Visible‐Light‐Enhanced Photocatalytic Activity of Totally Inorganic Halide‐Based Perovskite

The removal of contaminants is an interesting topic in environmental research and for society nowadays. In this sense, perovskite materials have proven to be amazing photocatalysts. In this study, CsSnBr3 perovskite was synthesized and characterized using techniques such as x‐ray diffraction, Raman spectroscopy, x‐ray photoelectron spectroscopy and UV‐vis spectroscopy. A mixture of cubic and tetragonal crystalline phases was found in the sample, and XPS revealed the presence of two oxidation states for Sn, and the formation of surface non‐stoichiometric tin oxide. A good light harvesting in the visible range of the electromagnetic spectrum was also found for the perovskite synthesized, which is also insoluble in water. Furthermore, adsorption and photocatalytic tests were performed. Degradation of crystal violet dye was found after the adsorption tests, but the adsorption rate affected the photocatalytic process. Therefore, CsSnBr3 shows a good photocatalytic activity for degrading dyes and contaminants. CsSnBr3 perovskite synthesized shows enhanced photocatalytic activity under visible light. The highest photodegradation value reached 73.1%. The surface adsorption takes an important role in the degradation process, and it affects to the kinetics.