关键词: 材料加工工艺, 固态电解质, 快速热压烧结, 离子电导率, 掺杂

Abstract:

In this paper， fast hot-pressing sintering process assisted by an electric field was employed to fabricate Ni-doped 3 mol% yttria-stabilized zirconia（3YSZ） solid-state electrolytes. The effects of Ni doping content ranging from 3% to 8% on the phase composition， microstructure， densification， and ionic conductivity of the sintered products were investigated. The research findings indicate that when the Ni doping content is 5%， under process parameters of constant pressure at 20 MPa， heating rate 60 ℃/min to 1 200 ℃， hold for 10 min， the Ni/3YSZ grains are tightly packed with a relative density of up to 98%. At a test temperature of 300 ℃， the ionic conductivity reaches 6.24 μS/cm. By utilizing the multiphysics coupling software COMSOL， a three-dimensional multi-channel cross-flow steady-state single cell model was established， taking the multi-channel planar anode-supported solid oxide fuel cell（SOFC） as the research subject. The electrical conductivity of the prepared 3YSZ/Ni solid-state electrolytes with different Ni contents was evaluated， and the power density achieved could reach 22 W/m2. This provides a new approach to enhancing the low-temperature performance of SOFC electrolytes.

Key words: materials processing technology, solid-state electrolyte, fast hot-pressing sintering, ionic conductivity, doping