 93.12%. The synergistic effect of the uniform mixing of the two compensates for their respective deficiencies in different wavelength bands, and its absorbance in the near-infrared band does not show a significant decreasing trend. TC-r's absorbance reaches 95.92% (…). Figure 5 a). Furthermore, we used XPS to characterize the chemical composition of unprocessed rattan, rattan with attached mixed particles, and rattan with an attached hydrophobic layer. The Ti content of the rattan significantly increased after loading Ti₂O₃ nanoparticles, and the attachment of the hydrophobic layer increased the Si content to 10.15%, while the Ti content decreased to 5.82%. Figure 5b) The functional group changes of the original rattan, rattan with Ti2O3 nanoparticles and hydrophobic layer were characterized by FTIR. Ti-O-Ti bond appeared in both TC-r and TCP-r, and a large number of silicon-based functional groups appeared in TCP-r Figure 5 c) During the operation of the evaporator, the agate rattan has a lower thermal conductivity of 0.23 W·m -2 ·K -1 This makes it reduce the heat loss to the surrounding moisture during evaporation, while the thermal conductivity of the treated rattan only has a small amount of improvement, which is 0.26 W·m -2 ·K -1 and 0.28 W·m -2 ·K -1 , lower than the thermal conductivity of other biomass materials Figure 5 d) After hydrophobic treatment, the water contact angle of TC-r increases from 73.9° to 131.2°, which lays the foundation for its salt resistance, while the hydrophobic angle of T-r is only 54.8°, slightly higher than R-r. Due to the partial hydrophobicity of carbon particles, the hydrophobic angle of C-r reaches 70.9° Figure 5 e) The rapid water transport of agate rattan is due to its large capillary force. In the dyeing experiment, the red dye rises to the top of the half-round rattan with a thickness of 1 mm in only 3 seconds, and the flow rate is about 3.4 mm·s -1 , while the non-porous Chinese fir is only 0.5 mm·s -1 ( Figure 5 f)。

[0044] The mass change of the evaporator during operation often reflects the performance of the evaporator. By fitting the slope of the mass-time curve, the evaporation rate can be calculated. In general, the evaporation rate of R-r is 0.55 Kg·m -2 ·h -1 , the evaporation rates of T-r and C-r increase significantly, reaching 2.02 Kg·m -2 ·h -1 and 1.97 Kg·m -2 ·h -1 respectively. The evaporation rate of TC-r prepared by mixing the two powders in a certain proportion increases significantly on this basis, reaching 2.35 Kg·m -2 ·h -1 , and the evaporation rate of TCP-r prepared by hydrophobic treatment of TC-r increases slightly, reaching 2.39 Kg·m -2 ·h -1 ( Figure 6 a)。 Figure 6 b and Figure 6c shows the enthalpy of vaporization of pure water and a system consisting of an evaporator and water under dark conditions and under sunlight conditions, respectively (the names of the systems consisting of evaporators and water are hereinafter referred to as the abbreviations for the treated rattan). At room temperature, the enthalpy of vaporization of pure water is 2.44 MJ·kg⁻¹. -1 Rr is 1.90 MJ·kg -1 The enthalpy of vaporization of the treated rattan decreased, with Tr and Cr at 1.39 and 1.42 MJ·kg⁻¹, respectively. The enthalpy of vaporization of TC-r decreased slightly, reaching 1.30 MJ·kg⁻¹. -1 After coating with a hydrophobic layer, the enthalpy of evaporation did not change significantly, and TCP-r was 1.32 MJ·kg⁻¹. -1 Under sunlight, as temperature increases, the enthalpy of vaporization decreases further, with the enthalpies of vaporization for Tr and Cr decreasing to 1.37 and 1.39 MJ·kg⁻¹, respectively. -1 The enthalpy of vaporization of TC-r decreased to 1.27 MJ·kg⁻¹. -1 The enthalpy of vaporization of TCP-r decreased to 1.29 MJ·kg⁻¹. -1 The enthalpy of evaporation is closely related to the photothermal conversion efficiency, and they are usually related by the following equation:

[0045]

[0046] in The net evaporation rate, h, can be calculated based on the evaporation rate under sunlight and the evaporation rate in darkness. LV The enthalpy of phase change when a liquid transforms into a vapor, including sensible heat (h). sh ) and enthalpy of evaporation (h ee ),C opt P0 represents the optical concentration, where P0 is the solar radiation from one solar illumination. For example... Figure 6 As shown in Figure d, the final product TCP-r exhibited a photothermal conversion efficiency of 93.5%, which is comparable to the photothermal conversion efficiencies of other reported carbon-based or biomass evaporators, while its evaporation rate is also among the highest. Furthermore, under sunlight irradiation, the temperature of Rr slowly rose to 34.2℃ within 600s. Tr, TC-r, and TCP-r, due to the presence of semiconductor Ti2O3, experienced faster temperature increases, reaching quasi-steady states of approximately 43.8℃, 43.7℃, and 44.9℃ respectively at 540s. Cr stabilized at approximately 40.8℃ at 540s.

