Electrical, flexible and humidity-sensing properties of diamine-functionalized graphene oxide film

• Main Authors: Lu, Zhong-Mao, 盧忠懋
• Other Authors: Su, Pi-Guey
• Format: Others
• Language: zh-TW
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/92641300775397575998

碩士 === 中國文化大學 === 化學系應用化學碩士班 === 103 === Novel impedance-type humidity sensors were made using diamines-functionalized graphene oxide (GO) films coated on alumina or plastic substrates. Ethylenediamine (EA) and 1,6-hexanediamine (HA) were used to functionalize GO using N-(3-dimethylaminopropyl)-N-ethylcarbodiimide hydrochloride (EDC) and N-hydroxysuccinimide (NHS) (EDC/NHS) as the coupling reagent. The effect of the chain lengths of diamine on the electrical and humidity-sensing properties　of the diamine-functionalized GO film was investigated. The diamine-functionalized GO film was characterized by atomic force microscopy (AFM) and Fourier transform infrared spectroscopy (FTIR). The impedance-type humidity sensor that was made of EA-GO film exhibited a wide range of working humidities, a high sensitivity, an acceptable linearity, a small hysteresis, high flexibility, a short response/recovery time, a weak dependence on temperature and high long-term stability. The humidity sensor’s linearity depended on the applied frequency. Complex impedance plots and activation energy were applied to elucidate how the ions (H3O+) dominate the conductance of the diamine-functionalized GO film.