Electrical properties of samarium cobaltite nanoparticles synthesized using Sol–Gel autocombustion route

Highlights: • The structural evolution and its electrical properties of samarium cobaltite nanograins are discussed. • Optimization of SmCoO₃ nanograins is achieved by post sintering as-prepared gel at 800 °C. • The impedance spectra indicate the semiconducting behavior SmCoO₃ nanograins. - Abstract: Nanograins of SmCoO₃ are prepared by citric acid assisted Sol–Gel autocombustion route. The characterizations of crystal structure, surface morphology and electrical properties of SmCoO₃ powder are done using XRD, HRSEM, FTIR and BDS. The structural evolution of SmCoO₃ upon increasing the annealing temperature is followed using XRD and FTIR analyses. The powder sample contains polycrystalline grains with average size equal to 35 nm and orthorhombic perovskite structure with Pbnm space group. The vibrational bands observed in FTIR spectrum at 545 cm⁻¹ and 439 cm⁻¹ correspond to Co-O stretching modes in cobaltite system. HRSEM images of the sample show the formation of hexagonal shaped grains of samarium cobaltite. The AC electrical conductivity of 4.914 × 10⁻⁵ S cm⁻¹ at 295 K is measured for SmCoO₃ nanoparticles. The impedance spectra bring out the semiconducting behavior of the material