Hydrothermal synthesis of Cr-doped SrTiO3 nanoparticles for rhodamine-B dye degradation under visible light illumination

Highly crystalline Cr-doped SrTiO3 nanoparticles were effectively synthesized with strontium acetate, titanium isopropoxide, and chromium nitrate as precursors via citric acid-assisted hydrothermal process followed by calcinations. The synthesized Cr-SrTiO3 NPs possess monodispersity with average particle size diameter 50 ± 5 nm, leading to agglomeration of NPs which might create grain boundaries and oxygen vacancies in the crystal. Doping of Cr into SrTiO3 lattice tailored the electronic structure which extended its absorption into the visible region. The photocatalytic activity was successfully explored to demonstrate the facile degradation of rhodamine-B (RhB) dye under visible light illumination. The result shows the excellent degradation (~77%) of RhB dye in short time span of 120 min and degradation followed the first-order reaction kinetics with rate constant k = 0.0103 min−1.