The manufacturing advantages to 3D printing the water purification system lie in the design and function of the unit, as well as the nature of the semiconductor nanocrystals. Via 3D printing, the conically shaped tank, made out of a polymer with a melting point higher than 100C (like nylon or reinforced HDPE) can be easily manufactured with common extrusion printing techniques. The curved QD solar cell can then be printed onto the conical surface of the tank, using dispersant evaporation techniques analogous to those used in spin coating. This would allow for uniform layer by layer deposition and the ability to segment cells as needed. The fact that deposition of the CQD thin films doesn't rely on extremely hot melting temperatures allows the tank to be made out of relatively inexpensive polymers, compared to the glass substrates that are usually associated with solar cells. Possibly the most convincing advantage to 3D printing is the fact that it allows for manufacturing of the unit in the geographical location where it is needed. The manufacturing costs are equal to the cost of the 3D printer, and the manufacturing "plant" is located where needed.
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