Due to the relative low activation energy, protonic ceramic fuel cells (PCFCs) have attracted increasing attention in recent years because of the efficient low-temperature (LT, 300-600^oC) operation. However, the insufficient LT activity of cathode materials for oxygen reduction reaction (ORR) is still one of the significant challenges to achieve excellent performance. It has been recognized that the triple conductivity (electron, oxygen ion, and proton) are prerequisite properties for a high-performance PCFC cathode. Many strategies on material selection have already been done to meet this requirement. BaCo_0.4Fe_0.4Zr_0.1Y_0.1O_3-δ (BCFZY0.1) was reported as a single-phase triple conducting oxide cathode material which provides improvement of cell performance. However, the pure phase in return limits the further adjustment of the triple conductivities. The composite structures comprised proton conducting oxide and mixed ionic and electronic conducting can also introduce triple conductivity for cathode materials. Unfortunately, traditional fabrication methods for these composites are limited by mechanical mixing with two or more components, which significantly restricted contact sites/areas of different components and further obstacle ORR performance. Thus, the nanocomposite cathodes are demanded with high phase connection and flexible phase adjustment. Herein, the modified Pechini method was utilized to synthesize nanocomposite materials comprised of a mixed ionic and electronic conducting cubic perovskite phase and a protonic conducting orthorhombic perovskite phase from a nominal composition of BaCe_0.4Fe_0.4Co_0.2O_3-δ (BCFC). This one-pot method not only increased the density of the activated sites/areas for ORR by decreasing grain sizes for each phase but also provided excellent thermodynamic stability because the solid-state reaction thermodynamic equilibrium has arrived during synthesis. BCFC was confirmed to be a new promising nanocomposite cathode material for LT-PCFCs.