Effect of Size Tuning of Hexagonal SnS₂ Nanosheet on the Efficiency of Photocatalytic Degradation Processes

Abstract Recent research on SnS₂ materials aims to enhance their photocatalytic efficiency for water pollution remediation through doping and constructing heterojunctions. These methods face challenges in cost‐effectiveness and practical scalability. This study synthesizes hexagonal SnS₂ nanosheets of various sizes via a hydrothermal method, assessing their performance in degrading methyl orange (MO) and reducing hexavalent chromium (Cr(VI)). The results show that smaller SnS₂ nanosheets exhibit higher photocatalytic efficiency under sunlight. Specifically, 50 mg of small‐sized nanosheets degraded 100 ml of MO (10 mgL⁻¹) in 30 min and reduced Cr(VI) (10 mgL⁻¹) in 105 min. The enhanced performance is attributed to: i) an energy bandgap of 2.17 eV suitable for visible light, and ii) more surface sulfur (S) vacancies in smaller nanosheets, which create electronic states near the Fermi level, reducing electron‐hole recombination. This study offers a straightforward strategy for improving 2D materials like SnS₂.