Development of AgFeO2/rGO/TiO2 Ternary Composite Photocatalysts for Enhanced Photocatalytic Dye Decolorization

Nasir Shehzad,Woo Young Kim,Muhammad Zafar,Murid Hussain,Muhammad Ashfaq,Kshaf Azam,Nabeel Ahmad,Parveen Akhter,Ainy Hafeez,Abdul Razzaq

doi:10.3390/cryst10100923

Abstract

Dyestuff is one of the most widely released pollutants into the environment. Many approaches have been considered to deal with the dye removal from polluted water such as adsorption, ultrafiltration, osmosis, solvent extraction and photocatalytic degradation. The photocatalytic degradation process is one of the most beneficial, economical and environmentally friendly ways to degrade the organic pollutants from wastewater. In this study, an efficient ferrite-based photocatalyst, AgFeO2/rGO/TiO2 was successfully developed using simple deposition and reflux method. Physical, chemical and structural properties were analyzed by using XRD, FTIR Raman and PL spectroscopy. The efficiency of photocatalyst was investigated for the decolorization of methyl blue (MB) dye and activity was measured through UV-vis spectroscopy. The effect of parameters like pH, concentrations of MB dye, and loading of silver ferrite (AgFeO2) was investigated. The study depicted that the properties of TiO2 were improved due to addition of silver ferrite and reduced graphene oxide (rGO). The 2.5% AgFeO2/rGO/TiO2 exhibited the highest efficiency and completely degraded the 50 ppm of MB dye in 30 min. The parametric study revealed that dye decolorization is faster in a neutral solution than in basic and acidic medium. The higher performance of the photocatalyst was attributed to the reduced charge recombination and improved optical properties. Thus, AgFeO2/rGO/TiO2 can be a potential composite for photocatalytic dye degradation and other photocatalytic applications under UV-Visible light irradiations.

Highlights

Water pollution is one of the biggest threats to the ecological system
The chemicals required for the preparation of AgFeO2 /reduced graphene oxide (rGO)/TiO2 nanocomposite are graphite nano powder (≤20 μm, 99.90% Sigma Aldrich), potassium permanganate (≥99%, R&M chemicals), hydrogen peroxide H2 O2 (30%, Merck), absolute ethanol C2 H5 OH (99.99% Merck), sulphuric acid
The AgFeO2 /rGO/TiO2 composites are successfully prepared into two-step processes: (i) deposition; (ii) reflux method

Summary

Introduction

Water pollution is one of the biggest threats to the ecological system. Around 80% of the wastewater produced in the world is discharged into environment without proper treatment, polluting freshwater resources [1]. The industrial sector is one of the largest sources of water pollution, which releases toxic chemicals into local water bodies. Industrial wastewater treatment gets the least attention, . Crystals 2020, 10, 923 in developing countries, due to which around 70% of effluents go untreated [2]. Dyestuffs from textile and food industry are considered to be one of the crucial water pollutants. Dyes are complex organic compounds which are non-biodegradable in nature and have adverse health effects such as cancer, asthma, skin allergies, and respiratory diseases [3]

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Results

Conclusion