Enhanced ionic conductivity in phase stabilized yttria-doped zirconia nanowires

Yttria-doped zirconia (YSZ) is a remarkable functional material with wide applications, including solid oxide fuel cells (SOFCs) and oxygen sensors, due to its excellent mechanical and electrical properties. However, the elevated operating temperatures using the conventional YSZ electrolytes for the solid ionic devices yield high cost and limited lifetime. Here we report YSZ nanowires with doping content rang of 0-10 mol% prepared by electrospinning. The variety of tetragonal and cubic phases in the nanowires has been detected, which demonstrates that in comparison to bulk counterparts, the high-temperature phases in zirconia-based nanowires could be stabilized at lower doping levels, owing to the critical crystallite size effect. The electrical conductivity of uniaxially aligned nanowires with respect to yttria content has been investigated. The highest ionic conductivity of 0.01 Scm− 1 is achieved at a low temperature of 375 °C for the YSZ nanowires with 6.5 mol% yttria, which is 290 times enhancement over corresponding bulk.