HU Jiaxing, LUO Linghong, CHENG Liang, XU Xu, WU Yefan
(Jingdezhen Ceramic Institute, Key Laboratory of Fuel Cell Macrials and Devices Jiangxi Province, Jingdezhen 333403, Jiangxi, China)
Abstract: The sintering behavior and electrochemical performances of Gd0.1Ce0.9O1.95 powders with two different kinds of particle size distribution produced in Shenzhen City and Ningbo Sofucman Energy Technology Limited Company respectively were studied in this paper. The sintering characteristics of 10GDC powders precalcined at different temperatures were evaluated, and the best precalcination temperature was determined. The water absorption and bulk density of 10GDC electrolytes sintered at 1500 ℃, 1550 ℃ and 1600 ℃ were tested. The crystal phase of 10GDC powders was determined by XRD and the densification of the sintered bodies was observed via SEM.The results show that the 10GDC powder from Shenzhen precalcined at 1000°C can be sintered at 1500°C completely and its relative density is 98.06%. The SOFCMAN 10GDC powder can be sintered at 1600°C completely and its relative density reaches 96.91%. The Shenzhen 10GDC powder, with its activity higher than that of the SOFCMAN 10GDC powder, can obtain the dense sintered body at a relatively lower temperature. The conductivities and activation energies of these two kinds of 10GDC electrolytes were measured by AC impedance spectroscopy at 450-750 ℃. The results show that the apparent activation energies of total conductance of Shenzhen 10GDC electrolyte sintered at 1500 ℃ and SOFCMAN 10GDC electrolyte sintered at 1600°C were 1.42 eV and 1.28 eV respectively. The electrolyte conductivity of SOFCMAN 10GDC is higher than that of Shenzhen 10GDC at 550 ℃ -750 ℃ It can be seen that SOFCMAN 10GDC powder has higher electrical properties and its sintered body’s ion conductivity is higher.
Key words: 10GDC electrolyte; particle size; sintering; electrical conductivity