Synthesis of nano-particle and highly porous conducting perovskites from simple in situ sol-gel derived carbon templating process

Nano-sized La_0.6Sr_0.4Co_0.2Fe _0.8O_3-d (LSCF) and La_0.8Sr _0.2MnO_3-d (LSM) oxides were synthesized by a simple in situ sol-gel derived carbon templating process. Nano-sized LSCF-carbon and LSM-carbon composites were first obtained with a grain size of 20-30 nm. Further calcination of the obtained composites under air resulted in the nano-sized pure-phase perovskites with crystalline size of as small as 14 nm. Such a decrease in crystalline size of perovskite via the indirect calcination process was ascribed to the suppressing effect of carbon in the grain growth of perovskite. Furthermore, when the in situ created carbon was applied as a template for pore forming, a highly porous perovskite sintering body packing from the nano-sized perovskite oxide was obtained.