Jihwan An

Employing porous structures is essential in high‐performance electrochemical energy devices. However, obtaining uniform functional coatings on high‐tortuosity structures can be challenging, even with specialized processes such as atomic layer deposition (ALD). Herein, a novel method for achieving a porous composite electrode for solid oxide fuel cells by coating La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3 − δ (LSCF) powders with ZrO 2 using a powder ALD process is presented. Unlike conventional ALD, powder ALD can be used to fabricate extremely uniform coatings on porous electrodes with a thickness of tens of micrometers. The powder ALD ZrO 2 coating is found to effectively suppress chemical degradation of the LSCF electrodes. The cell with the powder ALD coated cathode shows a 2.2 times higher maximum power density and 60% lower thermal degradation in activation resistance than the bare LSCF cathode cell at 700–750 °C. The result demonstrated in this study is expected to have significant implications for high‐performance and durable electrodes in energy conversion/storage devices.