High-Performance (Cu,Mn)<sub>3</sub>O<sub>4</sub>/CuO Network for Oxygen Electrode Contact Layers in Solid Oxide Cells via Electrodeposition and In Situ Sintering.

Abstract

Solid oxide cells (SOCs) are efficient energy conversion devices that facilitate flexible utilization between electricity and chemical energy. However, current collection efficiency between cells and interconnects remains a key challenge for the large-scale application of SOCs. This study reports on a (Cu,Mn)₃O₄/CuO mesh, designed as the oxygen electrode contact layer (CL) for SOCs, prepared through a straightforward manganese electrodeposition on copper mesh and in situ reactive sintering method. The conformal and continuous spinel layer significantly reduces the electron conduction resistance of the composite mesh, showing an area-specific resistance (ASR) value of 19 mΩ cm² at 850 °C, approximately half that of the pristine copper mesh. In midterm testing, including 300 h of isothermal aging at 850 °C and 20 thermal cycling events between 200 °C and 850 °C, the ASR of a sandwich structure including oxygen electrode/CL/interconnect remains below 30 mΩ cm². Besides, a larger composite mesh with 16 cm² active area is evaluated in a single-cell test at 850 °C, and the total Ohmic resistances for the fuel cell and electrolysis cell are 480 mΩ cm² and 561 mΩ cm², respectively. The present work offers new insights into the design of 3D and self-supporting CLs for SOCs.