Scalable low temperature in air solid phase synthesis of porous flower-like hierarchical nanostructure SnS2 with superior performance in the adsorption and photocatalytic reduction of aqueous Cr(VI)

Abstract

Abstract Nanosheets-constructed porous flower-like hierarchical nanostructure SnS 2 (which was labeled as F-SnS 2 ) was synthesized by heating the mixture of SnCl 2 ·2H 2 O and thiourea in air at 170 °C for 2 h, in combination with a subsequent washing with water. F-SnS 2 exhibited much more adsorption and faster visible-light (wavelength >420 nm)-irradiated photocatalytic reduction of aqueous Cr(VI), as compared with SnS 2 nanoparticles, nanoplates-assembled flowerlike hierarchical structure SnS 2 synthesized by hydrothermal method, Fe, N and C tri-doped TiO 2 , and hydrothermally treated g-C 3 N 4 . The underlying reasons for the far superior performance of F-SnS 2 were proposed, based on the comparison of the microstructure, specific surface area, optical, electrochemical impedance, photocurrent, surface charge, and Cr(VI) adsorption properties of F-SnS 2 and SnS 2 nanoparticles. Besides, the photocatalytic reusability and stability of F-SnS 2 , as well as the effects of photocatalytic testing parameters (including dosage of photocatalyst, initial pH and concentration of K 2 Cr 2 O 7 aqueous solution) on the Cr(VI) removal efficiency by F-SnS 2 were also studied. This work may advance our knowledge on the scalable low temperature solid phase synthesis of SnS 2 nanomaterial, and contribute to the application of SnS 2 in treating the Cr(VI)-polluted water.