Spray coated of newly La-doped SnS₂ thin films for photocatalytic degradation application

In the present study, we present a comprehensive investigation on the synthesis and thorough characterization of La (2 and 4 at. %)-doped 2D-SnS₂ thin films, which were prepared by a spray-coating method with a clear molecular ink. These thin films were specifically targeted for their potential application in photodegradation. The impact of La doping on the structural, morphological, mechanical, and electrical properties of the thin films was analyzed using a range of appropriate techniques. Additionally, the mechanical properties were assessed through Vickers micro-indentation. The results indicate that the pristine SnS₂ films predominantly exhibit a preferred (101) crystal planes, while the introduction of La doping results in the appearance of a secondary Sn₂S₃ phase. The bandgap of the films was measured to range from 2 eV to 2.22 eV. Moreover, the thermoelectric power analysis revealed that the films exhibit n-type characteristics, and the mechanical properties showed an increase in hardness with La doping. Notably, the photocatalytic degradation rate was found to be 58.2%, 60.27%, and 62.92% for pristine SnS₂, La (2 at.%)-SnS₂, and La (4 at.%)-SnS₂, respectively, when tested against Malachite green dyes under visible light. This enhancement in degradation efficiency can be attributed to the presence of La³⁺ ions, which promote electron-hole pair generation.