Synthesis of highly porous LaCoO3 catalyst by Nanocasting and its performance for oxygen reduction and evolution reactions in alkaline solution

Highly porous LaCoO 3 perovskite was synthesized by a nanocasting method using a mesoporous silica template and subsequently applied as a bifunctional catalyst for the oxygen reduction and evolution reactions in alkaline solution. The La-Co citrate complex was mixed a porous SBA-15 silica template, and then, calcinated at 650 °C to prepare a LaCoO 3 /SBA-15 composite. Highly porous LaCoO 3 was prepared by treating this composite with NaOH to remove the SBA-15 silica template. The obtained LaCoO 3 showed a very rough surface, high surface area, and relatively small particle size compared with LaCoO 3 prepared by the sol-gel method. The catalytic performance of the highly porous LaCoO 3 for the oxygen reduction and evolution reactions was electrochemically measured in alkaline solution. LaCoO 3 prepared by the nanocasting exhibited higher cell performance than that prepared by sol-gel method due to its larger surface area.