Ag-loaded ZnO materials for photocatalytic water treatment

Effect of Silver Dopants on the ZnO Thin Films Prepared by a Radio Frequency Magnetron Co-Sputtering System

“…The peak of the Ag 3d 5/2 shifted from 367.5 eV for the Ag-ZnO (3%) co-sputtered film to 368.1 eV for the Ag-ZnO (5%) co-sputtered film. Such an asymmetric peak could be deconvoluted into two peaks at about 367.4 and 368.2 eV, which were, in turn, ascribed to the bonds associated with the metallic and ionic Ag (denoted as Ag 0 and Ag-O in the figure), respectively [ 21 , 40 , 42 , 43 ]. Clearly, the Al-ZnO (3%) co-sputtered film mainly contained the Ag-O chemical bond, whereas the metallic Ag-Ag bond dominated over the Ag-ZnO (5%) co-sputtered film.…”

Noble metal nanoparticles supported onto semiconducting oxides as catalysts for reduction reactions

“…Tafel slopes normally increase on materials with lower Pt contents, which indicates that the mechanism tends to involve a 2-electron reaction. This was also observed for our materials when compared to the commercial Pt/C.53 According to Shinagawa et al 52, the mechanism of the ORR is based on three different surface covering species, which are responsible for the slopes on the Tafel plot. At lower overpotentials, the theoretical slopes can vary from 40 to 120 mV dec-1 depending on the adsorbed species contributing to the rate determining step.…”

“…50,51 Mainly three methods are employed for these syntheses, the first is by soaking the preformed oxide with a precursor solution followed by reduction with the desired reducing agent. 52,53 The second method is by performing the synthesis of NPs in the presence of the oxide, so the particles nucleate and grow on top of the support.54-56 And the last method is the impregnation of preformed NPs onto the preformed oxide, both functionalized and not.57,58 The core-shell synthesis usually employs preformed metallic nanostructures and grows the oxide onto their surface or vice-versa.59,60 Their properties frequently change by varying the core shape, size, shell shape, and size.48 The most explored combinations are TiO2 and plasmonic metals due to the photocatalytic properties of this oxide.61,62 Janus particles, on the other hand, require complex syntheses and fine control, since a complex morphology is needed to achieve the required functionality. 63 Au NPs are widely employed metallic nanostructures since they provide LSPR to the hybrid material.…”

Magnetic Nanoparticles for Photocatalytic Ozonation of Organic Pollutants

“…Although the introduction of Ag in FeO particles reduced the BET surface area, this sample had the highest OMA removal rate, suggesting that the addition of Ag leads to an increase in activity. Sampaio et al [27] also observed increased efficiency in phenol degradation in the presence of ZnO loaded with Ag. The authors suggested that there is an optimal amount of Ag to generate an adequate quantity of holes and electrons, and an increase in the Ag load may lead to a surplus charge separation, which is not efficiently contributing to the reaction.…”