کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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1463213 | 989644 | 2011 | 6 صفحه PDF | دانلود رایگان |

In the present study, ceria powder with and without gadolinium (Gd) or zirconium (Zr) dopants were synthesized by a spray pyrolysis (SP) process. The resulting powders (undoped CeO2, Gd-doped ceria and Zr-doped ceria) were first mixed with organic binders, screen printed on alumina substrates, and then heat treated at 1200 °C for 2 h in air. Experimental results showed that the as-pyrolyzed powders were nanocrystalline and spherical in shape with uneven surfaces. After heat treatment, the powder coatings showed a 3-D network structure with interconnected pores exhibiting a high surface area. The electrical conductivity of CeO2 was increased by the dope of Zr. The increasing rate of conductivity of ZDC (Zr-doped ceria) with decreasing oxygen pressure was also higher than that of undoped CeO2. The CeO2 and ZDC exhibited an n-type semiconductance in all the oxygen pressure regions, showing promise as candidates for sensor applications. The GDC (Gd-doped ceria) revealed a p-type and an n-type semiconductance in high- and low-oxygen pressure regions, respectively. The sensor applications of GDC are thus limited. Meanwhile, the ZDC exhibited a shorter response time due to its smaller grain size, showing a better oxygen sensing behavior.
Journal: Ceramics International - Volume 37, Issue 7, September 2011, Pages 2353–2358