Mangosteen pericarp extract mediated synthesis of Ag/TiO2 nanocomposite and its application on organic pollutant degradation by adsorption-photocatalytic activity

Abstract

Herein, Ag/TiO2 nanocomposite was synthesized via a green chemistry approach, which is an eco-friendly, simple, and cost-effective method involving mangosteen pericarp extract as a reducing agent. The as-prepared nanocomposites were characterized using X-ray powder diffraction (XRD), Fourier transformation infrared spectroscopy (FT-IR), UV-Vis spectrophotometer, Scanning electron microscopy (SEM), Energy dispersive X-ray spectroscopy (EDS), Transmission electron microscopy (TEM), Zeta potential measurement, and nitrogen (N2) adsorption-desorption analysis. The performance of Ag/TiO2 nanocomposite was examined by degradation of methylene blue (MB) dye as a model of organic pollutant. The dye degradation using the Ag/TiO2 nanocomposite containing 45 mM of Ag revealed the high MB degradation, which is 85.77 % after 30 min under dark condition. Furthermore, complete degradation of 96.76 % was achieved after 2 h under visible light irradiation. In contrast, bare TiO2 only achieved 41.45 % after 30 min dark and 2 h visible light irradiation. This increase in degradation efficiency can be attributed to the adsorption process and the enhanced light absorption resulting from the localized surface plasmon resonance (LSPR) effect of Ag. Therefore, the green-synthesized Ag/TiO2 nanocomposite has great potential as an integrated adsorbent photocatalyst materials for remediating organic pollutants in dye effluents.

Keywords

• Ag/TiO2 nanocomposite
• Green synthesis
• Mangosteen pericarp extract
• Organic pollutant degradation
• Adsorption-photocatalytic activity