[0047] In practical applications, sunlight is not always perpendicular to the evaporator surface. Over time, the incident light angle changes from 0° at sunrise to 90° at noon and then back to 0° at sunset. For most of this period, the angle between the incident light and the evaporator is less than 90°. We conducted an outdoor evaporation experiment to study the evaporation performance of the evaporator in practical applications. The experiment was conducted on a typical sunny day in Nanjing, Jiangsu Province (24°32′N, 117°22′E). During this experiment, ambient humidity, temperature, and solar power were recorded hourly. Figure 7 a) The average solar flux measured outdoors was 0.62 kW·m. -2 The evaporation rate measured during this period was lower than that measured under ideal laboratory conditions; the evaporation rate of TCP-r was 0.92 kg·m³ at 6:00 AM. -2 ·h -1 At noon, it was 1.72 kg·m -2 ·h -1 From 12 noon to 3 pm, the evaporation rate remained at 1.70 kg·m³. -2 ·h -1 The concentration was above 1, and gradually decreased to 1.43 kg·m at 6 PM. -2 ·h -1 The evaporation rates of Tr and Cr remained at only 1.3 kg·m³ between 12:00 PM and 3:00 PM. -2 ·h -1 Around 12 o'clock, the evaporation rate of Tr reached 1.35 kg·m³. -2 ·h -1 The evaporation rate of Cr was only 1.3 kg·m³ at noon. -2 ·h -1 ( Figure 7 b) Furthermore, the average evaporation rate of TCP-r reached 1.53 kg·m³. -2 ·h -1 The average evaporation rate of Tr is 1.15 kg·m³. -2 ·h -1 The average evaporation rate of Cr is only 1.13 kg·m³. -2 ·h -1 The synergistic effect of the mixed particles allows TCP-r to maintain a relatively stable and high evaporation rate in practical applications. Figure 7 c shows the change in evaporation rate of the final product TCP-r during 10 cycles of evaporation experiments (each cycle includes 12 hours in darkness and 12 hours in sunlight). The inset shows the change in its mass over time during the 1st and 10th cycles, where the maximum difference in evaporation rate between individual cycles is only 3%, ensuring the stability of the evaporator under long-term operation.

[0048] In practical application, it is of vital importance to ensure the long-term salt tolerance of the evaporator. The excessive deposition of salt greatly reduces the light absorption capacity of the light absorption layer of the evaporator, and also blocks the duct, making it difficult for water to be replenished, resulting in a serious decline in the evaporation rate. The introduction of the hydrophobic layer greatly reduces the hydrophilic performance of the light absorption layer surface. After the salt is enriched on the surface of the hydrophobic layer, it is sent back to the bulk solution due to the driving force of the concentration gradient. In addition, the surface temperature of the evaporator is much higher than that of the bulk solution, which accelerates the redissolution of the salt. Figure 8 a shows the evaporation rate of TCP-r in different NaCl solutions. The evaporation rate of TCP-r in 3.5wt% and 10wt% NaCl solutions is stable at 2.02Kg·m -2 ·h -1 and 1.91Kg·m -2 ·h -1 respectively. When the concentration rises to 15wt%, the evaporation rate of TCP-r does not decrease significantly, and can still be maintained at 1.70Kg·m -2 ·h -1 The above, when the concentration further rises to 20wt%, the performance of the evaporator does not decrease significantly in the first four hours, and can still be maintained at 1.40Kg·m -2 ·h -1 or so. At the fourth hour, the salt begins to deposit. Due to the high concentration of the salt solution, the deposition rate begins to be higher than the dissolution rate. With the increase of the deposition area, the evaporation rate gradually decreases. At the 10th hour, the evaporation rate is only 0.78Kg·m -2 ·h -1 . As can be seen from the inserted figure, the light absorption surface of the evaporator is almost covered by the salt. After the evaporation test of various types of 10wt% salt solution, TCP-r can stably exert its evaporation performance, and among them, there is no obvious salt deposition. For 10wt% KCl solution, the evaporation rate of TCP-r can be stably maintained at 1.80Kg·m -2 ·h -1 or so. For 10.0wt% Na2SO4, it can also be stably maintained at 1.72Kg·m -2 ·h -1 or so. However, its evaporation rate in MgSO4 and CaCl2 is lower, about 1.66 and 1.58Kg·m -2 ·h -1 respectively. In simulated seawater, the evaporation rate of TCP-r is about 1.98Kg·m -2 ·h -1 Figure 8 b). In addition, we determined the ion concentration of the solution collected before and after the evaporation of TCP-r in various 10wt% salt solutions Figure 8 ​c), the ion concentration of distilled water collected from it was greatly reduced, which was far below the drinking water limits of the World Health Organization (WHO), the Chinese national standard (GBT) and the United States Environmental Protection Agency (EPA), and the desalination rate was more than 99%. In addition, in the comparative experiment, we continuously evaporated TC-r and TCP-r in simulated seawater for 5 days Figure 8 d), TC-r had more salt deposition on the third day, and on the fifth day, the salt almost covered the surface of the light-absorbing layer, while TCP-r still had no obvious crystallization phenomenon on the fifth day.

