One-pot synthesis of cellulose/MoS2 composite for efficient visible-light photocatalytic reduction of Cr(VI)

Abstract

An effective cellulose/MoS2 (Ce/MoS2) composite was synthesized via a one-pot microwave-assisted ionic liquid method for the photocatalytic reduction of toxic Cr(VI). Effects of ionic liquids (ILs) on the MoS2 nanostructure were considered, and the obtained composite was characterized by x-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectrometry (XPS), and electrochemical impedance spectroscopy (EIS). The results indicated that the MoS2 nanoplates were anchored and dispersed on the surface of the cellulose. Compared with the pristine MoS2, the support of the cellulose greatly enhanced the photocatalytic reduction efficiency of Cr(VI) ions in solution, from 65.9% to nearly 100%. The reduction mechanism was considered, and the results implied that the simultaneous reduction of Cr(VI) during the initial dark adsorption process was observed due to the effect of citric acid as a hole scavenger. Finally, regeneration tests revealed that the Ce/MoS2 composite could be recycled and reused.