Ease synthesis of mesoporous WO3-TiO2 nanocomposites with enhanced photocatalytic performance for photodegradation of herbicide imazapyr under visible light and UV illumination

Adel A Ismail; Ibrahim Abdelfattah; Ahmed Helal; S A Al-Sayari; L Robben; D W Bahnemann

doi:10.1016/j.jhazmat.2015.12.041

Ease synthesis of mesoporous WO3-TiO2 nanocomposites with enhanced photocatalytic performance for photodegradation of herbicide imazapyr under visible light and UV illumination

J Hazard Mater. 2016 Apr 15:307:43-54. doi: 10.1016/j.jhazmat.2015.12.041. Epub 2015 Dec 28.

Authors

Adel A Ismail¹, Ibrahim Abdelfattah², Ahmed Helal³, S A Al-Sayari⁴, L Robben⁵, D W Bahnemann⁶

Affiliations

¹ Advanced Materials Department, Central Metallurgical R& D Institute, CMRDI, P.O. Box 87, Helwan 11421 Cairo, Egypt; Advanced Materials and Nano Research Center, Najran University, P.O. Box 1988, Najran 11001, Saudi Arabia. Electronic address: adelali141@yahoo.com.
² Water Pollution Research Dept., National Research Centre, 33 EL Bohouth St. (Former EL Tahrir St.), P.O. 12622, Dokki, Giza, Egypt.
³ Advanced Materials Department, Central Metallurgical R& D Institute, CMRDI, P.O. Box 87, Helwan 11421 Cairo, Egypt.
⁴ Advanced Materials and Nano Research Center, Najran University, P.O. Box 1988, Najran 11001, Saudi Arabia.
⁵ Chemische Kristallographie fester Stoffe, Universität Bremen, Germany.
⁶ Institut für Technische Chemie, Leibniz Universität Hannover, Callinstrasse 3, 30167 Hannover, Germany.

PMID: 26775101
DOI: 10.1016/j.jhazmat.2015.12.041

Abstract

Herein, we report the ease synthesis of mesoporous WO3-TiO2 nanocomposites at different WO3 contents (0-5wt%) together with their photocatalytic performance for the degradation of the imazapyr herbicide under visible light and UV illumination. XRD and Raman spectra indicated that the highly crystalline anatase TiO2 phase and monoclinic and triclinic of WO3 were formed. The mesoporous TiO2 exhibits large pore volumes of 0.267cm(3)g-1 and high surface areas of 180m(2)g(-1) but they become reduced to 0.221cm(3)g(-1) and 113m(2)g(-1), respectively upon WO3 incorporation, with tunable mesopore diameter in the range of 5-6.5nm. TEM images show WO3-TiO2 nanocomposites are quite uniform with 10-15nm of TiO2 and 5-10nm of WO3 sizes. Under UV illumination, the overall photocatalytic efficiency of the 3% WO3-TiO2 nanocomposite is 3.5 and 6.6 times higher than that of mesoporous TiO2 and commercial UV-100 photocatalyst, respectively. The 3% WO3-TiO2 nanocomposite is considered to be the optimum photocatalyst which is able to degrade completely (100% conversion) of imazapyr herbicide along 120min with high photonic efficiency ∼8%. While under visible light illumination, the 0.5% WO3-TiO2 nanocomposite is the optimum photocatalyst which achieves 46% photocatalytic efficiency.

Keywords: Imazapyr; Mesoporous; Photocatalyst; UV and visible light illumination; WO(3)–TiO(2).