Details

Autor(en) / Beteiligte

• Liang, Jun-Ge
• Wang, Cong
• Yao, Zhao
• Liu, Ming-Qing
• Kim, Hong-Ki
• Oh, Jong-Min
• Kim, Nam-Young

Titel

Preparation of Ultrasensitive Humidity-Sensing Films by Aerosol Deposition

Ist Teil von

• ACS applied materials & interfaces, 2018-01, Vol.10 (1), p.851-863

Ort / Verlag

United States: American Chemical Society

Erscheinungsjahr

2018

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Aerosol deposition (AD) is a novel ceramic film preparation technique exhibiting the advantages of room-temperature operation and highly efficient film growth. Despite these advantages, AD has not been used for preparing humidity-sensing films. Herein, room-temperature AD was utilized to deposit BaTiO3 films on a glass substrate with a Pt interdigital capacitor, and their humidity-sensing performances were evaluated in detail, with further optimization performed by postannealing at temperatures of 100, 200, ..., 600 °C. Sensor responses (i.e., capacitance variations) were measured in a humidity chamber for relative humidities (RHs) of 20–90%, with the best sensitivity (461.02) and a balanced performance at both low and high RHs observed for the chip annealed at 500 °C. In addition, its response and recovery were extremely fast, respectively, at 3 and 6 s and it kept a stable recording with the maximum error rate of 0.1% over a 120 h aging test. Compared with other BaTiO3-based humidity sensors, the above chip required less thermal energy for its preparation but featured a more than 2-fold higher sensitivity and a superior detection balance at RHs of 20–90%. Cross-sectional transmission electron microscopy imaging revealed that the prepared film featured a transitional variable-density structure, with moisture absorption and desorption being promoted by a specific capillary structure. Finally, a bilayer physical model was developed to explain the mechanism of enhanced humidity sensitivity by the prepared BaTiO3 film.