PVD technology can deposit nano-thickness metal films and metal oxide films on the substrate. We can design and prepare composite coatings composed of materials of different thicknesses and different compositions in the nanometer scale to achieve selectivity to the solar spectrum. Precise control of absorption, transmission and reflection.

In the past 20 years, the chief creators of our company have cooperated with the German Solar Energy Research Institute to prepare cermet solar selective coatings for industrialized PVD and have achieved continuous success. The company has established strategic partnerships with the most influential German research institutes in the industry and the most powerful local equipment suppliers in China. The magnetron sputtering production line with high weather resistance and selective absorption coating developed by the company is a world-class independent innovation. The coating absorption zone adopts PVD selective coating technology and process, continuous production, stable quality and low cost. The solar absorption rate of the selective coating is 95%, the divergence rate is 5%, the heat conversion efficiency is high, the coating is corrosion-resistant, and the durability is long. At present, there is no such equipment in China. The equipment has a high degree of automation, high production efficiency of continuous coating, good product consistency, and low labor costs. We have the experience and ability to independently design, manufacture and integrate a large-scale domestic magnetron sputtering solar selective cermet coating production line with the same technological level as Germany. Of course, we have the know-how to design and prepare composite coatings made of materials with different thicknesses and different compositions in the nanometer scale to achieve the precise control of selective absorption, transmission and reflection of the solar spectrum.

For flat panel solar collector light-to-heat conversion coatings, there are currently 4 solutions: spraying, anodizing, black chrome plating, and magnetron sputtering (blue film).

Among them, the coating prepared by the spraying process is basically not selective, which means that the absorption ratio of the solar spectrum and the emission ratio of the infrared band are close or even equal. As a result, the coating is transparent and absorbing to both the solar spectrum band (0.3μm～2.5μm) and the infrared band (2.5μm～25μm). There will be heat absorption in the solar spectrum and heat dissipation through infrared radiation. Anodizing and electroplating black chromium have a certain selectivity and high infrared emission. Magnetron sputtering blue film has high selectivity and a large energy efficiency ratio α/ε.

The working principle of selective absorption coating is as follows:

The optical properties of several process coatings are compared as follows:

The comparison of weather resistance test of several magnetron sputtering blue film coatings at home and abroad is as follows:

BTE has the invention patent of highly weather-resistant selective absorption coating (blue film), and has obtained excellent optical performance in actual product application α=95% (@AM1.5), ε=5.8% (@80℃), and It has obtained weather resistance that exceeds that of similar foreign products, and can be used in complex process environments.