Ryu Sangbong, Choi In Won, Kim Yang Jae, Lee Sanghoon, Jeong Wonyeop, Yu Wonjong, Cho Gu Young, Cha Suk Won
Center for Energy Research, University of California San Diego, 9500 Gilman Drive, La Jolla, California 92093, United States.
Department of Mechanical Engineering/SNU-IAMD, Seoul National University, 1, Gwanak-ro, Gwanak-gu, Seoul 08826, Republic of Korea.
ACS Appl Mater Interfaces. 2023 Sep 13;15(36):42659-42666. doi: 10.1021/acsami.3c09025. Epub 2023 Sep 4.
To overcome significantly sluggish oxygen-ion conduction in the electrolytes of low-temperature solid-oxide fuel cells (SOFCs), numerous researchers have devoted considerable effort to fabricating the electrolytes as thin as possible. However, thickness is not the only factor that affects the electrolyte performance; roughness, grain size, and internal film stress also play a role. In this study, yttria-stabilized zirconia (YSZ) was deposited via a reactive sputtering process to fabricate high-performance thin-film electrolytes. Various sputtering chamber pressures (5, 10, and 15 mTorr) were investigated to improve the electrolytes. As a result, high surface area, large grain size, and residual tensile stress were successfully obtained by increasing the sputtering pressure. To clarify the correlation between the microstructure and electrolyte performance, a YSZ thin-film electrolyte was applied to anodized aluminum oxide-supported SOFCs composed of conventional electrode materials which are Ni and Pt as the anode and the cathode, respectively. The thin-film SOFC with YSZ deposited at 15 mTorr exhibited the lowest ohmic resistance and, consequently, the highest maximum power density (493 mW/cm) at 500 °C whose performance is more than five times higher than that of the cell with YSZ deposited at 5 mTorr (94.1 mW/cm). Despite the basic electrode materials, exceptionally high performance at low operating temperature was achieved via controlling the single fabrication condition for the electrolyte.
为了显著克服低温固体氧化物燃料电池（SOFC）电解质中缓慢的氧离子传导问题，众多研究人员付出了巨大努力来制造尽可能薄的电解质。然而，厚度并非影响电解质性能的唯一因素；粗糙度、晶粒尺寸和内部薄膜应力也起着作用。在本研究中，通过反应溅射工艺沉积氧化钇稳定的氧化锆（YSZ）来制造高性能薄膜电解质。研究了各种溅射室压力（5、10和15毫托）以改进电解质。结果，通过提高溅射压力成功获得了高表面积、大晶粒尺寸和残余拉应力。为了阐明微观结构与电解质性能之间的相关性，将YSZ薄膜电解质应用于由传统电极材料组成的阳极氧化铝支撑的SOFC，其中阳极和阴极分别为Ni和Pt。在15毫托下沉积YSZ的薄膜SOFC在500°C时表现出最低的欧姆电阻，因此具有最高的最大功率密度（493毫瓦/平方厘米），其性能比在5毫托下沉积YSZ的电池（94.1毫瓦/平方厘米）高出五倍以上。尽管电极材料基本相同，但通过控制电解质的单一制造条件，在低工作温度下实现了异常高的性能。
