Photochemically-Activated p-Type CuGaO<sub>2</sub> Thin Films for Highly-Stable Room-Temperature Gas Sensors
Pei-Te Lin, Chih-Ying Yu, Sin-Huei Ho, Shiuan-Wei Pan, Jyun-Siang Jhang, Yi-Xun Zhang, Yo-Lun Zhang, Tian-Tsz Hsieh, Hao‐Chien Wang, Wen–Jeng Hsueh, Chun‐Ying Huang
Abstract
The photochemical activation process is a promising way to operate metal oxide gas sensors at room temperature. However, this technique is only used in n-type semiconductors. In this study, we report a highly stable p-type copper gallium oxide (CuGaO 2 ) gas sensor fabricated through the facile sol-gel process. The sensor is capable of detecting O 3 gas at room temperature, and its gas response can be further enhanced by ultraviolet (UV) activation. The highest gas response of 7.12 to 5 ppm O 3 gas at a UV intensity of 10 mW cm −2 is achieved at room-temperature. In addition, the CuGaO 2 sensor shows excellent long-term stability, with a degradation of approximately 3% over 90 days. These results strongly support the solution-processed CuGaO 2 as a good candidate for room-temperature gas sensors.