Surface modification of highly porous 3D networks via atmospheric plasma treatment

Abstract

Tetrapodal ZnO (T‐ZnO) and aerographite networks represent two highly open porous (94.6 and 99.96%, respectively) model materials on which the impact of an atmospheric‐pressure plasma was studied for the first time. The air plasma treatment by a surface barrier discharge caused remarkable surface modifications on the T‐ZnO template, leading to a large number of oxygen vacancies. These observations were made using scanning electron microscopy (SEM) and Raman spectroscopy. In the second proposed set‐up, pellets of aerographite material were processed to a plasma jet with pressurized air and nitrogen. Hexamethyldisiloxane (HMDSO) was introduced as a precursor into the effluent jet for nanoparticle deposition. Opposing trends in atomic concentrations versus distance to the plasma source were observed when the gas (nitrogen or pressurized air) was changed. More pronounced nanoparticle coverage occurred in the pressurized air plasma. Their distribution was studied using SEM, energy‐dispersive X‐ray (EDX), and Raman spectroscopy. Because of the higher oxidation in the pressurized air plasma treatment, the deposited nanostructures appeared to be a mixture of Si and SiOx nanoparticles.