Considerable efforts have been made in the past several decades to search the cheap metal-oxides electrocatalysts  with superior electrical properties including ionic and electronic for electrochemical energy devices. In this work,  simple orthorhombic structured CaFe2O4 nano-particles were embedded on a porous Ni-foam by spin coating  method for the application of air electrode for protonic ceramic fuel cells (PCFCs), which provides high oxygen  reduction activity than using traditional processes. CaFe2O4 coated Ni-foam cathode shows very small areaspecific-resistance (ASR) of ≤0.2 Ω cm2and fuel cell device assembled by CaFe2O4 coated Ni-foam cathode  over ceramic BaZr0.8Y0.2O3 (BZY) electrolyte exhibited a peak power density (PPD) of 612 mW cm− 2 when  operating at 500◦C. The porous Ni-foam support superficially improves the electrical and gas diffusion capabilities along with ionic transport properties of CaFe2O4 by narrowing the bandgap to effectively facilitating  small polaron hopping energy of valence electrons. However, various spectroscopic measurements such as  electrochemical impedance, X-ray photoelectron, thermogravimetric analysis, and Density Functional Theory  (DFT) calculations were employed to understand the improved ORR electrocatalyst function of CaFe2O4 with Nifoam support as three-dimensional heterostructure composite cathode. The results can further help to develop  functional cobalt-free electro-catalysts for low temperature-PCFCs and other related applications.