The unique characteristics of nanofibers in rational electrode design enable effective utilization and maximizing material properties for achieving highly efficient and sustainable CO₂ reduction reactions (CO₂RRs) in solid oxide electrolysis cells (SOECs). However, practical application of nanofiber-based electrodes faces challenges in establishing sufficient interfacial contact and adhesion with the dense electrolyte. To tackle this challenge, a novel hybrid nanofiber electrode, La_0.6Sr_0.4Co_0.15Fe_0.8Pd_0.05O_3-δ (H-LSCFP), is developed by strategically incorporating low aspect ratio crushed LSCFP nanofibers into the excess porous interspace of a high aspect ratio LSCFP nanofiber framework synthesized via electrospinning technique. After consecutive treatment in 100% H₂ and CO₂ at 700 °C, LSCFP nanofibers form a perovskite phase with in situ exsolved Co metal nanocatalysts and a high concentration of oxygen species on the surface, enhancing CO₂ adsorption. The SOEC with the H-LSCFP electrode yielded an outstanding current density of 2.2 A cm^-2 in CO₂ at 800 °C and 1.5 V, setting a new benchmark among reported nanofiber-based electrodes. Digital twinning of the H-LSCFP reveals improved contact adhesion and increased reaction sites for CO₂RR. The present work demonstrates a highly catalytically active and robust nanofiber-based fuel electrode with a hybrid structure, paving the way for further advancements and nanofiber applications in CO₂-SOECs.

An universal oxygen-electrode, compatible to both oxygen- and proton-conducting solid oxide electrochemical cells (O-SOCs and H-SOCs, respectively), as well as for electricity and hydrogen production purpose is showcased.