Visible-light photoactivity of plasmonic silver supported on mesoporous TiO2 nanoparticles (Ag-MTN) for enhanced degradation of 2-chlorophenol: limitation of Ag-Ti interaction

Various weight loadings of Ag (1–10 wt.%) were introduced to mesoporous titania nanoparticles (MTN) via a direct in-situ electrochemical method. The catalysts were characterized by XRD, surface area analysis, FTIR, ESR, FESEM-EDX and TEM. Characterization results indicated that the introduction of A...

Full description

Saved in:
Bibliographic Details
Main Authors: Jaafar, N. F., Jalil, A. A., Triwahyono, S.
Format: Article
Published: Elsevier B.V. 2017
Subjects:
Online Access:http://eprints.utm.my/id/eprint/75353/
https://www.scopus.com/inward/record.uri?eid=2-s2.0-84989329143&doi=10.1016%2fj.apsusc.2016.09.112&partnerID=40&md5=58adb7eec036d0b3266668d61cd94c0a
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Various weight loadings of Ag (1–10 wt.%) were introduced to mesoporous titania nanoparticles (MTN) via a direct in-situ electrochemical method. The catalysts were characterized by XRD, surface area analysis, FTIR, ESR, FESEM-EDX and TEM. Characterization results indicated that the introduction of Ag onto MTN decreased the particles size and band gap of the MTN while increasing the number of oxygen vacancies (OV) and Ti3+ site defects (TSD). The activity performance of Ag-MTN on photodegradation of 2-chlorophenol (2-CP) under visible light irradiation was in the following order: 5 wt% Ag-MTN> 1 wt% Ag-MTN > MTN > 10 wt% Ag-MTN, with degradation percentages of 97, 88, 80 and 63%, respectively. The synergistic effect between Ag0 and MTN seemed to play an important role in the system. The Ag0 acted as both an electron trap and a plasmonic sensitizer which suppressed the electron-hole recombination, while OV and TSD in the MTN accelerated the production of hydroxyl radicals for enhanced degradation of 2-CP. However, the formation of Ti-O-Ag in 10 wt% Ag-MTN was found to decrease the photoactivity due to the decrease in the formation of Ag0, TSD and OV as well as the increase in band gap energy. The photodegradation of 5 wt% Ag-MTN followed a pseudo-first-order Langmuir- Hinshelwood model and the catalyst was still stable after five cycles.