Facile-controllable synthesis of SnS2 with sulfur vacancy for boosted Cr(VI) photoreduction performance

Abstract

Intrinsic defect engineering is a powerful tool to tune electronic structures for achieving higher photocatalytic activity. Nevertheless, a more industrialized and controlled defect-engineering approach other than the current complex synthesized route is urgently needed. Herein, a facile and controllable hydrothermal strategy is applied to prepare self-defective SnS2 with the tunable sulfur vacancy and used to remove Cr(VI) for the first time. By various characterization tools, we systematically analyzed the structure of defective catalysts and uncovered the relationship between sulfur vacancy and photocatalytic activity. The results showed that the concentration of sulfur vacancy can be varied by adjusting the dosage of thioacetamide(TAA). Batch photocatalytic experiments also demonstrated that the photocatalytic ability for Cr(VI) on defective SnS2 materials partly exhibits a vacancy-dependent phenomenon. Especially, the SnS2 nanosheets with an optimal amount of sulfur vacancies exhibit superior photoreduction rate of Cr(VI) (100% in 20 min), roughly 18.09 times than that of pure SnS2, indicating that it possesses huge prospects for photocatalytic wastewater treatment. In perspective, our work paves a facile and controlled intrinsic defect route to optimize the performance of 2D photocatalysts and also opens a fundamental window toward other novel photocatalysts.