Coating Mechanism of AuNPs onto Sepiolite by Experimental Research and MD Simulation

Coatings

Deniz Karataş¹  Ilgin Kursun Unver²  Dilek Senol Arslan²  Orhan Ozdemir² 

[1] Mineral Processing Engineering Department, Istanbul Technical University, Maslak, 34469 Istanbul, Turkey;Mining Engineering Department, Istanbul University-Cerrahpasa, Avcılar, 34320 Istanbul, Turkey;

关键词: gold nanoparticles;    aunps;    sepiolite;    zeta potential;    coating;    molecular dynamics simulation;    coulomb and van der waals interactions;    h-bonds;   

DOI  :  10.3390/coatings9120785

来源: DOAJ

【 摘 要 】

The amenability of gold nanoparticles (AuNPs) coating on natural and modified (hexadecyl trimethyl ammonium bromide, CTAB) sepiolite surfaces was studied both experimentally and theoretically. The zeta potential experiments and Fourier transform infrared spectrophotometer (FTIR), environmental scanning electron microscope (ESEM), and transmission electron microscopy (TEM) analyses were carried out with the sepiolite samples in the presence of AuNPs. In addition, the adsorption of three gold-nanoparticles on the sepiolite surface (100) in the absence and presence of CTAB was investigated by molecular dynamics (MD) simulations. The AuNPs showed no significant change in the zeta potential of natural sepiolite surfaces due to negative charges of both the sepiolite and AuNPs at natural pH. The surface charge of modified sepiolite decreased with the increase in AuNPs concentration indicating the significance AuNPs adsorption. FTIR, ESEM, and TEM analyses indicated the coating of AuNPs onto the modified sepiolite surface were higher than that of the natural sepiolite surface. The MD simulation results showed that AuNPs can easily adsorb onto the basal surface of the sepiolite due to its hydrophilicity in the presence and absence of CTAB as indicated in the experimental studies. In short, the modification of sepiolite with CTAB made the charge positive, and in turn considerably increased the AuNPs coating on sepiolite surfaces due to electrostatic attraction.

【 授权许可】

Unknown