N.F. Jaafar, A.A. Jalil, S. Triwahyono, J. Efendi, R.R. Mukti, R. Jusoh, N.W.C. Jusoh, A.H. Karim, N.F.M. Salleh, V. Suendo
Metallic Ag nanoparticles (Ag 0 ) were successfully activated using a direct in situ electrochemical method before being supported on TiO 2 . Catalytic testing showed that 5 wt% Ag-TiO 2 gave the highest photodegradation (94%) of 50 mg L -1 2-chlorophenol (2-CP) at pH 5 using 0.375 g L -1 catalyst within 6 h, while under similar conditions, 1 wt% and 10 wt% Ag-TiO 2 only gave 75% and 78% degradation, respectively. Characterization results illustrated that the photoactivity was affected by the amount of Ag 0 and oxygen vacancies which act as an electrons trap to enhance the electron-hole separation. While, the AgOTi bonds formation reduced the photoactivity. The degradation followed a pseudo-first order Langmuir-Hinshelwood model where adsorption was the controlling step. Study on the effect of scavengers showed that the hole (H + ) and hydroxyl radical (OH) play important roles in the photodegradation. The regenerated photocatalyst was still stable after five cycling runs. © 2015 Elsevier B.V. All rights reserved.
Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia, Johor Bahru, Johor, 81310, Malaysia; Institute of Hydrogen Economy, Universiti Teknologi Malaysia, Johor Bahru, Johor, 81310, Malaysia; Department of Chemical Engineering, Faculty of Chemical Engineering, Universiti Teknologi Malaysia, Johor Bahru, Johor, 81310, Malaysia; Ibnu Sina Institute for Fundamental Science Studies, Universiti Teknologi Malaysia, Johor Bahru, Johor, 81310, Malaysia; Department of Chemistry, Universitas Negeri Padang, Jl. Prof. Hamka Air Tawar, Padang, West-Sumatera, Indonesia; Division of Inorganic and Physical Chemistry, Faculty of Mathematics and Natural Science, Institut Teknologi Bandung, Jl Ganesha No. 10, Bandung, 40132, Indonesia
