High Photocatalytic Performance of PSII–rGO Composite Towards Methylene Orange Degradation

Abstract

A PSII–rGO nanocomposite photocatalyst utilizing graphene oxide and PSII precursor was prepared in this study. In this proposed facile approach, PSII dimers were uniformly distributed on the reduced graphene oxide (rGO) sheets. The retained oxygen functional groups (OFGs) on rGO planes played a significant role in anchoring the PSII dimers. The samples were thoroughly characterized by X-ray diffraction (XRD), Raman spectroscopy, ultraviolet-visible (UVvis) spectroscopy, and photoluminescence spectra (PL) analysis. The photocatalytic activity of PSII–rGO composites was further investigated by photodegrading methyl orange (MO). As a result, the prepared PSII–rGO photocatalyst exhibited a high absorptivity towards MO and efficient charge separation properties. The efficiency of the PSII–rGO composites (61%) towards the degradation of MO was significantly higher compared to pure PSII (25%), showing a 36% increase within 5 h under visible light. Finally, the corresponding mechanism of this enhancement was proposed and discussed in detail. After receiving photoelectrons from PSII, the rGO plane effectively transferred them to pollutants, thereby achieving a high photocatalytic degradation efficiency. The introduction of rGO improved the photocatalysis and sensing properties of PSII by facilitating rapid electron/charge division. Overall, the prepared PSII–rGO nanocomposite shows great potential for practical applications.