Effect of Multiply Twinned Ag(0) Nanoparticles on Photocatalytic Properties of TiO2 Nanosheets and TiO2 Nanostructured Thin Films

Abstract

Ag-decorated TiO2 nanostructured materials are promising photocatalysts. We used non-standard cryo-lyophilization and ArF laser ablation methods to produce TiO2 nanosheets and TiO2 nanostructured thin films decorated with Ag nanoparticles. Both methods have a common advantage in that they provide a single multiply twinned Ag(0) characterized by {111} twin boundaries. Advanced microscopy techniques and electron diffraction patterns revealed the formation of multiply twinned Ag(0) structures at elevated temperatures (500 °C and 800 °C). The photocatalytic activity was demonstrated by the efficient degradation of 4-chlorophenol and Total Organic Carbon removal using Ag-TiO2 nanosheets, because the multiply twinned Ag(0) served as an immobilized photocatalytically active center. Ag-TiO2 nanostructured thin films decorated with multiply twinned Ag(0) achieved improved photoelectrochemical water splitting due to the additional induction of a plasmonic effect. The photocatalytic properties of TiO2 nanosheets and TiO2 nanostructured thin films were correlated with the presence of defect-twinned structures formed from Ag(0) nanoparticles with a narrow size distribution, tuned to between 10 and 20 nm. This work opens up new possibilities for understanding the defects generated in Ag-TiO2 nanostructured materials and paves the way for connecting their morphology with their photocatalytic activity.

Ag-Containing Carbon Nanocomposites: Physico-Chemical Properties and Antimicrobial Activity

“…In addition, all composites contain nanoparticles consisting of multiple fused nanoparticles with twin planes {111} with diameters up to 18 nm. The most common is the pentagonal fusion (fivefold twinned) with the common axis of the zone (110) (Figure 4f) [44]. The formation of such NPs may be a consequence of Ag agglomeration due to the accumulation of smaller spherical NPs during heat treatment.…”

Combination of alkali treatment and Ag3PO4 loading effectively improves the photocatalytic activity of TiO2 nanoflowers

“…18–20 Among them, the morphological structure design has been proved to be an effective strategy to enhance the photoabsorption capacity and photogenerated charge separation efficiency, thereby improving the photocatalytic performance of TiO 2 -based photocatalytic materials. 21–23 For example, Cheng et al prepared gold-loaded black TiO 2 nanotubes by in situ electrochemical reduction, and the synthesized material showed excellent photocatalytic performance, with 82% of RhB being degraded within 60 min. 24 Zhou et al prepared CuS nanoparticle-modified TiO 2 nanospheres by a hydrothermal method, and the three-dimensional TiO 2 @CuS catalyst provided more active sites for photocatalysis, thereby significantly improving the photocatalytic performance.…”