Low temperature synthesis of nanocrystalline scandia-stabilized zirconia by aqueous combustion method and its characterizations

Abstract

Zirconia stabilized with 11 mol% scandia (11ScSZ) has been successfully synthesized by novel alanine-assisted soft chemical aqueous combustion method. The reaction kinetics during combustion synthesis has been studied in detail by analysing thermal behaviour of different metal–alanine complexes. A single phase 11ScSZ powder is achieved at significantly low calcination temperature of 500∘C. Field emission scanning electron micrograph reveals an agglomerated morphology with particle size ranging from 80 to 100 nm. The thermal expansion coefficient is found to be 11.03 × 10−6 ∘C−1 in the temperature range between room temperature and 1000∘C. Optical bandgap of 5.19 eV has been determined using UV–Vis spectroscopy and results are compared with the help of theoretical density of states. The total electrical conductivity of sintered pellet is found to be 7.3 × 10−3 S cm−1 at 700∘C as measured by impedance spectroscopy.