Abstract: CeO2 nanocrystalline with different morphologies (nanobelts and nanoparticles) were synthesized via hydrothermal and sol-gel methods with Ce(NO3)3·6H2O as precursor.The phase structures and morphologies of products were investigated by XRD, SEM and TEM.The performance of humidity sensors fabricated by both samples were evaluated in detail.Qualitative analyses indicate that the morphologies of products has a significant effect on the properties of sensor.The sensor fabricated by nanobelts shows higher sensitivity, fast response (7 s) and rapid recovery (7 s) charateristics(15;-95;RH), and the maximum humidity hysteresis is 4; in the test humidity range compared with nanoparticles sample.The excellent performance of nanobelts sample can be attributed to the large specific surface area.

Key words: CeO2 nanocrystalline with different morphologies (nanobelts and nanoparticles) were synthesized via hydrothermal and sol-gel methods with Ce(NO3)3·6H2O as precursor.The phase structures and morphologies of products were investigated by XRD, SEM and TEM.The performance of humidity sensors fabricated by both samples were evaluated in detail.Qualitative analyses indicate that the morphologies of products has a significant effect on the properties of sensor.The sensor fabricated by nanobelts shows higher sensitivity, fast response (7 s) and rapid recovery (7 s) charateristics(15;-95;RH), and the maximum humidity hysteresis is 4; in the test humidity range compared with nanoparticles sample.The excellent performance of nanobelts sample can be attributed to the large specific surface area.