金红石二氧化钛介电常数的光致增大效应

Photoinduced Enhancement of Dielectric Constant in Rutile TiO_2

研究了紫外光照对金红石二氧化钛(TiO_2)和锐钛矿TiO_2介电性质的影响。利用阻抗分析仪,测量暗态和紫外光照下金红石TiO_2和锐钛矿TiO_2在40~106Hz的介电常数。测量结果表明:在50~400Hz,紫外光照可提高金红石TiO_2的介电常数约18%,降低介电损耗约7%。在相同光照和测量频率条件下,锐钛矿TiO_2的介电常数降低约10%。

The effects of ultra violet( UV) light irradiation on the dielectric properties of rutile TiO_2 and anatase TiO_2 were investigated. In the dark and under UV light irradiation,the dielectric constants of rutile TiO_2 and anatase TiO_2 were measured at the frequencies of 40 ~ 106 Hz by impedance spectroscopy. The measurement results show that in the frequency range of 50 ~ 400 Hz,the dielectric constant of rutile TiO_2 is enhanced by18% while the dielectric loss is reduced by 7% by UV light irradiation. The dielectric constant of anatase TiO_2 is reduced by 10% at the same conditions of irradiation and frequency.