Dear H. Lamsaf:

There are several techinques to vary the reflected, absorbed, emitted, etc wavelenght of a surface using nanoscience and nanotechnology.

One on these is utilizing nanostructures called photonic crystals.

Another very common technique is to grow nanoparticles of a given material on a a matrix, then with the variation of the size of these nps you will be able to control the reflected wavelenght of light.

Another technique are the use of the so called QDs (Quantum Dots) which re-emit certain wavelenghs depending of the electrical and optical properties of the given material and on the absorbed light.

Also, you could design a coating with particles embedded in it , particles from materials which show phenomena as cathodoluminescence,

Electroluminescence or phosphorescence

Also using the physics of semiconductors and recombination proceses between a two semiconductor materials ... a p-n junction. (like a LED, a device that emits light)

There are several methods, Regards ! :)

Why not , more than method was used to change the color of coating especially used in color of car and also advanced method used powder or liquid of nanotechnology .

Franklin Uriel Parás Hernández thank you very much for your reply. Please do you have some references?

Regards

Saad Kariem Shather hello.. thank you for your reply. but I am talking about caoting with metals. Please could you send me some references?

Regards

Hi dear Lamsaf

I think It's possible

NANOTECHNOLOGY CAN ALTER THE COLOR OR SHAPE OR COATINGS. IT IS VERY USEFUL TODAY

https://patents.google.com/patent/US9482798

Please see this attached patent file. It might be useful for you.

Dear Dr.H. Lamsaf:

Greeting,

You know some of coating processes for plastic which is used in automobile done by electrochemical process using nickel , chromium metals.

best wishes