Production method of solar energy optical-thermal conversion material

Abstract

The invention discloses a production method of a solar photothermal conversion material. The solar photothermal conversion materials produced by the prior art have defects such as poor thermal stability, UV resistance, corrosion resistance, small lighting area, and inability to realize the integration of solar thermal utilization systems and building structures. The present invention adopts chromium alloy steel as the matrix, and then performs pretreatment on it; the pretreated chromium alloy steel is subjected to chemical polishing treatment; the polished chromium alloy steel is subjected to chemical oxidation and coloring treatment, and the used chemical coloring solution includes sulfuric acid, Nitrate, ammonium sulfate and hydroxybenzoic acid; the chromium alloy steel with a black conversion film on the surface obtained in the previous step is chemically sealed; the finished product is dried. The invention uses low chromium alloy steel for acidic chemical coloring to obtain a novel solar light-to-heat conversion material, is suitable for producing large-area solar light-to-heat conversion materials, and can realize the integration of solar heat utilization systems and building structures.

Description

technical field [0001] The invention relates to the field of preparation of solar energy absorbing coating materials, in particular to a production method of solar light-to-heat conversion materials. Background technique [0002] Solar energy is an inexhaustible renewable energy source for human beings, and it is also a clean energy source that does not produce any environmental pollution. In the 1950s, two major technological breakthroughs occurred in the field of solar energy utilization, and these two technological breakthroughs laid the technical foundation for solar energy utilization to enter the modern development period. One is that Bell Laboratories of the United States developed a 6% practical monocrystalline silicon battery in 1954, and the other is that in 1955, Israel Tabor proposed the concept and theoretical basis of selective absorption surface and developed it into a practical black nickel photothermal conversion material. Solar photothermal conversion mate...

AI Technical Summary

Problems solved by technology

Solar photothermal conversion materials have a great impact on the technical and economic performance of solar thermal utilization. In order to improve the efficiency of solar thermal utilization and reduce costs, solar science and technology workers in various countries attach great importance to the research and development of solar photothermal conversion materials, and have developed many options. Absorbing black coating photothermal conversion material: (1) Black chromium coating photothermal conversion material, the current electroplating black chromium process is used, the current density is high (15-200A / dm2), the conductivity of the solution is poor, and a large amount of electricity will be generated during electroplating Joule heat, requiring cooling and ventilation to maintain normal production

In addition, black chromium plating on non-copper parts requires pre-plating copper, then bright nickel plating, and finally black chrome plating; this technology is difficult to produce large-area solar light-to-heat conversion materials, and the cost is high and the pollution is serious

(2) Black nickel coating photothermal conversion material, the black nickel coating is very thin and has poor corrosion resistance. In order to improve the bonding force and corrosion resistance of the coating and the substrate, an intermediate coating (such as Ni, Cu, Cd ) or double-layer nickel coating, so the production cost is relatively high; the thermal stability of black nickel coating is poor, usually only suitable for low temperature solar thermal utilization

However, it is difficult to produce large-area solar photothermal conversion materials with this technology, and the technology is not mature enough, the technology is difficult to master, and the production cost is also high

(4) Paint-type PbS-coated light-to-heat conversion material, the coating is simple to prepare and has good optical properties, but the dendritic PbS will gradually oxidize into white PbSO4, thus losing the light-to-heat conversion function

At the same time, the anti-rust ability of PbS is also poor, and it is usually only suitable for low-temperature solar thermal utilization.

(5) transition metal composite oxide coating photothermal conversion material, this kind of coating type coating is easy to prepare, has better optical performance and lower cost, but the coating adhesion is poor and easy to peel off

Usually only suitable for low temperature solar thermal utilization

(6) The photothermal conversion material with stainless steel black film layer has excellent spectral selectivity, thermal stability and high temperature resistance, but it uses high concentration of chromic acid and sulfuric acid, which needs to be operated at high temperature, and there are production equipment requirements High, harsh production environment, serious pollution, difficult operation, unstable solution, difficult color control, etc.

(7) Vacuum coating photothermal conversion materials widely used in my country, using vacuum evaporation and magnetron sputtering technology to prepare selective absorption coating, the performance is very good, but the base material uses vacuum glass tubes, vacuum glass tubes are used in building structures There are difficulties, and the area to collect solar energy is small

[0003] In short, the solar photothermal conversion materials produced by the existing technology have defects such as poor thermal stability, UV resistance, corrosion resistance, small lighting area, and inability to realize the integration of solar thermal utilization systems and building structures.

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