Synthesis of palygorskite supported spherical ZnS nanocomposites with enhanced photocatalytic activity

Abstract

In this paper, palygorskite (Pal) and spherical zinc sulfide (ZnS) nanopowders were successfully synthesized by using a simple hydrothermal method. The ZnS nanoparticles were supported on the framework of Pal without agglomeration, thereby increasing the specific surface area of Pal/ZnS nanocomposites (from 36.33 m² g⁻¹ to 83.85 m² g⁻¹). The acquired nanocomposites exhibited a significant enhancement in photoactivity for the degradation of rhodamine B under simulated sunlight irradiation. Specifically, when the content of Pal was 40%, the nanocomposite showed optimal photocatalytic activity, with a degradation rate of rhodamine B of 100% in 150 min. The improved photocatalytic performance of the nanocomposites may be attributed to the fact that the incorporation of Pal not only strengthened the adsorption of rhodamine B, but also reduced the band gap energy of the nanocomposites and the recombination rate of electrons and holes. Such inexpensive high-performance Pal/ZnS nanocomposites could find potential applications for the degradation of organic dyes.