Synergetic effect of spontaneous Fe diffusion for enabling immediately switchable operations in NiFe-supported solid oxide cells

Abstract

Solid oxide cells (SOCs) are highly efficient energy conversion systems, offering switchable capabilities for power and fuel production. NiFe metal-supported structures in SOCs show promising advantages in structural stability and scalability. This study explores the synergistic effect of spontaneous Fe diffusion in NiFe-supported SOCs, enhancing alloy catalyst formation in the electrode and improving the sinterability of the zirconia-based electrolyte. This results in increased activity for carbon fuel reactions, resistance to coking, and a remarkably low ohmic resistance of 0.06 Ω cm2 at 800 °C. The NiFe support also enhances structural stability, enabling reversible and multifuel operation. The single cell achieves exceptional maximum power densities of 2.6 and 2.0 W cm−2 in fuel cell mode (3 % H2O/H2 and dry CO) and current densities of − 1.51 and − 1.38 A cm−2 in electrolysis cell mode (1.3 V, 20 % H2O/H2 and 20 % CO2/CO) at 800 °C, respectively.