[0049] In the description of the present specification, the description referring to the terms "one embodiment", "an example", "a specific example" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0050] The basic principles, main features and advantages of the present application are shown and described above. It should be understood by those skilled in the art that the present application is not limited by the above embodiments, and the above embodiments and descriptions in the specification are only illustrative of the principles of the present application. Without departing from the spirit and scope of the present application, various changes and improvements can be made to the present application, and these changes and improvements all fall within the scope of the claimed present application.

Claims

1. A method for preparing a light energy adsorbing material having a broad spectrum of absorption, characterized in that, The preparation method comprises the following steps: S1, putting commercial Ti2O3 powder into a ball mill for ball milling to obtain nano-sized Ti2O3 particles; S2, mixing the nano-sized Ti2O3 particles and nano-sized carbon particles, adding anhydrous ethanol, stirring uniformly, and then drying in an oven to obtain mixed particles; the mass ratio of the nano-sized Ti2O3 particles to the nano-sized carbon particles is 3-5:1; S3, adding polyvinyl alcohol into deionized water, heating to completely dissolve the polyvinyl alcohol, and then cooling to room temperature to obtain a polyvinyl alcohol solution, uniformly coating the polyvinyl alcohol solution on the surface of the treated agate block, and then spraying the mixed particles on the surface of the agate block; S4, coating polydimethylsiloxane on the surface of the agate block on which the mixed particles are sprayed, irradiating with a UV lamp, and then taking out and drying in a drying box to obtain a hydrophobic surface.

2. The method for preparing a light energy adsorption material with broad-spectrum absorption according to claim 1, characterized in that, In step S1, the particle size of the steel balls in the ball mill is 5-10 mm, the ball milling time is 24 h, the rotating speed is 400 r / min, and the resting time is 10 min.

3. The method for preparing a light energy adsorption material with broad-spectrum absorption according to claim 1, characterized in that, In step S3, the concentration of the prepared polyvinyl alcohol solution is 0.8-1.5 g / ml.

4. The method for preparing a light energy adsorption material with broad-spectrum absorption according to claim 1, characterized in that, In step S3, the diameter of the treated agate block is 20 mm, the thickness is 10 mm, and the agate block needs to be polished with sandpaper before being coated with the polyvinyl alcohol solution.

5. The method for preparing a light energy adsorption material with broad-spectrum absorption according to claim 1, characterized in that, In step S3, the coating amount of the polyvinyl alcohol solution is 0.05-0.1 g, the spraying amount of the mixed particles is 0.3-0.5 g, the fixed spraying time is 7-10 s, the spraying distance is 5-6 mm, and the voltage is 15-20 KV.

6. The method of claim 1, wherein the light energy absorbing material having a broad spectrum of absorption is prepared by the steps of: In step S4, the coating amount of the polydimethylsiloxane is 0.05-0.1 g.

7. The method for preparing a light energy adsorption material with broad-spectrum absorption according to claim 1, characterized in that, The wavelength of the UV lamp in step S4 is 365 nm, the intensity is 2.6 mW·cm -2 , and the irradiation time is 2-3 h.

8. A light energy adsorbing material with broad spectrum absorption is prepared by the preparation method of the light energy adsorbing material with broad spectrum absorption according to any one of claims 1-7.

9. The light energy adsorbing material with broad spectrum absorption according to claim 8 is used as a base material for manufacturing a solar evaporator.

Images