Enhanced NH3 sensing performance of polyaniline via a facile morphology modification strategy

• Published in: Sensors and actuators. B, Chemical Vol. 369; p. 132302
• Main Authors: Duan, Xiaohui, Duan, Zaihua, Zhang, Yajie, Liu, Bohao, Li, Xian, Zhao, Qiuni, Yuan, Zhen, Jiang, Yadong, Tai, Huiling
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 15.10.2022; Elsevier Science Ltd
• Subjects: Ammonia; Composite materials; Gas sensors; Halloysite nanotubes; Morphology; Morphology modification; NH3 sensor; Polyaniline; Polyanilines; Relative humidity; Selectivity; Sensors; Specific surface; Surface area; NH3 sensor; Morphology modification; Halloysite nanotubes; Polyaniline
• ISSN: 0925-4005; 1873-3077
• DOI: 10.1016/j.snb.2022.132302

The synthesis of polyaniline (PANI) composites is an effective method to improve the ammonia (NH3) gas sensing performance of PANI, and it is of great significance to develop a simple method to prepare PANI composites. Herein, the PANI/halloysite nanotubes (PANI/HNTs) composite was prepared via a simple in-situ polymerization method. Morphology characterization results show that the HNTs are covered by PANI to form a porous three-dimensional structure. Especially, the specific surface areas of the PANI and PANI/HNTs are 15.892 and 25.899 m2/g, respectively, and the specific surface area of PANI has been greatly improved (1.63 times). Gas sensing properties test results show that the PANI/HNTs sensor exhibits larger response (1.60 times) and shorter response/recovery times (0.93/0.6 times) than that of the PANI sensor to 10 ppm NH3 (25 °C, 50% relative humidity). In addition, the PANI/HNTs sensor exhibits low detection limit of 10 ppb NH3 and excellent selectivity. The enhanced NH3 sensing performance of PANI can be attributed to the unique hollow structure and large specific surface area of HNTs. In this work, a simple method is proposed to improve the NH3 sensing performance of PANI only by morphology modification. Meanwhile, it provides an idea for the application of HNTs in the field of gas sensors. •The NH3 sensing performance of PANI is improved by a facile morphology modification strategy.•PANI/HNTs sensor was prepared by the in-situ polymerization method.•PANI/HNTs sensor exhibits higher NH3 sensing response than the PANI sensor.•PANI/HNTs sensor has an ultra-low detection limit of 10 ppb NH3.