LaFe_(1-x)Mg_xO_3 Ultrafine Powders Synthesized by Solution Combustion and Its Photocatalytic Performances

Mg2+ doped La Fe O3 ultrafine powders were synthesized by solution combustion method. Effects of Mg2+ doping content on phase composition, microstructure and photocatalytic performances of the synthesized powders were investigated by XRD, SEM, BET, and UV-Vis. The results show that Mg2+ substitutes for Fe3+ to form La Fe1-xMgxO3(0≤x≤0.2) limited solid solution. When Mg2+ doping content is 0.1, La Fe0.9Mg0.1O3 powder has a maximum specific surface area(43.46 m2/g) and smaller particle size(100 nm and 150 nm in diameter and length direction, respectively). It has the best photocatalytic ability with photodegradation efficiency of 75.2% to methyl orange(10 mg/L) under high-pressure mercury lamp irradiation for 180 min. It increases 26.5% than that of the pure LaF eO 3 under the same experimental conditions, and the reaction may be described as the pseudo first order kinetics equation.