Silver carbonate loaded on activated carbon composite photocatalyst with enhanced photocatalytic activity under visible light irradiation

Abstract

A composite photocatalyst based on silver carbonate (Ag₂CO₃) loaded on activated carbon (AC) was prepared by ion-exchange deposition method. The obtained photocatalyst was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), UV/Vis diffuse reflection spectroscopy (DRS), N₂ adsorption–desorption measurements and transient photocurrent measurements. The removal efficiency of Ag₂CO₃/AC composite including adsorption and photodegradation was studied for degrading Rhodamine B (RhB) in aqueous solution under visible light irradiation. Compared with the pure Ag₂CO₃, the prepared composite catalyst has larger surface area and adsorption capacity of organic pollutants. It could be summarized that synergy of photodegradation and adsorption has a great improvement for the removal of RhB under visible light irradiation compared with that of only adsorption without light. A remarkable RhB removal efficiency of 96.6% was achieved by the prepared Ag₂CO₃/AC (20%) composite. The possible catalytic reaction mechanism of Ag₂CO₃/AC was also proposed.

Keywords:

• Silver carbonate
• Active carbon
• Photodegradation
• Organic pollutant

Additional information

Funding

This project was supported by the Innovation Program for Graduate Education of Jiangsu Province [KYLX15_1041]; Natural Science of Jiangsu Province [BK20141298]; Society Development Fund of Zhenjiang [SH2013020].