The role of synthesis methods on the structural, optical and photocatalytic response of CaTiO3: A comparative study

Perovskite CaTiO3 stands out as a strong candidate due to its diverse properties and applicability in vast areas of interest. This study highlights the structural and optical investigations in CaTiO3 perovskite nanoparticles synthesized through non-ceramic routes -Hydrothermal and Sol-gel methods. The structural characteristics were analysed using X-Ray Diffraction (XRD) and Fourier Transform Infrared (FTIR) spectroscopy. XRD patterns confirmed the orthorhombic crystal structure of CaTiO3 in both samples, with particle sizes of 22.6 nm for the hydrothermal method and 17.6 nm for the sol-gel method. Williamson-Hall analysis further supported these findings. FTIR spectra revealed the presence of metal oxide bonds corresponding to CaTiO3, confirming the formation of the material. Scanning Electron Microscopy (SEM) and Energy Dispersive X-Ray Analysis (EDAX) were carried out to examine the morphology and elemental composition of the samples. Optical properties were evaluated through Diffuse Reflectance Spectroscopy (DRS), with band gaps estimated as 3.67 and 3.83 eV for hydrothermal and sol-gel synthesized samples, respectively. Additionally, the photocatalytic activity of the synthesized nanoparticles was assessed against the methylene blue dye, with degradation kinetics analysed using the Langmuir-Hinshelwood model.