Dear Halayit Abrha

For your question, have you analyze it by using FTIR or XPS to know the bonding interaction between them? I guess that some of ZnO particles anchored on the MP materials.

By the way, for the another perspective that maybe good for you, if you have some detail information about the melting or combustion point of MP, subsequently heating them through calcination process until the MP removed, thereby, you will get some insight to know the weight loss of degraded MP by suggested formula below. However, you should consider the ZnO structure stability while MP combustion take place.

W(degraded MP)= W(MP initial or total) - ((W(ZnO+MP) - W(ZnO after combustion)) + W(MP after degradation or MP final))

with W and MP are weight of catalyst and microplastic. Maybe that formula is confusing, but it is just a simple mathematics formula.

May it help you.

In my opinion, centrifugation is the best option as we do this normally when have to separate the nanoparticle from the solution (dye solution). Simple FTIR of ZnO before and after reaction can show the difference.

How you conduct the experiment, it would be helpful to analyze the full picture

Hi Halayit Abrha

You should use centrifugal insulation to remove material from solution. In my opinion that is the most effective way, besides, you can also try using external magnetic materials for magnetic materials.

For determining the amount of decomposed pigment, you need to establish a calibration curve of that pigment using UV-Vis measurement.

Quan-Doan Mai

@Halayit, I can suggest you that the nanoparticles size and surface area are very less compared to MPs. Hence, better to expand the ZnO surface area by dissolving in benign solvent and in which try degradation of MP, definitely you may get good results.